A/T

Advanced Diagnostics

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






General Description
The controller area network (CAN) transmits/receives pulsing signals to/from the multiple control modules simultaneously by using two signal lines (CANH and CANL). When the powertrain control module (PCM) does not receive the signals from the VSA modulator-control unit via the CAN lines for a set time, 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 abnormal signals from the CAN lines for at least 20 counts.

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.