DTC Troubleshooting

DTC Troubleshooting: P0123

DTC P0123:

TP Sensor A Circuit High Voltage

NOTE: Before you troubleshoot, record all freeze data and any on-board snapshot, and review the general troubleshooting information Initial Inspection and Diagnostic Overview.

1. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

2. Clear the DTC with the HDS.

3. Check TP SENSOR A in the DATA LIST with the HDS.

Is there about 4.8 V or more?

YES -

Go to step 4.

NO -

Intermittent failure, the system is OK at this time. Check for poor connections or loose terminals at the throttle body and the PCM.�

4. Check for Pending or Confirmed DTCs with the HDS.

Are DTC P0123 and P0223 indicated at the same time?

YES -

Go to step 13.

NO -

Go to step 5.

5. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

6. Disconnect the throttle body 6P connector.

7. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

8. Measure the voltage between throttle body 6P connector terminal No. 1 and body ground.





Is there about 5 V?

YES -

Go to step 18.

NO -

Go to step 9.

9. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

10. Jump the SCS line with the HDS.

11. Disconnect PCM connector B (49P).

12. Check for continuity between PCM connector terminal B17 and throttle body 6P connector terminal No. 1.





Is there continuity?

YES -

Go to step 25.

NO -

Repair an open in the wire between the throttle body and the PCM (B17), then go to step 20.

13. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

14. Disconnect the throttle body 6P connector.

15. Jump the SCS line with the HDS.

16. Disconnect PCM connector B (49P).

17. Check for continuity between PCM connector terminal B33 and throttle body 6P connector terminal No. 4.





Is there continuity?

YES -

Go to step 25.

NO -

Repair an open in the wire between the throttle body and the PCM (B33), then go to step 20.

18. Turn the ignition switch to LOCK (0), or press the engine start/stop button to select the OFF mode.

19. Replace the throttle body Removal and Replacement.

20. Reconnect all connectors.

21. Turn the ignition switch to ON (II), or press the engine start/stop button to select the ON mode.

22. Reset the PCM with the HDS.

23. Do the PCM idle learn procedure PCM Idle Learn Procedure.

24. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0123 indicated?

YES -

Check for poor connections or loose terminals at the throttle body and the PCM, then go to step 1.

NO -

Troubleshooting is complete. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�

25. Reconnect all connectors.

26. Update the PCM if it does not have the latest software PCM Update, or substitute a known-good PCM.

27. Check for Pending or Confirmed DTCs with the HDS.

Is DTC P0123 indicated?

YES -

Check for poor connections or loose terminals at the throttle body and the PCM. If the PCM was updated, substitute a known-good PCM, then recheck. If the PCM was substituted, go to step 1.

NO -

If the PCM was updated, troubleshooting is complete. If the PCM was substituted, replace the original PCM Service and Repair. If any other Pending or Confirmed DTCs are indicated, go to the indicated DTC's troubleshooting.�