C121E

C121E-BRAKE PRESSURE SENSOR COMPARATIVE PERFORMANCE



- 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.





1. CHECK FOR A DTC C121E-BRAKE PRESSURE SENSOR COMPARATIVE PERFORMANCE

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

1. Turn the ignition on.
2. With the scan tool, read and record the DTCs.
3. With the scan tool, read and record the Environmental Data to help identify the conditions in which the DTC was set.
4. With the scan tool, erase the DTCs.
5. Start the engine.
6. Slowly press and release the brake pedal.
7. With the scan tool, read and record the DTCs.

Does the scan tool display: C121E-BRAKE PRESSURE SENSOR COMPARATIVE PERFORMANCE?

Yes

- Go To 2

No

- Perform the ABS-INTERMITTENT CONDITION TEST. ABS Intermittent Condition Test.

2. HCU/ECU ISOLATION
1. Turn the ignition off.
2. Separate the ECU from the HCU.
3. Turn the ignition on.
4. With the scan tool, monitor the brake pressure.

Does the scan tool display brake pressure above 218 bar (3162 psi)?

Yes

- Replace the HCU.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.

No

- Replace the ECU.
- Perform the ABS VERIFICATION TEST. ABS Verification Test.