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Pinpoint Test Ai: Abs Module Communication Concern With Pcm

Normal Operation and Fault Conditions 

With the ignition ON, the PCM sends messages to the ABS module over the FD-CAN. 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 PCM 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 PCM, refer to the Network Message Chart  .

The TCM is an internal component of the PCM.

DTC Fault Trigger Conditions 

DTC Description Fault Trigger Condition
ABS U0100:00 Lost Communication With ECM/PCM "A": No Sub Type Information This DTC sets when the ABS module does not receive any messages from the PCM within the allowed time.
ABS U0401:00 Invalid Data Received from ECM/PCM A: No Sub Type Information This DTC sets when the ABS module receives invalid data in any of the following messages: accelerator pedal, brake pedal, driven wheel torque or neutral tow status.
ABS U0401:64 Invalid Data Received from ECM/PCM A: Signal Plausibility Failure This DTC sets when the ABS module receives invalid data in the gear selector position or driven wheel torque messages.
ABS U0401:86 Invalid Data Received from ECM/PCM A: Signal Invalid This DTC sets when the ABS module receives invalid data in the accelerator pedal message.
ABS U0402:86 Invalid Data Received from TCM: Signal Invalid This DTC sets when the ABS module receives invalid data in the gear lever position, neutral tow command or the selectable drive mode switch type message.

Possible Sources 

Pinpoint Tests AI: ABS Module Communication Concern With PCM