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Diagnostic Routine AL




Diagnostic Routine AL

Diagnostic Overview

U3003:62 - ABS Module

Refer to Wiring Diagram Set 42 for schematic and connector information Electrical Diagrams.

Normal Operation and Fault Conditions

The ABS (Anti-Lock Brake System) module, hydraulic pump and solenoid valves require an operating voltage that is between 10 and 17 volts. The ABS (Anti-Lock Brake System) module receives this voltage from the BJB (Battery Junction Box). The BCM (Body Control Module) broadcasts a vehicle voltage message on the HS-CAN (High Speed Controller Area Network) for other modules to use as a check for their own voltage inputs. Excessive resistance or an open in the ABS (Anti-Lock Brake System) module voltage circuits, a discharged battery, an inoperative charging system or a communication concern will result in the ABS (Anti-Lock Brake System) module setting a DTC (Diagnostic Trouble Code).

DTC Fault Trigger Conditions






Pinpoint Test

1. CHECK FOR ABS (Anti-Lock Brake System) MODULE BATTERY VOLTAGE DTCs (Diagnostic Trouble Codes)

1. Ignition ON.

2. Using a scan tool, carry out the ABS (Anti-Lock Brake System) module self-test.

Is DTC (Diagnostic Trouble Code) U3003:16 and/or U3003:17 present?






2. CHECK FOR ABS (Anti-Lock Brake System) MODULE COMMUNICATION DTCs (Diagnostic Trouble Codes)

1. Review the results of the previous ABS (Anti-Lock Brake System) module self-test.

Is DTC (Diagnostic Trouble Code) U0140:00 present?






3. CHECK FOR BCM (Body Control Module) BATTERY VOLTAGE DTCs (Diagnostic Trouble Codes)

1. Using a scan tool, carry out the BCM (Body Control Module) self-test.

Is DTC (Diagnostic Trouble Code) U3003:16 and/or U3003:17 present?






4. CHECK THE ABS (Anti-Lock Brake System) MODULE VOLTAGE SUPPLY (VPWR_ABS) PID (Parameter Identification) AND THE BCM (Body Control Module) BATTERY VOLTAGE PID (Parameter Identification)

1. Measure and record the voltage at the battery.

2. Using a scan tool, observe the VPWR_ABS and the V_BATT PIDs (Parameter Identifications).

Do both PIDs (Parameter Identifications) display within 0.2 volt of the recorded battery voltage?