Advanced Diagnostics

Advanced Diagnostics

DTC U0122: F-CAN Malfunction (Powertrain Control Module (PCM)-VSA Modulator-Control Unit)






General Description
The controller area network (CAN) transmits/receives pulsing signals to/from the control modules simultaneously by using two signal lines (CANH and CANL). When the powertrain control module (PCM) does not receive the signals via the CAN lines for a set time or more, the PCM detects a malfunction and a DTC is stored.

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






Enable Conditions






Malfunction Threshold
No signals from the VSA modulator-control unit via the CAN lines are received for at least 1 second, or received data are abnormal at least 20 times.

Diagnosis Details

Conditions for setting the DTC
When a malfunction is detected, a Pending DTC, a Confirmed DTC and the freeze data are stored in the PCM memory. The MIL does not come on.

Conditions for clearing the DTC
The Pending DTC, the Confirmed DTC, and the freeze data can be cleared with the scan tool Clear command or by disconnecting the battery.