Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
Pinpoint Test As: Abs Module Communication Concern With FCIM
Normal Operation and Fault Conditions
With the ignition ON, the FCIM sends messages to the GWM over the MS-CAN, The GWM relays these messages to the ABS module over the HS-CAN2. If the ABS module does not receive these messages within the allotted time frame or if the messages contain invalid data, the module sets a DTC. This can be due to a FCIM failure, a circuit failure on the network or an excessive load on the network. For information on the messages sent to the ABS module by the FCIM, refer to the Network Message Chart .
DTC Fault Trigger Conditions
| DTC | Description | Fault Trigger Condition |
|---|---|---|
| ABS U0256:00 | Lost Communication With Front Controls Interface Module "A": No Sub Type Information | This DTC sets when the ABS module does not receive any messages from the FCIM within the allowed time. |
| ABS U0557:00 | Invalid Data Received From Front Controls Interface Module "A": No Sub Type Information | This DTC sets when the ABS module receives messages from the FCIM, but the messages contain invalid data. |
Possible Sources
- Network communication concern
- GWM
- FCIM
Pinpoint Tests AS: ABS Module Communication Concern With FCIM
NO RELATED
Use the Manual With the Right Hardware
Pair factory procedures with proven DIY tools so the instructions are easier to execute.
Affiliate disclosure: We may earn a commission at no extra cost to you.
When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.