P0555

DTC Troubleshooting: P0555

DTC P0555:

Brake Booster Pressure Sensor Circuit Malfunction

1. Turn the ignition switch to ON (II).

2. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS.

Is it between 0.19 and 4.8 V?

YES -

Intermittent failure, the system is OK at this time. Refer to intermittent failures troubleshooting.

NO -

- If 0.19 V or less is indicated, go to step 3.
- If 4.8 V or more is indicated, go to step 13.

3. Turn the ignition switch to LOCK (0).

4. Disconnect the brake booster pressure sensor 3P connector Service and Repair.

5. Turn the ignition switch to ON (II).

6. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS.

Is 0.19 V or less indicated?

YES -

Go to step 7.

NO -

Go to step 11.

7. Turn the ignition switch to LOCK (0).

8. Short the SCS line with the HDS.

9. Disconnect PCM connector B (44P) Service and Repair.

10. Check for continuity between brake booster pressure sensor 3P connector terminal No. 2 and body ground.





Is there continuity?

YES -

Repair a short to body ground in the wire between the brake booster pressure sensor and the PCM.

NO -

Check for loose terminals and poor connections between the brake booster pressure sensor and the PCM, then update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM Service and Repair.

11. Measure the voltage between brake booster pressure sensor 3P connector terminals No. 1 and No. 3.





Is there about 5 V?

YES -

Replace the brake booster pressure sensor Service and Repair.

NO -

Go to step 12.

12. Measure the voltage between brake booster pressure sensor 3P connector terminal No. 1 and body ground.





Is there 0.1 V or less?

YES -

Repair an open in the wire between the brake booster pressure sensor and the PCM.

NO -

Check for loose terminals and poor connections between the brake booster pressure sensor and the PCM, then update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM Service and Repair.

13. Turn the ignition switch to LOCK (0).

14. Disconnect the brake booster pressure sensor 3P connector Service and Repair.

15. Connect the brake booster pressure sensor 3P connector terminals No. 2 and No. 3 with a jumper wire.





16. Turn the ignition switch to ON (II).

17. Check the BRAKE BOOSTER PRESSURE SENSOR in the DATA LIST with the HDS.

Is 4.8 V or more indicated?

YES -

Go to step 18.

NO -

Replace the brake booster pressure sensor Service and Repair.

18. Disconnect the jumper wire from the brake booster pressure sensor 3P connector.

19. Measure the voltage between brake booster pressure sensor 3P connector terminal No. 2 and body ground.





Is there about 5 V?

YES -

Repair an open in the wire (SG6 line) between the brake booster pressure sensor and the PCM.

NO -

Go to step 20.

20. Turn the ignition switch to LOCK (0).

21. Short the SCS line with the HDS.

22. Disconnect PCM connector B (44P) Service and Repair.

23. Check for continuity between brake booster pressure sensor 3P connector terminal No. 2 and PCM connector B (44P) terminal No. 5.





Is there continuity?

YES -

Check for loose terminals and poor connections between the brake booster pressure sensor and the PCM, then update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM, then go to step 1 and recheck. If no DTCs are indicated, and the PCM was substituted, replace the original PCM Service and Repair.

NO -

Repair an open in the wire between the brake booster pressure sensor and the PCM.