Advanced Diagnostics

Advanced Diagnostics - DTC U0312 (124): BCM, MCM, PGM-FI System Program Version Mismatch

General Description






The motor control processor and the battery control processor softwares which are in the motor control module (MCM) and the FI CPU which is in the powertrain control module (PCM) can be updated by a software rewriting device connected via the F-CAN lines. When the battery control processor and the FI CPU, or the motor control processor need to be updated but either processor fails rewriting, the indicator comes on and stores a DTC. Each processor stores a program version information, and compare their versions to each other by transmitting/receiving via the serial communication. If the battery control processor judges that its own software version is old, a malfunction is detected and a DTC is stored.

Monitor Execution, Sequence, Duration, DTC Type, OBD Status






Enable Conditions






Malfunction Threshold
The battery control processor judges that its own software version is old for at least 1 second.


Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected, the MIL comes on and a Pending DTC, a Confirmed DTC, and the freeze data are stored in the MCM memory.

Conditions for clearing the DTC
The MIL is cleared if the malfunction does not return in three consecutive trips in which the diagnostic runs. The MIL, the Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.