Normal Operation and Fault Conditions
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With the ignition ON, the ABS module sends messages to the SASM over the HS-CAN 2. If the SASM does not receive these messages within a certain time frame (usually less than 1 second), the SASM sets DTCs. For information on the messages sent to the SASM by the ABS module, refer to the Network Message Chart in Description and Operation of the Anti-Lock Brake System (ABS) and Stability Control article.
PPT AX SASM DTC FAULT TRIGGER CONDITIONS
| DTC | Description | Fault Trigger Conditions |
|---|---|---|
| U0121:00 | Lost Communication With Anti-Lock Brake System (ABS) Control Module: No Sub Type Information | Sets in continuous memory and on-demand when the SASM detects any of the ABS module messages are missing. This can be due to a ABS module failure, a circuit failure on the HS-CAN or an excessive load on the network. |