DTC Troubleshooting: P0123 (7) (R18A: M/T)

DTC Troubleshooting: P0123 (7)

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.

1.Turn the ignition switch ON (II).

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 4.


NO - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the throttle body and the ECM/PCM.n


4.Check for Temporary DTCs or DTCs with the HDS.

Are DTC P0123 and P0223 indicated at the same time?


YES - Go to 13.


NO - Go to 5.


5.Turn the ignition switch OFF.

6.Disconnect the throttle body 6P connector.

7.Turn the ignition switch ON (II).

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

 

Is there about 5 V?


YES - Go to 18.


NO - Go to 9.


9.Turn the ignition switch OFF.

10.Jump the SCS line with the HDS.

11.Disconnect ECM/PCM connector C (44P).

12.Check for continuity between ECM/PCM connector terminal C20 and throttle body 6P connector terminal No. 1.

 

Is there continuity?


YES - Go to 25.


NO - Repair open in the wire between the throttle body and the ECM/PCM (C20), then go to 20.

13.Turn the ignition switch OFF.

14.Disconnect the throttle body 6P connector.

15.Jump the SCS line with the HDS.

16.Disconnect ECM/PCM connector C (44P).

17.Check for continuity between ECM/PCM connector terminal C39 and throttle body 6P connector terminal No. 4.

 

Is there continuity?


YES - Go to 25.


NO - Repair open in the wire between the throttle body and the ECM/PCM (C39), then go to 20.

18.Turn the ignition switch OFF.

19.Replace the throttle body.

20.Reconnect all connectors.

21.Turn the ignition switch ON (II).

22.Reset the ECM/PCM with the HDS.

23.Do the ECM/PCM idle learn procedure.

24.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0123 is indicated, check for poor connections or loose terminals at the throttle body and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n


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

26.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P0123 is indicated, check for poor connections or loose terminals at TP sensor A and the ECM/PCM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - If the ECM/PCM was updated, troubleshooting is complete. If the ECM/PCM was substituted, replace the original ECM/PCM.n