C1221-BRAKE PRESSURE SENSOR/ACCEL PEDAL POSITION SENSOR CORRELATION
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 output signal is not plausible.
| Possible Causes |
| AIR IN BRAKE SYSTEM / WORN MECHANICAL COMPONENTS |
| BRAKE SWITCH SIGNAL OPEN |
| BRAKE PRESSURE SENSOR |
| INTEGRATED CONTROL MODULE |
Diagnostic Test
1.CHECK FOR A DTC C1221-BRAKE PRESSURE SENSOR/ACCEL PEDAL POSITION SENSOR CORRELATIONDoes the scan tool display: C1221-BRAKE PRESSURE SENSOR/ACCEL PEDAL POSITION SENSOR CORRELATION?
Yes
- Go To 2
No
- Refer to the INTERMITTENT CONDITION diagnostic procedure.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
2.CHECK BRAKE SWITCH
Did the Brake Switch Signal change?
Yes
- Go To 3
No
- Repair as needed.
3.CHECK BRAKE PRESSURE SENSOR
Did Brake Pressure Sensor increase above 15 bar?
Yes
- Replace the Integrated Control Unit in accordance with the Service Information.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
No
- Go To 4
4.CHECK FOR AIR IN BRAKE SYSTEM
NOTE: Before continuing the brake system must be bled to verify there is no air in the brake system.
Was there any air in the brake system or worn mechanical components?
Yes
- Repair as needed.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).
No
- Replace the Integrated Control Unit in accordance with the Service Information.
- Perform ABS VERIFICATION TEST. (Refer to 5 - BRAKES - STANDARD PROCEDURE).