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 CIRCUITNOTE: This DTC must be active for the results of this test to be valid.
Turn the ignition on.
With the scan tool, read and record DTCs.
With the scan tool, read and record Freeze Frame information.
With the scan tool, erase DTCs.
Start the engine.
Depress and release the brake pedal.
With the scan tool, read and record DTCs.
Does the scan tool display: C121D-BRAKE PRESSURE SENSOR CIRCUIT?
Yes
- Go To 2
No
- 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
Turn the ignition on.
With the scan tool, read and record DTCs.
With the scan tool, read and record Freeze Frame information.
With the scan tool, erase DTCs.
Start the engine.
Depress and release the brake pedal.
With the scan tool, read and record DTCs.
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).
No
- Test complete