Normal Operation and Fault Conditions
WARNING: This page is about a different car, the 2019 Ford F-550 Super Duty, 2019 Ford F-450 Super Duty, 2019 Ford F-350 Super Duty, and 2019 Ford F-250 Super Duty. However, it is still accessible from the selected car via links, so may be relevant.
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.
DTC DESCRIPTION
| 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. |