C2318 — OBD2 Diagnostic Trouble Code (Toyota)

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.