P0122
DTC P0122: TP Sensor Circuit Low Voltage1. Turn the ignition switch ON (II).
2. Check the throttle position with the scan tool.
Is there about 10% or 0 - 5 V when the throttle is fully closed and about 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 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 the TP sensor 3P connector terminals No.1 and No.3.
Is there about 5 V?
YES - Go to step 7.
NO - Go to step 14.
7. Turn the ignition switch OFF.
8. At the sensor side, measure resistance between the TP sensor 3P connector terminals No.2 and No.3 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 the TP sensor 3P connector terminals No.1 and No.2 with the throttle fully closed.
Is there about 4.5 kOhm?
YES - Go to step 10.
NO - Replace the throttle body.
10. Disconnect ECM/PCM connector A (31P).
11. 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 (A15) and the TP sensor.
NO - Go to step 12.
12. Connect ECM/PCM connector terminal A15 and body ground with a jumper wire.
13. At the wire harness side, check for continuity between the TP sensor 3P connector terminals No.2 and body ground.
Is there continuity?
YES - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.
NO - Repair open in the wire between the ECM/PCM (A15) and the TP sensor.
14. Measure voltage between ECM/PCM connector terminals A10 and A20.
Is there about 5 V?
YES - Repair open in the wire between the ECM/PCM (A20) and the TP sensor.
NO - Update the ECM/PCM if it does not have the latest software, or substitute a known-good ECM/PCM, then recheck. If the symptom/indication goes away with a known-good ECM/PCM, replace the original ECM/PCM.