P0122
DTC P0122: TP Sensor Circuit Low Voltage1. Start the engine. Hold the engine at 3,000 rpm with no load (in Park or neutral) until the radiator fan comes on then turn the ignition switch OFF.
2. Turn the ignition switch ON (II).
3. Check the throttle position with the scan tool.
Is there approx. 10% or 0.5 V when the throttle is fully closed and approx. 90% or 4.5 V 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/PCM.
NO - Go to step 4.
4. Turn the ignition switch OFF.
5. Disconnect the TP sensor connector.
6. Turn the ignition switch ON (II).
7. Measure voltage between TP sensor 3P connector terminals No.1 and No.3.
Is there approx. 5 V ?
YES - Go to step 8.
NO - Go to step 15.
8. Turn the ignition switch OFF.
9. At the sensor side, measure resistance between TP sensor 3P connector terminals No.1 and No.2 with the throttle fully closed.
Is there approx. 0.5 - 0.9 kOhm ?
YES - Go to step 10.
NO - Replace the throttle body (The TP sensor is not available separately.).
10. Measure resistance between TP sensor 3P connector terminals No.2 and No.3 with the throttle fully closed.
Is there approx. 4.5 kOhm ?
YES - Go to step 11.
NO - Replace the throttle body (The TP sensor is not available separately.).
11. Disconnect ECM/PCM connector (31P).
12. At the wire harness side, check for continuity between TP sensor 3P connector terminal No.2 and body ground.
Is there continuity?
YES - Repair short in the wire between the ECM/PCM (C27) and the TP sensor.
NO - Go to step 13.
13. Connect ECM/PCM connector terminal C27 and body ground with a jumper wire.
14. At the wire harness side, check for continuity between TP sensor 3P connector terminal No.2 and body ground.
Is there continuity?
YES - Substitute a known-good ECM/PCM and recheck. If the prescribed voltage is now available, replace the original ECM/PCM.
NO - Repair open in the wire between the ECM/PCM (C27) and the TP sensor.
15. Measure voltage between ECM/PCM connector terminals C18 and C28.
Is there approx. 5V?
YES - Repair open in the wire between the ECM/PCM (C28) and the TP sensor.
NO - Substitute a known-good ECM/PCM and recheck. If the prescribed voltage is now available, replace the original ECM/PCM.