C121D-BRAKE PRESSURE SENSOR CIRCUIT

For a complete wiring diagram Refer to Section 8W.

When Monitored:
With the ignition on.
Set Condition:
When the Anti-Lock Brake Module indicates that the Brake Pressure Sensor Signal is out of range.

Possible Causes

AIR IN BRAKE SYSTEM/WORN MECHANICAL COMPONENTS

ECU INTERNAL FAILURE

ICU INTERNAL FAILURE

Diagnostic Test

1.CHECK FOR A DTC C121D-BRAKE PRESSURE SENSOR CIRCUIT

NOTE: This DTC must be active for the results of this test to be valid.

Does the scan tool display: C121D-BRAKE PRESSURE SENSOR CIRCUIT?

Yes

Go To 2

Refer to the INTERMITTENT CONDITION diagnostic procedure.
Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).

2.CHECK FOR AIR IN BRAKE SYSTEM AND WORN MECHANICAL COMPONENTS

NOTE: Before continuing the brake system must be bled to verify there is no air in the brake system.

NOTE: Visually inspect for worn brake linings, undersized rotors, binding or frozen calipers. Repair as necessary.

If no problem was found above replace the Anti-Lock Brake Module in accordance with the Service Information. Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).

Continue

Go to 3

3. RECHECK FOR A DTC C121D-BRAKE PRESSURE SENSOR CIRCUIT

Does the scan tool display: C121D-BRAKE PRESSURE SENSOR CIRCUIT?

Yes

Replace the ICU in accordance with the Service Information.
Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).

Test complete