IMA System

Advanced Diagnostics - DTC U0029 (107): F-CAN Malfunction (BUS-OFF (Motor Control Module (MCM))) (Motor) (IMA System)
DTC U0029 (108): F-CAN Malfunction (BUS-OFF (Motor Control Module (MCM))) (Battery) (IMA System)






General Description
The motor control processor and the battery control processor are in the motor control module (MCM). The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (CANH and CANL). When each processor does not receive the signals via the F-CAN lines for a set time, a malfunction is detected and a DTC is stored.

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






Enable Conditions






Malfunction Threshold
No signals via the F-CAN lines are received for at least 0.5 second.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected during the first drive cycle, a Pending DTC is stored in the MCM memory. If the malfunction returns in the next (second) drive cycle, the MIL comes on and a Confirmed DTC and the freeze data are stored.

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.