Pinpoint Test BC: SASM (Steering Angle Sensor Module) Communication Concern With APIM (Sync Module): Notes
WARNING: This page is about a different car, the 2021 Ford F-150. However, it is still accessible from the selected car via links, so may be relevant.
Refer to VEHICLE DYNAMIC SYSTEMS for schematic and connector information.
Normal Operation and Fault Conditions
REFER to: Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description .
With the ignition ON, the APIM sends messages to the SASM module through the GWM over the HS-CAN3. If the SASM does not receive these messages within a certain time frame or if the messages contain invalid information, the module sets Diagnostic Trouble Codes (DTCs). This can be due to a APIM failure, a circuit failure on the CAN or an excessive load on the network.
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Condition |
|---|---|---|
| SASM U0253:00 | Lost Communication With Accessory Protocol Interface Module: No Sub Type Information | Sets when the SASM does not receive messages from the APIM. |
| SASM U0554:00 | Invalid Data Received From Accessory Protocol Interface Module: No Sub Type Information | Sets if the SASM receives invalid data from the center stack feature configuration message. |
| SASM U0554:82 | Invalid Data Received From Accessory Protocol Interface Module: Alive/Sequence Counter Incorrect/Not Updated | Sets if the SASM receives messages from the APIM indicating "unchanged data". |
Possible Sources
- Network communication concern
- Over or under voltage concerns
- APIM
- GWM