P0123

DTC P0123: TP Sensor Circuit High Voltage

NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.

1. Turn the ignition switch ON (II).
2. Check the throttle position with a scan tool or the HDS.

Is there about 6 % when the throttle is fully closed and about 90 % when the throttle is fully opened?

YES - Intermittent failure, system is OK at this time. Check for poor connections or loose terminals at the TP sensor and at the ECM.

NO - Go to step 3.

3. Turn the ignition switch OFF.
4. Disconnect the TP sensor 3P connector.
5. Turn the ignition switch ON (II).




6. At the wire harness side, measure voltage between TP sensor 3P connector terminals No. 1 and No. 3.

Is there about 5 V?

YES - Replace the throttle body.

NO - Go to step 7.




7. Measure voltage between ECM connector terminals C18 and C28.

Is there about 5 V?

YES - Repair open in the wire between the ECM (C18)and the TP sensor.

NO - Substitute a known-good ECM and recheck. If the prescribed voltage is now available replace the original ECM.