P0122
DTC P0122: TP Sensor Circuit Low VoltageNOTE: 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 wires 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. Measure voltage between TP sensor 3P connector terminals No. 1 and No. 3.
Is there about 5 V?
YES - Go to step 7.
NO - Go to step 13.
7. Turn the ignition switch OFF.
8. At the sensor side, measure resistance between TP sensor 3P connector terminals No. 1 and No. 2 with the throttle fully closed.
Is there about 0.5 - 0.9 kOhm?
YES - Go to step 9.
NO - Replace the throttle body.
9. Measure resistance between TP sensor 3P connector terminals No. 2 and No. 3 with the throttle fully closed.
Is there about 4.5 kOhm?
YES - Go to step 10.
NO - Replace the throttle body.
10. Reconnect the TP sensor 3P connector.
11. Turn the ignition switch ON (II).
12. Measure voltage between ECM connector terminals C18 and C27.
Is there about 0.3 V when the throttle is fully closed and about 4.5 V when the throttle is fully opened?
YES - Substitute a known-good ECM and recheck. If the TP sensor voltage is now normal, replace the original ECM.
NO - Repair short in the wire between the ECM (C27)and the TP sensor.
13. Measure voltage between ECM connector terminals C18 and C28.
Is there about 5 V?
YES - Repair open in the wire between the ECM (C28)and the TP sensor.
NO - Substitute a known-good ECM and recheck. If the prescribed voltage is now available, replace the original ECM.