Pinpoint Test J : U0121, U0129, U0415: Notes
Refer to Module Communications Network for schematic and connector information.
Normal Operation and Fault Conditions
When a network message is suspected as missing or confirmed by a missing message DTC (U-code), its important to look for other conditions that may also be present in additional modules throughout the vehicle. Once a DTC sets in the TCM, it may be helpful to review the complete message list available in the Master DTC Chart and see what other modules also rely on the same message and run the self-test for those modules. If the message is missing from other modules, the same DTC may also set in those modules. Confirmation of missing messages common to multiple modules may indicate that the originating module is the source of the concern or the communication network may be experiencing some problems.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| U0121 | Lost Communication With Anti-Lock Brake System (ABS) Control Module | Lost communication with ABS module but the TCM is receiving messages from other modules. |
| U0129 | Lost Communication With Brake System Control Module | Lost communication with ABS module but the TCM is receiving messages from other modules. |
| U0415 | Invalid Data Received From Anti-Lock Brake System (ABS) Control Module | Receiving CAN messages from the ABS but the ABS is indicating failures of certain key signals. |
Possible Sources
- Connectors damaged or pushed-out terminals, corrosion, loose wires and missing or damaged seals
- BJB fuse Refer to Transmission Controls for schematic and connector information.
- Network