LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Ford >> 2021 >> Mustang Mach 1, Automatic Trans >> Repair and Diagnosis >> External Pages >> Different car >> Section 748 (Anti-Lock Brake System (Abs) And Stability Control) >> Diagnosis And Testing >> Anti-Lock Brake System (ABS) and Stability Control >> Pinpoint Tests >> Pinpoint Test Av: Abs Module Communication Concern With GSM
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Pinpoint Test Av: Abs Module Communication Concern With GSM

WARNING: This page is about a different car, the 2021 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

Normal Operation and Fault Conditions 

With the ignition ON, the GSM sends 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 GSM 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 GSM, refer to the Network Message Chart  .

DTC Fault Trigger Conditions 

DTC Description Fault Trigger Condition
ABS U0103:00 Lost Communication With Gear Shift Control Module A: No Sub Type Information This DTC sets when the ABS module does not receive any messages from the GSM within the allowed time.
ABS U0404:00 Invalid Data Received from Gear Shift Control Module A: No Sub Type Information This DTC sets when the ABS module does not receive any messages from the GSM within the allowed time.

Possible Sources 

PINPOINT TESTS AV: ABS MODULE COMMUNICATION CONCERN WITH THE GSM