C1073

C1073-ABS MOTOR CONTROL CIRCUIT





For a complete wiring diagram, refer to the Wiring Information.

- When Monitored:
With the ignition on and no system under voltage condition present.

- Set Condition:
OPEN CIRCUIT: If pump motor feedback remains greater than 0.75 of a volt for more than 50 msec (+/- 5 msec) after monitoring conditions are met, the DTC will set.

LOCKED MOTOR: If the module detects that the motor is spinning at less than 500 r.p.m. after monitoring conditions are met, the DTC will set.

LOW VOLTAGE: The voltage of the supply is monitored every 3 msec. If the voltage is low for 150 msec, the DTC will set.





1. DTC IS ACTIVE
1. Ignition on, engine not running.
2. With the scan tool, clear DTCs.
3. Turn the ignition off to the lock position.
4. Ignition on, engine not running.
5. With the scan tool, actuate the ABS pump motor.

Did the Pump Motor operate when actuated?

No

- Go To 2

Yes

- Go To 5

2. (A107) FUSED B+ CIRCUIT OPEN OR HIGH RESISTANCE




1. Turn the ignition off to the lock position.
2. Disconnect the ABS Module harness connector.

NOTE: Check connector - Clean/repair as necessary.

3. Using a 12-volt test light connected to ground, check the (A107) Fused B+ Circuit.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go To 3

No

- Repair the (A107) Fused B+ Circuit for an open circuit or high resistance. Inspect the related fuse. If the fuse is open, check the circuit for a short to ground.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

3. (Z107) or (Z127) GROUND CIRCUIT OPEN OR HIGH RESISTANCE




1. Using a 12-volt test light connected to 12-volts, check the (Z107) and (Z127) Ground circuits.

NOTE: The test light should be illuminated and bright. Compare the brightness to that of a direct connection to the battery.

Is the test light illuminated and bright?

Yes

- Go To 4

No

- Repair the (Z107) or (Z127) Ground Circuit(s) for an open circuit or high resistance.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

4. ANTI-LOCK BRAKE SYSTEM (ABS) MODULE
1. Turn the ignition off to the lock position.
2. Inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
3. Inspect the related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

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

No

- If no other problems are found, replace the Anti-lock Brake System (ABS) Module.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

5. WIRING HARNESS INSPECTION
1. Turn the ignition off to the lock position.
2. Inspect the related wiring harness. Look for any chafed, pierced, pinched, or partially broken wires.
3. Inspect the related wire harness connectors. Look for broken, bent, pushed out, or corroded terminals.
4. Perform any Technical Service Bulletins that may apply.

Were any problems found?

Yes

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

No

- Test Complete.