Antilock Brake Module (ABS)

C2312-TCS/ESP SWITCH STUCK







- When Monitored:
With the ignition on.

- Set Condition:
When the Anti-Lock Brake Module indicates that the ESP/TCS Switch is low for 30 seconds.





1. ESP/TCS SWITCH CIRCUIT

NOTE: If any other DTCs are present they must be repaired before continuing.

1. Turn the ignition on.
2. Turn the ESP/TCS switch on then off.
3. Check for car icon on solid in cluster and pressing ESP/TCS switch does not change state.
4. With the scan tool, read the switch state for the ESP/TCS switch with NO pressure on the brake, read and record DTCs.

Does the scan tool display switch state indicating pressed?

Yes

- Go To 2

No

- The condition that caused the symptom is currently not present. Inspect the related wiring for a possible intermittent condition. Look for any chafed, pierced, pinched, or partially broken wires.
- Perform the ABS-INTERMITTENT CONDITION TEST. ABS Intermittent Condition Test.

2. (Z906) OPEN CIRCUIT




1. Turn the ignition off.
2. Disconnect the ESP/TCS switch.
3. Using a 12-volt test light connected to 12-volts, check the (Z906) ground circuit.

Does the test light illuminate brightly?

Yes

- Go To 3

No

- Repair (Z906) ground circuit for an open circuit or high resistance.
- Perform ABS VERIFICATION TEST. ABS Verification Test.

3. CHECK FOR A STUCK ESP/TCS SWITCH




1. Turn the ignition off.
2. Measure the internal resistance of the ESP/TCS Switch between the (B46) ESP/TCS control circuit and (Z906) Ground circuit.

Is the resistance below 5.0 ohms?

Yes

- Replace the ESP/TCS Switch.
- Perform ABS VERIFICATION TEST. ABS Verification Test.

No

- Go To 4

4. ESP/TCS CONTROL CIRCUIT




1. Turn the ignition off.
2. Disconnect the ESP/TCS Switch.
3. Disconnect the Anti-Lock Brake Module harness connector.
4. Measure the resistance of the (B46) ESP/TCS control circuit to ground.

Is the resistance below 5.0 ohms?

Yes

- Repair the (B46) ESP/TCS control circuit for a short to ground.
- Perform ABS VERIFICATION TEST. ABS Verification Test.

No

- Replace the Anti-Lock Brake Module.
- Perform ABS VERIFICATION TEST. ABS Verification Test.