--- title: "OBD2 Diagnostic Trouble Codes List" slug: obd2-code-list collection: pages date: 2024-04-30T23:07:32 modified: 2026-01-07T23:18:31 url: https://fixmycar.pk/obd2-code-list/ --- ## OBD2 Codes: Diagnostic Trouble Codes List [P2583-4A – Millimeter Wave Radar Function Error](#collapse-e52b2bb69f9fd6bea75e) **DTC code P2583-4A – Millimeter Wave Radar Function Error** indicates a malfunction in the vehicle’s millimeter wave radar system, which plays a crucial role in advanced driver assistance features such as adaptive cruise control and collision mitigation braking. This code typically means the radar sensor is experiencing issues such as misalignment, obstruction, electrical faults, or internal hardware failure. Environmental factors like dirt, ice, or heavy rain can also trigger this error by interfering with radar signal accuracy. When DTC P2583-4A is present, the vehicle’s safety systems may be partially or fully disabled, increasing the risk of accidents. Prompt inspection and recalibration by a certified technician using Honda-specific diagnostic tools is essential to restore full system functionality. If your Honda Vezel Hybrid displays this code, it’s important to address it immediately to ensure optimal performance and safety of your vehicle’s radar-based features.![Honda ADAS Calibration](/uploads/2025/09/IMG-20250924-WA0013.jpg) [vcfront\_a402 Tesla: Electrical System Backup Power is Unavailable](#collapse-986aa5569f9fd6bea75e) The diagnostic trouble code **VCFRONT\_a402** means the Tesla’s **backup power support for the low-voltage electrical system is unavailable**. In normal operation, the high-voltage battery supplies power to the 12V system through a DC-DC converter, and a backup power pathway ensures continued operation of safety-critical components if the main supply is interrupted. When this code is triggered, it indicates that the backup system cannot provide support, leaving the vehicle more vulnerable to electrical interruptions. Symptoms may include warning messages on the screen, possible loss of redundancy in powering safety systems, and an increased risk that the vehicle could shut down unexpectedly if the primary 12V supply fails. The most common causes are a **faulty or degraded 12V battery**, issues with the DC-DC converter, or a problem in the wiring or control module that manages the backup circuit. Tesla recommends immediate service if this code appears, since the absence of backup power can compromise system reliability and potentially affect drivability. [vcfront\_a192 Tesla: Electrical System is Unable to Support all Features.](#collapse-66233ec69f9fd6bea75e) The Tesla diagnostic trouble code **VCFRONT\_a192** indicates that the vehicle’s **electrical system is unable to support all features** because the low-voltage (12V) system is not being maintained properly. The 12V battery supplies power to essential components such as lighting, locks, infotainment, and safety systems. When this alert appears, the car’s controller begins “load shedding,” meaning it disables or limits non-critical systems to preserve power for critical functions. In most cases, this warning signals a failing or depleted 12V battery, or an issue with the DC-DC converter that charges the 12V battery from the high-voltage pack. Drivers may notice symptoms such as warning messages on the touchscreen, reduced functionality of accessories, dimming interior/exterior lights, or difficulty powering on the vehicle. Common causes include a **weak or aging 12V battery**, improper charging from the main battery pack, or excessive electrical load draining the 12V system. If this code appears, Tesla recommends inspecting and typically replacing the 12V battery. If the alert persists after replacement, further diagnosis of the DC-DC converter or related wiring is required. [vcfront\_a182 Tesla: Replace Low-Voltage Lead-Acid (12V) Battery](#collapse-c57cd9869f9fd6bea75e) To **replace the low-voltage lead-acid (12V) battery** in a Model 3 for North American vehicles that still use the AtlasBX/Hankook 85B24LS (12 V, 45 Ah) battery. First confirm whether your car uses a lead-acid or lithium-ion battery, since later Model 3 builds transitioned to lithium-ion. Emphasizes safety, including wearing protective gear, avoiding removal of rear seats except as instructed, and noting that battery failure caused by neglect may not be covered under warranty. The replacement steps differ slightly depending on production date: **vehicles built before October 2020 (no heat pump)** versus **after October 2020 (with heat pump)**. Both procedures involve prepping the car (open frunk, power off, disconnect charger, remove covers), disconnecting the negative and positive terminals (positive first responder loop added on later builds), unplugging the vent tube, removing the hold-down bracket, and carefully lifting out the ~25 lb battery. Installation is the reverse order: place the new battery, secure the bracket (torqued to 6 Nm), reconnect the positive then negative terminals, reattach the vent tube, reinstall covers, and confirm the touchscreen powers up with no 12V warnings. [C1805 – Electronic Park Brake (EPB) Switch Blocked Timeout (MG HS)](#collapse-922785769f9fd6bea75e) The **C1805 fault code** indicates a timeout error in the **Electronic Park Brake (EPB)** switch system, meaning the EPB switch is either physically stuck or electrically unresponsive for too long. This affects the proper engagement or release of the parking brake, potentially compromising vehicle safety. **Causes of C1805 Code** - Stuck or damaged EPB switch - Faulty EPB control unit or wiring issue - Moisture or debris interfering with switch operation ** Symptoms of C1805 Code** - EPB warning light illuminated on the dashboard - Inability to engage or release the electronic parking brake - Audible clicking without brake action when pressing the EPB switch [C100B – Engine Torque Request Not Adjustable (MG HS)](#collapse-45e054f69f9fd6bea75e) The **C100B trouble code** indicates that the Engine Control Module (ECM) is unable to adjust the engine torque request as expected. This signal is essential for proper coordination between the engine and other systems like traction control and transmission. When this code appears, it usually points to a communication fault or control logic issue. **Causes of C100B Code** - Faulty or unresponsive Engine Control Module (ECM) - Communication error between ECM and Transmission Control Module (TCM) - Software glitch or corrupted calibration data **Symptoms of C100B Code** - Reduced engine performance or torque limitation - Traction control or stability system warning lights - Hesitation during acceleration or gear shifting [U0401-68 – Incorrect Start Control Functional Fault in the City-Brake Active System](#collapse-8737a4869f9fd6bea75e) The **DTC code U0401-68 – Incorrect Start Control Functional Fault in the City-Brake Active System** indicates that the vehicle’s control module has received invalid or corrupted data from the Engine Control Module (ECM), specifically affecting the proper operation of the City-Brake Active System. This advanced safety feature, designed to prevent low-speed collisions by automatically applying the brakes, relies on accurate communication between multiple vehicle systems. When this fault code occurs, it may compromise the effectiveness of the City-Brake Active System, leading to reduced safety performance. Common causes include faulty wiring, sensor malfunctions, software issues, or module communication errors. [P0AA6 – High Voltage Circuit Isolation Problem](#collapse-4961a7369f9fd6bea75e) The Honda Vezel **DTC code P0AA6 – High Voltage Circuit Isolation Problem** is a critical diagnostic trouble code that indicates a leakage or insulation fault within the hybrid high-voltage system. This issue typically arises when the vehicle’s onboard diagnostic system detects a loss of electrical isolation between the high-voltage battery, inverter, or associated wiring and the chassis ground. A P0AA6 code can be caused by moisture intrusion, damaged insulation, corroded connectors, or a failing battery pack, and it poses a serious safety risk if not addressed promptly. When this code appears, the hybrid system may shut down to prevent potential electric shock or further damage. Immediate inspection by a certified technician with hybrid system expertise is recommended. If you own a Honda Vezel and encounter DTC P0AA6, swift diagnosis and repair are essential to ensure safe operation and optimal vehicle performance. [Honda 83-11 PCM Malfunction (Engine)](#collapse-d823ea369f9fd6bea75e) The Honda Vezel **DTC code P0AA6 – High Voltage Circuit Isolation Problem** is a critical diagnostic trouble code that indicates a leakage or insulation fault within the hybrid high-voltage system. This issue typically arises when the vehicle’s onboard diagnostic system detects a loss of electrical isolation between the high-voltage battery, inverter, or associated wiring and the chassis ground. A P0AA6 code can be caused by moisture intrusion, damaged insulation, corroded connectors, or a failing battery pack, and it poses a serious safety risk if not addressed promptly. When this code appears, the hybrid system may shut down to prevent potential electric shock or further damage. Immediate inspection by a certified technician with hybrid system expertise is recommended. If you own a Honda Vezel and encounter DTC P0AA6, swift diagnosis and repair are essential to ensure safe operation and optimal vehicle performance. [P317A-97 Motor System](#collapse-704797c69f9fd6bea75e) P317A-97 refers to a malfunction within the motor system of the hybrid or electric vehicle (EV), specifically indicating a performance or component-related issue in the hybrid powertrain. This fault code is triggered when the system detects irregularities in the electric motor's operation, such as abnormal speed, torque output, or internal sensor feedback. The motor is a crucial part of the hybrid system, providing propulsion and regenerative braking functions. Potential causes of this DTC include issues with the motor itself, inverter malfunction, sensor failure (such as rotor position or temperature sensors), or wiring/connectivity faults. Symptoms may include reduced power, warning lights on the dash (such as EV or hybrid system alerts), or the vehicle entering limp mode. [P3130-86 Inverter Discharge Error](#collapse-401acb469f9fd6bea75e) P3130-86  indicates an "Inverter Discharge Error," typically found in hybrid or electric models. This code is triggered when the inverter fails to properly discharge high-voltage electricity during system shutdown or fault conditions. The inverter plays a key role in managing the flow of electrical energy between the high-voltage battery and the electric motor. Proper discharge is essential to ensure safety and protect internal components from electrical damage. Causes of this error may include a faulty inverter, malfunctioning discharge circuit, damaged relays, or wiring issues within the high-voltage system. Symptoms may involve warning lights, reduced performance, or the vehicle entering a fail-safe mode. [P3176-86 Inverter Condenser](#collapse-d232d2969f9fd6bea75e) P3176-86 refers to a fault in the inverter condenser system, which is a critical component in hybrid and electric vehicles. The inverter condenser is responsible for cooling the inverter, which manages power flow between the battery and the electric motor. This code is triggered when the system detects an abnormal condition such as overheating, low coolant flow, or electrical issues within the inverter cooling system. Potential causes include a faulty inverter cooling pump, low coolant level, air in the cooling lines, or a malfunctioning temperature sensor. Symptoms may include reduced vehicle performance, warning lights on the dashboard, or the vehicle entering fail-safe mode to prevent damage. [P3178-86 ECU Activation Error](#collapse-a7b26ce69f9fd6bea75e) P3178-86 on a Nissan vehicle refers to an "ECU Activation Error," indicating that the Engine Control Unit (ECU) has failed to activate or initialize properly during the vehicle’s startup sequence. This error often occurs in vehicles with Intelligent Key or immobilizer systems, where proper authentication between the key, Body Control Module (BCM), and ECU is required before engine start. The code may be triggered by a mismatch in the immobilizer signal, corrupted ECU programming, faulty key fob, or communication issues between control modules. Symptoms can include a no-start condition, security warning lights, or intermittent starting problems.  [U1000-01 Can Communication Circuit (SONAR)](#collapse-cdcbf9869f9fd6bea75e) U1000-01 code related to specifically to the Parking Distance Control (SONAR) system, indicates a CAN (Controller Area Network) communication error affecting the sonar sensors or control module. This code means that the sonar control unit is either not receiving or not transmitting data properly over the CAN network. The parking distance control system relies on accurate, real-time communication between sensors and the vehicle’s main control modules to detect obstacles and assist with parking. A communication failure may result in the system being disabled or functioning incorrectly, leading to warning messages or loss of parking assist features. Potential causes include damaged wiring, corroded connectors, poor grounding, or a malfunctioning sonar control module. Proper diagnosis involves checking the CAN line continuity, power and ground supply to the sonar unit, and using a diagnostic scan tool to verify module communication. [P0A8D-00 14VOLT Power Voltage](#collapse-188403869f9fd6bea75e) P0A8D-00 indicates a fault related to the "14-Volt Power Voltage" system, which typically refers to the hybrid or electric vehicle's auxiliary power supply. This code is triggered when the vehicle's control module detects an abnormal voltage level either too high or too low on the 14V power line that supplies essential components such as the DC-DC converter, electronic control units, and auxiliary systems. The issue may stem from a faulty DC-DC converter, poor ground connection, damaged wiring, or a malfunctioning battery or alternator system (in non-hybrid models). Symptoms can include warning lights, malfunctioning electronics, or inconsistent charging. Accurate diagnosis involves checking voltage levels, testing the converter and battery, and inspecting electrical connectors for corrosion or damage. Prompt attention is crucial to maintain system reliability and prevent further electrical issues. [B2788-19 Compressor Overcurrent (HVAC Code)](#collapse-7b68f1569f9fd6bea75e) B2788-19 on a Nissan vehicle refers to a "Compressor Overcurrent" condition in the air conditioning (A/C) system. This fault code is typically triggered when the A/C compressor draws more electrical current than normal, indicating a possible internal fault within the compressor, such as mechanical seizure or short-circuited windings. The overcurrent condition may also be caused by wiring issues, a faulty compressor clutch, or a defective A/C control module. When this code appears, the vehicle's A/C system may shut down or operate intermittently to prevent further damage. [C1143 Nissan Steering Angle Sensor Circuit](#collapse-02b624269f9fd6bea75e) C1143 on a Nissan vehicle refers to a fault in the Steering Angle Sensor Circuit. This diagnostic trouble code is triggered when the ABS control module detects an abnormal or no signal from the steering angle sensor, which is crucial for stability and traction control systems. The steering angle sensor monitors the position and rotation of the steering wheel and relays this data to the vehicle’s onboard computer to help determine the intended direction of travel. If the circuit is faulty due to wiring issues, sensor failure, or poor connections, it can lead to warning lights on the dashboard, such as the ABS or VDC (Vehicle Dynamic Control) indicators. [P208B Reductant Pump " A" Control Performance/Stuck Off](#collapse-885e0a669f9fd6bea75e) **P208B** indicates that the Reductant Pump "A" is not performing as expected or is stuck in the "off" position. This pump is responsible for delivering Diesel Exhaust Fluid (DEF) to the Selective Catalytic Reduction (SCR) system, which reduces harmful nitrogen oxide (NOx) emissions. Common causes for this code include a faulty DEF pump, electrical issues such as damaged wiring or connectors, contaminated DEF, or a malfunctioning Powertrain Control Module (PCM) . Symptoms may involve the illumination of the check engine light, warnings about DEF system malfunctions, and potential engine performance issues. [P204C Reductant Pressure Sensor Circuit Low](#collapse-1f9bc1769f9fd6bea75e) The OBD-II code **P204C** signifies a low voltage condition in the Reductant Pressure Sensor circuit, a critical component of the Selective Catalytic Reduction (SCR) system in diesel vehicles. This sensor monitors the pressure of Diesel Exhaust Fluid (DEF), ensuring proper injection to reduce harmful nitrogen oxide (NOx) emissions. A low voltage reading can result from issues like a faulty sensor, damaged wiring, or problems within the SCR system. Symptoms may include an illuminated check engine light, reduced engine performance, and increased emissions . Prompt diagnosis and repair are essential to maintain vehicle efficiency and comply with emission standards. [P203C Reductant Level Sensor A Circuit Low](#collapse-b46791369f9fd6bea75e) The OBD-II code P203C indicates a low voltage condition in the Reductant Level Sensor A circuit, which monitors the Diesel Exhaust Fluid (DEF) level in the tank. This issue can lead to improper DEF dosing, resulting in increased emissions and potential engine performance problems. Common causes include a faulty sensor, wiring issues, or contaminated DEF. Symptoms may involve the check engine light illumination, reduced fuel efficiency, and decreased engine power. Timely diagnosis and repair are essential to maintain emission control and engine performance. [C1AB4 and C1AB5 Toyota - Blind Spot Monitor](#collapse-e9dad6e69f9fd6bea75e) This C1AB4 Diagnostic Trouble Code (DTC) is stored when the Blind Spot Monitor Sensor Left (LH) detects an open in the Outer Rear View Mirror Sub-Assembly Left (LH) (Outer Rear View Mirror Indicator Left \[LH\]). C1AB5 Toyota DTC code is stored when the Blind Spot Monitor Sensor Right (RH) detects an open in the Outer Rear View Mirror Sub- Assembly Right (RH) (Outer Rear View Mirror Indicator Right \[RH\]). ![](/uploads/2025/01/C1AB4-Toyota.jpg) [C1614 ECU Malfunction Toyota](#collapse-dcbbb7169f9fd6bea75e) This Diagnostic Trouble Code (DTC) is stored if the Parking Assist ECU judges that there is an internal malfunction as a result of its self-check. The Parking Assist ECU stores different types of information during initialization. If the Parking Assist ECU cannot read the stored information when activated, the Parking Assist ECU judges that there is an internal malfunction and stores this DTC. [B2438 Camera Detection Malfunction](#collapse-ed0553b69f9fd6bea75e) This DTC is output when there is foreign matter on the front glass or the inner rear view mirror assembly (adaptive high beam system sensor), and the forward view is obstructed. [P3107 Toyota Code - Lost communication with airbag system control module](#collapse-cf8bc4069f9fd6bea75e) ## P3107 Toyota Code The Toyota diagnostic trouble code P3107 refers to a communication error between the vehicle’s main Electronic Control Unit (ECU) and the airbag system control module. This particular error indicates a disruption or loss of communication between these essential components responsible for managing and controlling the vehicle’s airbag system. When this code appears, it signifies a potential issue with the wiring, connectors, or modules involved in transmitting data between the ECU and the airbag system control module.  Prompt attention and thorough inspection of the wiring harnesses, connectors, and associated components are crucial to diagnose and rectify the problem, ensuring the proper functioning of the vehicle’s safety systems. Professional assistance or specialized diagnostic tools may be necessary to accurately identify and resolve the underlying cause triggering this communication fault. ![P3107 Toyota Code - Lost communication with airbag system control module​](/uploads/2024/01/P3107-Toyota-Code-Lost-communication-with-airbag-system-control-module​.webp) [C1466 Toyota Code - Rear Speed Sensor Right](#collapse-cec9b3d69f9fd6bea75e) ## C1466 Toyota Code The C1466 code in Toyota vehicles specifically refers to an issue with the rear speed sensor on the right side of the vehicle. This sensor plays a crucial role in measuring the speed of the wheel and ensuring proper functioning of the vehicle’s anti-lock braking system (ABS) and traction control system. When this code is triggered, it indicates a problem with the right rear speed sensor, which could be caused by various factors such as sensor malfunction, damaged wiring, or connectivity issues. It’s essential to address this problem promptly as it can affect the vehicle’s stability control and ABS functionality, potentially compromising safety. Professional diagnostics and inspection of the sensor, wiring, and related components are necessary to pinpoint and rectify the issue, ensuring the vehicle operates optimally and safely on the road. ![C1466 Toyota Rear Speed Sensor Right](/uploads/2024/01/C1466-Toyota-Rear-Speed-Sensor-Right.jpg) [P1544 ERS OFF Switch Circuit Malfunction](#collapse-7bba74a69f9fd6bea75e) ## P1544 Toyota Code The P1544 diagnostic trouble code (DTC) refers to a potential malfunction in the ERS (Electronic Range Select) off switch circuit. This code indicates that there is an issue with the circuit responsible for controlling the ERS off switch in the vehicle. The ERS system allows drivers to manually select and control the gear range in vehicles equipped with automatic transmissions. When the circuit malfunctions, it can lead to the inability to engage or disengage the ERS off mode. This may result in a loss of control over the gear selection and affect the vehicle’s performance. To address the P1544 DTC, it is recommended to have the vehicle inspected by a professional technician who can diagnose the specific cause of the circuit malfunction and repair or replace any faulty components to restore proper functionality of the ERS off switch circuit. [P1602 Toyota Battery Voltage Drop Malfunction When Start](#collapse-e13985b69f9fd6bea75e) ## P1602 Toyota Code The P1602 diagnostic trouble code (DTC) related to a battery voltage drop malfunction during startup indicates a potential issue with the vehicle’s electrical system. When this code is triggered, it suggests that there is a drop in voltage or insufficient power supply to the engine control module (ECM) during the starting process. The ECM relies on a stable and sufficient power source to properly manage various engine functions. If there is a voltage drop during startup, it can lead to erratic engine performance, difficulty in starting the vehicle, or even engine stalling. To address the P1602 DTC, it is recommended to have the vehicle inspected by a qualified technician who can assess the battery, alternator, and wiring connections to identify and rectify any faults in the electrical system. They will ensure that the vehicle receives the required voltage during startup to prevent any malfunctions and ensure proper engine operation. ![P1602 battery voltage drop malfunction when start diagnostic trouble code](/uploads/2023/07/P1602-battery-voltage-drop-malfunction-when-start-diagnostic-trouble-code.jpeg) [P203F Reductant Level Too Low](#collapse-a52963e69f9fd6bea75e) ## P203F Toyota Code This is significant because, in the majority of cases, reductant level sensors are found on diesel-powered vehicles that have a DEF (Diesel Exhaust Fluid) storage tank. One of the main objectives of the ECM, as previously indicated, is to reduce overall vehicle emissions. DEF, a urea solution, is used in diesel engines to help with exhaust burning. The ECM receives information about the level of DEF fluid in its storage tank via the reductant level sensor. ![P203F Reductant Level Too Low](/uploads/2022/11/P203F-Reductant-Level-Too-Low.png) [P2238 Trouble Code: O2 Sensor Positive Current Control Circuit Low](#collapse-92d2e8069f9fd6bea75e) ## P2238 code The engine control module (ECM) detects the O2 sensor for bank 1 with OBD-II generic code P2238. For the heating control circuit of the O2 sensor, sensor number one has a short circuit. Indicating a shorted O2 sensor heater circuit, which results in low circuit voltage control. As a result, the ECM will place the engine into failure mode or open loop fuel control, preventing the fuel feedback control from functioning. Additionally, this will result in the car failing the emissions test. ![p2238 code toyota](/uploads/2022/10/WhatsApp-Image-2022-06-17-at-5.20.34-PM-2.jpeg) [P058A01 Auxiliary Battery Monitor Module General Electric Failure](#collapse-fca469669f9fd6bea75e) ## P058A01 Toyota  The voltage, current, and temperature of the battery are all detected by the battery status sensor assembly. The voltage and current are used to compute the charging condition, which is then sent to the ECM. Based on that signal, the ECM sends an order to the generator assembly to create voltage. The battery temperature is also estimated and sent to the ECM from the change in the resistance value of the thermistor incorporated into the battery status sensor assembly. When the battery is heated, the ECM limits the charging current and safeguards the battery based on this signal. ![P058A01 Auxiliary Battery Monitor Module General Electric Failure](/uploads/2022/04/P058A01-Auxiliary-Battery-Monitor-Module-General-Electric-Failure.png) [P1251 Toyota Hilux Turbocharger Electric Stepper Motor Failure](#collapse-890d0ec69f9fd6bea75e) ## P1251 Toyota Hilux  P1251 is the most prevalent code for Hilux stepper problems. The codes are only a warning that you may have a problem with the Hilux turbocharger electric motor. This code, in the lack of further evidence, implies that the stepper motor has been changed. It’s also unusual for both the turbo and stepper motors to fail at the same time. Low boost with no evident physical signs is most likely due to a stepper motor malfunction. Any trouble codes that the ECU may have thrown should be investigated. ![DTC P1251 Stepper Motor Toyota Hilux Vigo](/uploads/2022/01/DTC-P1251-Stepper-Motor-Toyota-Hilux-Vigo.png) [P0AA6 - Hybrid/EV Battery Voltage System Isolation Lost](#collapse-6fc945769f9fd6bea75e) ## P0AA6 DTC  A high voltage isolation metre is included in the car. The high voltage isolation circuit’s function is to measure the resistance between the high voltage positive and negative direct current (DC) bus and chassis ground. When the ignition switches from ON to OFF and the high voltage contactor relays open, the battery energy control module performs this test. An internal isolation sensor in the battery energy control module detects the resistance between the high voltage DC positive and negative bus and chassis ground. This sensor circuit is subjected to an internal self-check by the battery energy control module. A low amplitude or compressed return signal indicates a lack of chassis ground resistance, and the hybrid powertrain control module 2 will indicate a loss of isolation. ![P0AA6 DTC Honda and Toyota](/uploads/2021/12/P0AA6-DTC-Honda-and-Toyota-e1639815806181.jpg) [P1737 Shift Motor Short to Ground](#collapse-72f98ce69f9fd6bea75e) ## DTC P1737 Shift Motor Short To Ground is the generic description for the P1737 OBD2 code. TCCU sets DTC P1737 if TCCU detects Shift Motor control circuit is open or short to ground. The TCCU receives feedback from the shift motor through the position encoder. Four encoder switch signals offer information on the rotational direction and position of the shift motor. The TCCU supplies 5 volts to the MPS (Motor Position Sensor). The shift motor functions when the mode switch is changed, and the MPS contact point generates an ON/OFF signal. The TCCU checks the operation of the shift motor when it receives 5 volts. ![p1737 shift motor short to ground](/uploads/2021/11/OBD2-Code-P1737.jpg) [P0A3F Motor Rotor Position Sensor Circuit](#collapse-28bd66869f9fd6bea75e) ## DTC P0A3F Based on the inputs from the resolver-type position sensor, the motor control module monitors the angular position, speed, and direction of the drive motor generator rotor. A driving coil, two driven coils, and an irregularly shaped metallic rotor make up the position sensor. The drive motor generator’s shaft is mechanically linked to the metallic rotor. 1. There can be inoperative drive motor generator. 2. There can be opened or shorted drive motor generator harness. 3. Drive motor generator circuit inferior electrical connection. ![P0A3F Motor Rotor Position Sensor](/uploads/2021/10/P0A3F-Motor-Rotor-Positon-Sensor.jpg) [P0139 HO2S S2 Slow Response](#collapse-302f7a869f9fd6bea75e) ### DTC P0139 This is a common Onboard Diagnostic-II code P0139 that indicates a voltage drop below in the O2 Sensor 2 Bank 1 circuit. During the deceleration cutoff point, the voltage should be at least 02 volts for at least seven seconds. Essentially, the ECM (Engine Control Module) in your car is determining that the sensor’s reaction is too sluggish. This will start to set off the fault code, and the dreaded “check engine” light will appear on your dashboard. ### Normal causes for the P0139 Code: 1. It’s possible that your vehicle’s fuel injection system has a leak, resulting in additional fuel being left in the exhaust system. 2. Faulty rear O2 sensor wiring. The wiring could simply be loose or worn. 3. Bad catalytic converter. ![P0139](/uploads/2021/10/P0139.jpg) [C1A11 Front Radar Sensor Incorrect Axial Gap](#collapse-665f8f769f9fd6bea75e) ## DTC C1A11 Toyota The driving support ECU assembly transmits pre-collision system control operation signals based on signals from the millimetre wave radar sensor assembly. The millimetre wave radar sensor assembly performs self diagnostic to see if the sensor beam axis has deviated when the vehicle is assessed to be moving in a straight line or on a gentle curve based on inputs from the yaw rate sensor, etc. The driving support ECU assembly detects and saves DTC C1A11 if the millimetre wave radar sensor assembly beam axis has deviated. ### DTC Detection Condition When the engine switch is on (IG), misalignment of the millimeter wave radar sensor assembly is detected for approximately 0.2 seconds. ![DTC C1A11 Toyota](/uploads/2021/10/DTC-C1A11-Toyota.jpg) [B2477 Rear Height Sensor Failure](#collapse-5e1e54669f9fd6bea75e) ## DTC B2477 Rear suspension stroke sensor circuit malfunction detected. **Cause:** 1. Check for loose or poor connection the front suspension stroke sensor 2. Open/Short in the wire(s) 3. Faulty rear suspension stroke sensor ![](/uploads/2021/10/b2477-Rear-Height-Sensor.jpg) [B2476 Front Height Sensor Failure](#collapse-aedaf6f69f9fd6bea75e) ## P2583-4A – Millimeter Wave Radar Function ErrorDTC B2476 Front suspension stroke sensor circuit malfunction detected. **Cause:** 1. Check for loose or poor connection the front suspension stroke sensor 2. Open/Short in the wire(s) 3. Faulty front suspension stroke sensor ![B2476 Front Height Sensor](/uploads/2021/10/B2476-Front-Height-Sensor.jpg) [P2602 Honda Coolant Pump Control Circuit Low](#collapse-b40f89a69f9fd6bea75e) ## Honda P2602  This general powertrain/engine diagnostic trouble code pertains to all OBDII equipped engines with electric coolant pumps, however it appears more frequently in Ford, Honda, Nissan, and Toyota hybrid vehicles. The Coolant Pump ‘A’ Control Circuit signal is monitored by the Powertrain Control Module (PCM). When the Coolant Pump ‘A’ Control Circuit signal is out of factory specifications, the PCM sets the OBDII code. The Coolant Pump A (CP-A) is commonly located in front of the engine, on top of the engine, inside the wheel wells, or against the bulkhead. The Powertrain Control Module sends an electrical signal to the CP-A, which controls it (PCM). ### The following are some of the symptoms of a P2602 code: 1. Malfunction Indicator Light On 2. Overheating 3. A/C system not functioning properly ![p2602 honda](/uploads/2021/10/p2602-honda.jpg) [P2583-97 Dust or Dirt On Millimeter Wave Radar](#collapse-c90e88a69f9fd6bea75e) ## Honda P2583-97 The Front Distance Range Sensor detects light reflected from a vehicle ahead by irradiating laser forward and calculates a distance from the vehicle ahead as well as a relative speed. The Front Distance Range Sensor transmits the presence/absence of the vehicle ahead as well as the distance from the vehicle to the vehicle Cruise Control Unit based on the detected signal. The Cruise Control Unit requests the Engine Control Module (ECM) to set the OBDII code P2583-97 when the vehicle’s Cruise Control Unit loses connection with the Front Distance Range Sensor. ![Millimeter Radar Testing](/uploads/2021/08/WhatsApp-Image-2021-08-12-at-11.17.12-AM-2.jpeg) [C2318 - Low Voltage Error Power Supply Malfunction](#collapse-aedf26269f9fd6bea75e) ## Toyota C2318 The Auxiliary Battery voltage is applied to terminal +B when the power switch is on (IG). The Transmission Control ECU outputs this Diagnostic Trouble Code (DTC) when the input voltage drops ### Toyota C2318 Possible Causes 1. Faulty Auxiliary Battery 2. HEV Fuse 3. IGCT Relay 4. Auxiliary Battery harness is open or shorted 5. Auxiliary Battery circuit poor electrical connection ### DTC C2318 Detecting Condition 1. Power switch on (IG) 2. Terminal +B voltage of the transmission control ECU is 9.3 V or less for 1 sec. or more. ![C2318 Wiring Diagram](/uploads/2021/08/C2318-Wiring-Diagram.png) [Toyota C1201 Engine Control System Malfunction](#collapse-5b4b50369f9fd6bea75e) ## Toyota C1201 The fail-safe mechanism prevents VSC and TRAC operations if a problem in the engine control system is detected via the Control Area Network (CAN). The fail-safe is deactivated and the Diagnostic Trouble Code (DTC) is saved when the signals from the engine are entered properly. ### Toyota C1201 Possible Causes 1\. Sequential Multiport Fuel Injection (SFI) System Problems ### Possible Symptoms 1\. Anti-lock Braking System (ABS) Warning Light 2\. Engine Light On (or Service Engine Soon Warning Light) ![Toyota C1201](/uploads/2021/07/Toyota-C1201.jpg) [OBD2 Code Toyota C1256 Accumulator Low Pressure](#collapse-ed9fc2e69f9fd6bea75e) ## Toyota C1256 The accumulator pressure is detected by the Accumulator Pressure Sensor, which is integrated inside the actuator. In the master cylinder solenoid, the Accumulator Pressure Sensor is linked to the Skid Control ECU. The Accumulator Pressure Sensor is monitored by the Skid Control ECU Module. If the Skid Control ECU detects a drop in accumulator pressure, it sets the OBDII code. ### Toyota C1256 Possible Causes 1\. Faulty accumulator pressure sensor 2\. Accumulator pressure sensor harness is open or shorted 3\. Accumulator pressure sensor circuit poor electrical connection 4\. Faulty skid control ECU ### Possible Symptoms 1\. Anti-lock Braking System (ABS) Warning Light 2\. Engine Light On (or Service Engine Soon Warning Light) ![Toyota Prius ABS C1256 Replacement Service in Islamabad](/uploads/2021/07/189324101_5444264678980389_2804083464902788047_n.jpg) [P20CD - Exhaust Aftertreatment Fuel Injector Control Circuit Low Voltage](#collapse-09b3e2769f9fd6bea75e) The exhaust fuel addition injector assembly is installed on the turbocharger sub-output, assembly’s and the feed pump in the supply pump assembly provides low-pressure fuel to the exhaust fuel addition injector assembly. Engine control module sends a signal to the exhaust fuel addition injector assembly, which adds fuel (ECM). Two distinct controllers are utilised with this injector: Forced regeneration and decrease of particulate matter (PM). ECM powers and grounds the exhaust aftertreatment fuel injector’s high and low control circuits. The ECM issues a OBD2 Code when it identifies a malfunction in either of the exhaust aftertreatment fuel injector circuits (DTC) ### P20CD Possible Causes 1\. Faulty Engine Control Module (ECM) 2\. Faulty Exhaust Aftertreatment Fuel Injector 3\. Exhaust Aftertreatment Fuel Injector harness is open or shorted 4\. Exhaust Aftertreatment Fuel Injector circuit poor electrical connection ![P20CD - Exhaust Aftertreatment Fuel Injector Control Circuit Low Voltage](/uploads/2021/07/2.png) [P20CD - Exhaust Aftertreatment Fuel Injector Control Circuit Low Voltage](#collapse-df07eba69f9fd6bea75e) The exhaust fuel addition injector assembly is installed on the turbocharger sub-output, assembly’s and the feed pump in the supply pump assembly provides low-pressure fuel to the exhaust fuel addition injector assembly. Engine control module sends a signal to the exhaust fuel addition injector assembly, which adds fuel (ECM). Two distinct controllers are utilised with this injector: Forced regeneration and decrease of particulate matter (PM). ECM powers and grounds the exhaust aftertreatment fuel injector’s high and low control circuits. The ECM issues a OBD2 Code when it identifies a malfunction in either of the exhaust aftertreatment fuel injector circuits (DTC) ### P20CD Possible Causes 1\. Faulty Engine Control Module (ECM) 2\. Faulty Exhaust Aftertreatment Fuel Injector 3\. Exhaust Aftertreatment Fuel Injector harness is open or shorted 4\. Exhaust Aftertreatment Fuel Injector circuit poor electrical connection ![P20CD - Exhaust Aftertreatment Fuel Injector Control Circuit Low Voltage](/uploads/2021/07/2.png) [P261B Engine Coolant Pump 'B' Control Malfunction](#collapse-afaf7ee69f9fd6bea75e) OBD2 code P261B stored in the powertrain control module (PCM) when the coolant pump ‘B’ performance goes out of range. The Powertrain Control Module (PCM) monitors the Coolant Pump ‘B’ Control Circuit signal. PCM collects inputs to decide when and for how long the CP-B should be operated. ### P261B Possible Causes 1\. Faulty engine coolant pump 2\. Fault in coolant pump relay 3\. Harness and connector issue in coolant pump 4\. Coolant pump circuit and wiring problems 5\. PCM programming issue ![P261B](/uploads/2021/06/P261B.jpg) [Toyota Engine Bank 1 and Bank 2 A/F and O2 Identification](#collapse-5a0431469f9fd6bea75e) This provides information on the proper identification of engine bank 1 and engine bank 2 for correct A/F sensor and oxygen sensor replacement. Contains information that identifies engine bank 1 and engine bank 2 on the following engines: 1AZ-FE, 2AZ-FE, 2AZ-FE (PZEV), 1GR-FE, 2GR-FE, 2JZ-GE, 1MZ-FE, 3MZ-FE, 1UR-FE, 3UR-FE, 2UZ-FE, 5VZ-FE, and 1ZZ-FE. - Bank 1 (B1) refers to the bank that includes cylinder No. 1. - Bank 2 (B2) refers to the bank opposite bank 1. - Sensor 1 (S1) refers to the sensor that is located before the catalytic converters. - Sensor 2 (S2) refers to the sensor that is located after the catalytic converters. ![Toyota Engine Bank 1 and Bank 2 A/F and O2 Identification](/uploads/2021/07/toyota-sensor-location-9.jpg) [B1503 Exhaust Heat Management Warning Detected](#collapse-37af9b969f9fd6bea75e) ## B1503 Toyota B1503 Diagnostic Trouble Code (DTC) is stored when the Combination Meter Assembly (metre circuit plate) detects a malfunction in the Engine Coolant Temperature Sensor that is linked to the Combination Meter Assembly (metre circuit plate) through a direct connection. When IG voltage is 9.5 V or more and the following condition is detected: 1.Water temperature sensor operation malfunction 2.Water temperature sensor circuit open or short 3.Engine coolant temperature is 120°C (248°F) or more ![b1503 toyota exhaust heat management warning detected](/uploads/2021/06/2021-04-05-12.51.01-scaled.jpeg) [OBD2 Code P0172 Fuel System Too Rich](#collapse-f932c0e69f9fd6bea75e) ## P0172 code definition P0172 is a trouble code that is set when the ECU detects too much gasoline in the engine’s air-fuel mixture. OBD2 code P0172 indicates that the exhaust gases exiting the combustion chamber contain an excessive amount of gasoline. The mass air flow sensor (MAF), oxygen sensors, and manifold absolute pressure (MAP) all used by the ECU to keep track of the engine’s air-fuel ratio. For V6, V8 and V10 engines, Bank 1 is located at the side of the engine that contains cylinder #1. ![p0172](/uploads/2021/06/p0172.jpg) [P07BE Transmission Park Position Sensor/Switch A/B Circuit Correlation](#collapse-9216e0469f9fd6bea75e) ## DTC P07BE Honda The Powertrain Control Module (PCM) identified a correlation issue between the “A” and “B” transmission park location sensor/switch circuits, resulting in this code. This code triggered by the PCM is determined by the particular circumstance, and the check engine light or the service engine soon light will illuminate. Transmission park location sensor/switch circuit is used to keep track of the transmission’s state. When the transmission is in the park spot, this circuit sends a signal to the PCM. This circuit is usually a safety mechanism that prevents the starter from activating when the automatic transmission is in gear, depending on the engine. ![P07BE Transmission Park Sensor](/uploads/2021/05/P07BE-Transmission-Park-Sensor.jpg) [P1634 Motor Power Inverter (MPI) Signal Circuit Malfunction](#collapse-1c56a4a69f9fd6bea75e) ## OBD2 Code P1634 Honda Fit Honda Fit hybrid having DTC P1634 means that the vehicle has problem in hybrid system. The hybrid system is controlled by a range of multiple ECM,s. Most of the time this code corresponds to a faulty IMA module or the DC-DC converter itself. Diagnostics of the system can reveal the exact problem area. This DTC is also set if the 12V auxiliary power battery becomes weak. Sometimes This causes the vehicle to run in a failsafe environment and performance becomes very poor. ![P1634 Honda Fit](/uploads/2021/05/P1634-Honda-Fit.png) [OBD2 Code C2304 Open Or Short Circuit In U Phase](#collapse-ffa907769f9fd6bea75e) The shift control actuator assy consists of the parking lock motor and the rotation angle sensor. Transmission control ECU receives a P position switch signal from the hybrid vehicle control ECU and activates the parking lock motor by controlling current, causing the parking lock mechanism to switch. The transmission control ECU outputs this DTC when it detects a malfunction in the parking lock motor system. **DTC C2304 Detecting Condition** - Power switch on (IG). (Battery voltage is 8 V or more) - Voltage of transmission control ECU terminal MUA is 6 V or less for 1 sec. or more **Trouble Area** - Shift control actuator assy - Wire harness or connector - Transmission control ECU assy - Transaxle parking lock control relay ![C2304 toyota](/uploads/2021/04/C2304.png) [OBD2 Code: P1670 Injection Pump System Malfunction](#collapse-50798b069f9fd6bea75e) When the ignition switch was turned ON, or when the ECM determines whether it is an error of RAM in ECM or not, the ECM conducts a single communication. If any one of the following status occurs in the communication, the ECM conducts one more communication. While the ECM is conducting the communication, if (a) is duplicated 20 times continuously, or if (b) is duplicated 20 times continuously, or if (c) is duplicated 2 times continuously, the ECM outputs the OBD2 code P1670. 1. There was a communication error when receiving data. 2. Data sent from the injection pump correction unit does not match to the data received from the ECM. 3. Data received from the pump ROM is not input in the period of 1024 msecond. Although the determining process is completed without a problem, the ECM conducts the communication again if an undefined code is found while checking an identification code of the receiving data. If the undefined code was duplicated 20 times in a row, the ECM outputs the DTC. ![dtc P1670 Wiring Diagram](/uploads/2021/04/p1670-Wiring-Diagram.png) P1670 Wiring Diagram [SAP P2442 Toyota Landcruiser and Prado](#collapse-97d805e69f9fd6bea75e) The secondary air intake system is part of a vehicle’s emissions control system and can sometimes trigger OBD2 code [P0420.](https://www.youtube.com/watch?v=G52AbdtuRTY) It works to support the function of the catalytic converter. The switching valves allow the air pump to pump air into the exhaust stream when an engine is cold, speeding up the process of warming the catalytic converter to burn unused fuel. We have permanent solution for the catalytic and the air injection pump for vehicles having dual exhaust. Diagnostic trouble codes P2442 and P2440 along with P0420 fix is available. ![OBD2 dtc SAP P2442](/uploads/2020/09/1-5-1.jpg) [B2AA0-92 CTBA City Brake Active System](#collapse-5732d6969f9fd6bea75e) Commonly known as brake orders are issued too often, this error is caused when the collision mitigation system or cross traffic monitoring cameras / radars assess a possible collision. It is very common in Pakistan as we have multiple types of fast approaching vehicles at intersections. The system can reset on its own, if not calibrations maybe required. It is also called cross traffic braking assist at some places. [OBD2 Code: B12C5 Honda Smart key](#collapse-f60ae5e69f9fd6bea75e) Possible failure area is Engine Start / Stop button, however low smart key battery or a bad Key decoder (antenna) can also cause this error. The smart key module is hidden behind the odometer. ![B12C5 Honda Smart key](/uploads/2020/09/3-4.jpg) [OBD2 Code: P0420 Toyota Prius](#collapse-345d77a69f9fd6bea75e) As the P0420 code states, whenever the catalytic choked to a stage that the vehicle performance is greatly compromised this code will set in. The catalytic is cleaned and re-installed. Sometimes this code of P0420 also sets in if the oxygen sensors on the cat-con have stopped functioning. We also provide permanent delete function of this OBD2 code P0420. [P2788 Honda Vezel and Honda Fit](#collapse-f00a22c69f9fd6bea75e) Transmission adaptive learning code, please do not ignore this code as this can lead to permanent failure of your dry clutch or dual clutch transmission. Replenish the fluid with Honda DW1 ATF not CVT. We have recovered many cars poured with wrong oil which may cause permanent damage to an expensive gearbox. Re-calibration is always recommended whenever new oil is poured. [C1391 Prius ABS Fault Abnormal Leak in Accumulator](#collapse-92a076a69f9fd6bea75e) Toyota Prius 2010 vehicles had a factory defect that caused leakage of nitrogen from the pressure system effecting the braking of the vehicle. We upgrade the ABS units with a 2013 model in case the following errors are seen. Please note that ABS unit needs to be calibrated very precisely. We also recommend to replenish the brake fluid on time to keep the ABS unit healthy. [OBD2 Code P0300 P0301 Honda and Toyota Cylinder Misfire](#collapse-119d54e69f9fd6bea75e) P0300 is OBD2 trouble code for Random/Multiple Cylinder Detected. P0301 shows that Cylinder number 1 experiencing  misfire. A popular error on Honda vehicles that may show up if the coil packs of your car are at an end. Replace the bad coils or the complete set and check with an ohm meter before installation. P0351 is code for no 1 coil circuit malfunction. [P0A7F HV Battery Capacity Serious Deterioration](#collapse-1c414d369f9fd6bea75e) This DTC error will come up if the traction battery of your Honda Civic or Insight has completed its life cycle. It is recommended to change the pack ASAP to protect other electronics that may heat up and cause further deterioration of expensive controllers. ![diagnostic trouble codes](/uploads/2020/09/8.jpg) [C1259 HV Control System Regenerative Malfunction](#collapse-fff125e69f9fd6bea75e) ![dtc c1259](/uploads/2020/09/9.jpg) [OBD2 Code C1242 Open Circuit in IG1/IG2](#collapse-943de6e69f9fd6bea75e) If there is a problem with the master cylinder solenoid (skid control ECU) and its power supply circuit. The skid controls ECU stores the diagnostic trouble codes and brings vehicle operation under the fail-safe condition. If the voltage supplied to terminal IG2 is not within the DTC detection range due to malfunctions in parts such as the battery and generator circuit, this OBD2 codes will be present. In Simple terms always check the standard 12V battery condition and measure the voltages when the car is ON and when OFF to ascertain whether it is getting charged or not and then move on to the ABS unit. ![Detecting conditions](/uploads/2020/09/10.jpg) [P3190 Poor Engine Power](#collapse-e4583d169f9fd6bea75e) From the HV ECU, the ECM receives data such as power output required for the engine (required output), estimated torque produced by the engine (estimated torque), engine RPM of control target (target RPM), whether the engine is in start mode or not. Then, based on the required output and target RPM, the ECM calculates a target torque that is to be produced by the engine and compares it with the estimated torque. If the estimated torque is very low compared with the target torque, or the engine start mode continues for the specific duration calculated by water temperature, an abnormal condition is detected. ![Diagnostic trouble code](/uploads/2020/09/11.jpg) [OBD2 Code P0A80 Toyota Prius Hybrid Battery](#collapse-24646ea69f9fd6bea75e) When a OBD2 code [P0A80](/p0a80-prius-code-means-replace-hybrid-battery-pack/) is read / stored in system, it means that the ECM has detected a malfunction in the hybrid vehicle battery management system (HVBMS). This code indicates that a cell has gone weak in the hybrid battery pack. Hybrid vehicles (which do not require external charging) utilize nickel metal-hydride battery packs. Battery packs are actually blocks of batteries (modules) that are wired together using sections of connectors or cables. The typical HV battery is composed of eight (1.2-volt) cells in series. Twenty-eight modules make up the typical HV battery pack. The voltages are from 205VDC to 236VDC between the inverter and the power extractors, safety measures must be taken to avoid permanent damage or injury to the persons performing work on HV car. ![P0A80 prius](/uploads/2020/09/12-e1620627403527.jpg) [OBD2 Code P0420 Catalyst System Efficiency Below Threshold](#collapse-f88f3fe69f9fd6bea75e) The catalytic converter has an oxygen sensor in front and behind it. When the vehicle is warm and running in closed loop mode, the upstream oxygen sensor waveform reading should fluctuate. The downstream O2 sensor reading should be fairly steady. Typically the OBD2 code P0420 triggers the Check Engine Light if the readings of the two sensors are similar. Oxygen sensors are also referred to as O2 sensors. ![OBD2 dtc p0420 catalytic converter](/uploads/2020/09/13.jpg) [C1406 2010 Toyota Fj Cruiser Description](#collapse-9f9303e69f9fd6bea75e) The speed sensor detects the wheel speed and sends the appropriate signals to the Skid Control ECU. These signals are used for brake control. The speed sensor rotors have rows of alternating N and S magnetic poles and their magnetic fields change when the rotors turn. Each speed sensor detects that magnetic change and sends a pulse signal to the Skid Control ECU. [Ford Ranger Wild Track Adblue Off](#collapse-b31e11b69f9fd6bea75e) Ford Ranger Wild track P204F is a Euro6 Compliant vehicle. It comes equipped with an [Adblue](/toyota-adblue-in-diesel-prado-hiace/) SCR system. The system P1575-A1 is famous for causing reliability problems. Some times the car gets into a No-start position and the only option is to repair or replace the necessary components. The engine is a famous Duratorq Turbo Diesel. We deleted the Adblue fluid monitoring system from its computer and permanently resolved the issue. [P2583 CTBA Radar Aiming](#collapse-c7069bd69f9fd6bea75e) P2583 Millimeter Wave Radar is a DTC related to driving support system Radar malfunction, It can also cause malfunction in adaptive cruise as well as early haptic feedback on the RFP pedal. Contact our teams for a complete solution to the CTBA system. We also do cruise limit unlock (110km limit unlock) on Honda Hybrids.