138-1
VSA DTC Troubleshooting: 138-1
DTC 138:
Brake Pedal Position Switch Malfunction
NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Reading and Clearing Diagnostic Trouble Codes.
1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
2. Check for DTCs with the HDS.
Is DTC 86 indicated with DTC 138 at the same time?
YES -
Do the DTC 86 troubleshooting 86-1.
NO -
Go to step 3.
3. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.
4. Check the No. 10 (15 A) fuse in the under-hood fuse/relay box.
Is the fuse blown?
YES -
Go to step 5.
NO -
Reinstall the checked fuse, then go to step 15.
5. Short the SCS line with the HDS.
6. Disconnect the PCM connector A (49P) Service and Repair.
7. Disconnect the brake pedal position switch 4P connector Adjustments.
8. Check for continuity between PCM connector A (49P) terminal No. 8 and body ground.
Is there continuity?
YES -
Repair a short to body ground in the wire between the PCM and the brake pedal position switch.
NO -
Go to step 9.
9. Check for continuity between brake pedal position switch 4P connector terminal No. 1 and body ground.
Is there continuity?
YES -
Repair a short to body ground in the wire between the No. 10 (15 A) fuse in the under-hood fuse/relay box and the brake pedal position switch.
NO -
Go to step 10.
10. Reconnect all connectors, then install a new No. 10 (15 A) fuse.
11. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
12. Clear the DTC with the HDS.
13. Start the engine, then press the brake pedal slowly and hard.
14. Check for DTCs with the HDS.
Is DTC 138 indicated?
YES -
Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode, then go to step 21.
NO -
The system is OK at this time.
15. Disconnect the brake pedal position switch 4P connector Adjustments.
16. Measure the voltage between brake pedal position switch 4P connector terminal No. 1 and body ground.
Is there battery voltage?
YES -
Go to step 17.
NO -
Repair an open in the wire between the No. 10 (15 A) fuse in the under-hood fuse/relay box and the brake pedal position switch.
17. Short the SCS line with the HDS.
18. Disconnect the PCM connector A (49P) Service and Repair.
19. Check for continuity between brake pedal position switch 4P connector terminal No. 2 and PCM connector A (49P) terminal No. 8.
Is there continuity?
YES -
Go to step 20.
NO -
Repair an open in the wire between the PCM and the brake pedal position switch.
20. Reconnect all connectors.
21. Do the brake pedal position switch test Testing and Inspection.
Is the brake pedal position switch OK?
YES -
Go to step 22.
NO -
Replace the brake pedal position switch Adjustments.
22. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.
23. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.
24. Clear the DTC with the HDS.
25. Start the engine, then press the brake pedal slowly and hard.
26. Check for DTCs with the HDS.
Is DTC 138 indicated?
YES -
Check for loose terminals in the PCM connector A (49P). If the PCM was updated, substitute a known-good PCM, then retest. If the PCM was substituted, go to step 27.
NO -
If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair.
27. Update the VSA modulator-control unit if it does not have the latest software Testing and Inspection.
28. Start the engine, then press the brake pedal slowly and hard.
29. Check for DTCs with the HDS.
Is DTC 138 indicated?
YES -
Check for loose terminals in the VSA modulator-control unit 46P connector. If the VSA modulator-control unit was updated and the symptom/indication is still present, replace the VSA modulator-control unit Service and Repair.
NO -
If the VSA modulator-control unit was updated, troubleshooting is complete. If any other DTCs are indicated, go to the indicated DTCs troubleshooting.