Diagnostic Test
- CHECK FOR A DTC C1073-ABS PUMP MOTOR CONTROL CIRCUIT NOTE: This DTC must be active for the results of this test to be valid. If present, diagnose and repair DTC C2116-ABS PUMP MOTOR SUPPLY LOW VOLTAGE before diagnosing this DTC.
- Turn the ignition on.
- Using the scan tool, record and erase DTCs.
- Cycle the ignition switch from off to on.
- Road test the vehicle over 25 mph (40 km/h).NOTE: Vehicle must be driven above 25 mph (40 km/h) for set conditions to be meet.
- Using the scan tool, read DTCs.NOTE: The Anti-Lock Brake Module must sense ALL 4 wheels at 7.5 mph (12 km/h) before it will extinguish the ABS indicators.
Does the scan tool display: C1073-ABS PUMP MOTOR CONTROL CIRCUIT?
Yes
- Go to step 2
No
- Perform the INTERMITTENT CONDITION diagnostic procedure. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
- CHECK THE ABS PUMP MOTOR FUSED B+ FOR AN OPEN
- CHECK THE (A107) FUSED B(+) FOR A SHORT TO GROUND
- Disconnect the Anti-Lock Brake Module harness connector.
- Using a 12-volt test light connected to 12 Volts, probe the (A107) Fused B+ circuit.
Does the test light illuminate brightly?
Yes
- Repair the (A107) Fused B(+) circuit for a short to ground.
- Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
No
- Go to step 4
- CHECK THE (A107) FUSED B(+) CIRCUIT
- Visually inspect the (A107) Fused B(+) circuit in the wiring harness.
- Look for any signs of intermittent short to ground.
Is the wiring harness OK?
Yes
- Go to step 5
No
- Repair the (A107) Fused B(+) circuit for a short to ground.
- Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
- CHECK THE VOLTAGE ON THE (A107) FUSED B(+) CIRCUIT
- Disconnect the Anti-Lock Brake Module harness connector.
- Measure the voltage of the (A107) Fused B(+) circuit in the Anti-Lock Brake Module harness connector.
Is the voltage above 10 Volts?
Yes
- Go to step 6
No
- Repair the (A107) Fused B(+) circuit for an open.
- Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
- CHECK THE (Z107) GROUND CIRCUIT FOR AN OPEN
- Measure the resistance of the (Z107) Ground circuit between the Anti-Lock Brake Module harness connector and ground
Is the resistance below 5.0 Ohms?
Yes
- Replace the ICU per service information.
- Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
No
- Repair the high resistance in the affected circuit.
- Perform the ABS VERIFICATION TEST. See DTC-Based Diagnostics/MODULE, Antilock Brake (ABS) - Standard Procedure .
- Measure the resistance of the (Z107) Ground circuit between the Anti-Lock Brake Module harness connector and ground