C1073

C1073-ABS PUMP MOTOR CONTROL CIRCUIT







- When Monitored:
When the ABS Pump Motor is activated.

- Set Condition:
The ABM detects low pump motor feedback voltage with actuation of the pump motor.





1. 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.

1. Turn the ignition on.
2. With the scan tool, record and erase the DTCs.
3. Cycle the ignition switch from off to on.
4. 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.

5. With the scan tool, read the 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 2

No

- Perform the ABS INTERMITTENT CONDITION TEST Testing and Inspection.

2. INSPECT RELATED WIRING HARNESS, TERMINALS, AND CONNECTORS
1. Turn the ignition off.
2. Visually inspect the related wiring harness. Look for any pinched, chafed, pierced, and partially broken wires.
3. Visually inspect the related wiring harness connectors. Look for broken, bent, pushed out, and corroded terminals.

Were any problems found?

Yes

- Repair as necessary.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

No

- Go To 3

3. CHECK THE ABS PUMP MOTOR FUSED B+ FOR AN OPEN
1. Turn the ignition off.
2. Remove and visually inspect the ABS Pump Motor B+ fuse.

Is the ABS Pump Motor B+ fuse open?

Yes

- Go To 4

No

- Go To 6

4. CHECK THE (A107) FUSED B(+) FOR A SHORT TO GROUND




1. Turn the ignition off.
2. Disconnect the Anti-Lock Brake Module harness connector.
3. 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. ABS Verification Test.

No

- Go To 5

5. CHECK THE (A107) FUSED B(+) CIRCUIT
1. Turn the ignition off.
2. Visually inspect the (A107) Fused B(+) circuit in the wiring harness.
3. Look for any signs of intermittent short to ground.

Is the wiring harness OK?

Yes

- Go To 6

No

- Repair the (A107) Fused B(+) circuit for a short to ground.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

6. CHECK THE VOLTAGE ON THE (A107) FUSED B(+) CIRCUIT




1. Turn the ignition off.
2. Disconnect the Anti-Lock Brake Module harness connector.
3. 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 7

No

- Repair the (A107) Fused B(+) circuit for an open.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

7. CHECK THE (Z931) GROUND CIRCUITS FOR AN OPEN




1. Using a 12-volt test light connected to 12 volts, probe the (Z931) ground circuit.

Does the test light illuminate brightly?

Yes

- Go To 8

No

- Repair the high resistance in the affected circuit.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

8. REPLACE ANTI-LOCK BRAKE MODULE AND VERIFY IF DTC IS STILL ACTIVE
1. Replace the Anti-Lock Brake Module.
2. Perform the ABS VERIFICATION TEST. ABS Verification Test.
3. Turn the ignition on.
4. With the scan tool, read ABS DTCs.

Does this DTC reset?

Yes

- Replace the Hydraulic Control Unit.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

No

- Perform the ABS VERIFICATION TEST. ABS Verification Test.