DTC P0122: Throttle Position (TP) Sensor Circuit Low Input
- Disconnect TP sensor harness connector. Turn ignition on. Using a voltmeter, measure voltage between ground and Gray/Red wire of TP sensor harness connector. If voltage is 4-5 volts, go to next step. If voltage is not as specified, check Gray/Red wire for an open, short to ground, short to Gray/Yellow wire or poor connection at PCM. Repair as necessary. If wires and connections are okay, replace PCM. Retest system.
- Turn ignition off. Reconnect TP sensor harness connector. Turn ignition on. On models with manual transmission, measure voltage between PCM harness connector "B", terminal No. 17 and ground while moving throttle from idle to fully open position. On models with automatic transmission, measure voltage between PCM harness connector "D", terminal No. 25 and ground while moving throttle from idle to fully open position. If voltage is .35-.65 volt at idle position and 3.5-4.5 volts with throttle fully open, replace PCM. If voltage is a constant 0-1 volt, repair Gray wire for short to Gray/Yellow wire or ground. If voltage is other than described, adjust or replace TP sensor. Retest system.