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Home >> Ford >> 2021 >> Explorer ST >> Repair and Diagnosis >> External Pages >> Different car >> Section 497 (Abs Guided Routine) >> Pinpoint Tests >> Pinpoint Tests BM: ABS Module Communication Concern With ATCM >> Normal Operation and Fault Conditions
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Normal Operation and Fault Conditions

WARNING: This page is about a different car, the 2020 Ford Explorer. However, it is still accessible from the selected car via links, so may be relevant.

With the ignition ON, the ATCM sends messages to the ABS module over the HS-CAN 2. If the ABS module does not receive these messages within a certain time frame (usually less than 1 second), the ABS module sets a DTCs. For information on the messages sent to the ABS module by the ATCM, refer to the Description and Operation in the Anti-Lock Brake System (ABS) and Stability Control article. 

PPT BM ABS MODULE DTC FAULT TRIGGER CONDITIONS

DTC Description Fault Trigger Conditions
U0138:00 Lost Communication With All Terrain Control Module: No Sub Type Information Sets when the ABS module does not receive any messages from the ATCM.
U0138:86 Lost Communication With All Terrain Control Module: Signal Invalid Sets when the ABS module is configured for one type of selectable drive mode switch and the ABS module receives a message for a different type of selectable drive mode switch.
U0138:87 Lost Communication With All Terrain Control Module: Missing Message Sets when the ABS module does not receive the 4x4 switch data message in the alloted time.