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No Response From ABS (Antilock Brake Module)

NO RESPONSE FROM ABS


No Response From ABS:





POSSIBLE CAUSES
- (A107) (A111) Fused B(+) circuit open or shorted
- (Z107) (Z923) Ground circuit open
- (F500) Fused ignition sw output circuit open or shorted
- (D65) CAN C BUS (+) circuit open
- (D64) CAN C BUS (-) circuit open
- Antilock brake module

Diagnostic Test

1. TEST FOR INTERMITTENT CONDITION
Turn the ignition on.

NOTE: Ensure the IOD fuse is installed and battery voltage is between 10.0 and 16.0 volts.

With the scan tool, select ECU view.

NOTE:
- A red X will be next to the module that is not communicating, indicating that the module is not active on the Bus network. A green check indicates that the module is active on the Bus network.
- Check the FCM for any active CAN C hardware DTCs, perform DTC before proceeding.

Q: Does the scan tool display a red X next to the module?

YES: Go To 2
NO: The no response condition is not present at this time. Using the wiring diagram/schematic as a guide, inspect the wiring for chafed, pierced, pinched, and partially broken wires and the wiring harness connectors for broken, bent, pushed out, and corroded terminals.

2. (A107) (A111) FUSED B(+) CIRCUIT OPEN OR SHORTED




Turn the ignition off.
Disconnect the Antilock Brake Module harness connector.
Using a 12-volt test light connected to ground, check each (A107) and (A111) Fused B(+) circuit.

Q: Does the test light illuminate brightly for each circuit?

YES: Go To 3
NO: Repair the Fused B(+) circuit for an open or short.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test

3. (Z107) (Z923) GROUND CIRCUIT OPEN




Using a 12-volt test light connected to 12-volts, check each (Z107) and (Z923) ground circuit.

Q: Does the test light illuminate brightly for each circuit?

YES: Go To 4
NO: Repair the ground circuit for an open.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test

4. (F500) FUSED IGNITION SWITCH OUTPUT CIRCUIT OPEN OR SHORTED




Turn the ignition on.
Using a 12-volt test light connected to ground, check the (F500) Fused Ignition Switch Output circuit.

Q: Does the test light illuminate brightly?

YES: Go To 5
NO: Repair the Fused Ignition Switch Output circuit for an open or short.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test

5. (D65) CAN C BUS (+) CIRCUIT OPEN




Turn the ignition off.
Disconnect the FCM C1 harness connector.
Measure the resistance of the (D65) CAN C Bus (+) circuit between the FCM connector and the Antilock Brake Module connector.

Q: Is resistance below 5.0 ohms?

YES: Go To 6
NO: Repair the (D65) CAN C Bus (+) circuit for an open.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test

6. (D64) CAN C BUS (-) CIRCUIT OPEN




Measure the resistance of the (D64) CAN C Bus (-) circuit between the FCM connector and the Antilock Brake Module connector.

Q: Is resistance below 5.0 ohms?

YES: Replace the Antilock Brake Module.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test
NO: Repair the (D64) CAN C Bus (-) circuit for an open.
Perform ABS VERIFICATION TEST - VER 1. ABS Verification Test