FixVault

Pinpoint Test K : DTC U0121: Notes

Refer to Module Communications Network for schematic and connector information.

Normal Operation and Fault Conditions 

The ABS, GSM and TRCM use information contained in messages on the HS-CAN.

NOTE: If a GSM self-test is to be performed, make sure the drivers door is closed and locked.

DTC Fault Trigger Conditions 

DTC Description Fault Trigger Conditions
U0121 Lost Communication With Anti-Lock Brake System (ABS) Control Module This DTC sets if the TRCM and/or the GSM does not receive some or all of an expected message from the ABS module.

Possible Sources