DTC P0122 - Throttle Position (TP) Circuit Low Input

NOTE: If DTC P0107, P0122 and/or P0450 are set together, Light Green wire (sensor reference voltage) may be open.

Connect scan tool to Data Link Connector (DLC). Start engine and allow it to reach normal operating temperature. Observe throttle valve opening percentage on scan tool. If display reads 2 percent or less, go to next step. If display reading is greater than 2 percent, check for an intermittent problem. See TESTS W/O CODES article.
Turn ignition off. Disconnect harness connector from TP sensor. Turn ignition on. Using a voltmeter, measure voltage between ground and Light Green wire at TP sensor harness connector. If reading is 4-6 volts, go to next step. If reading is not as specified, check Light Green wire for an open or short to ground. Repair as necessary. Retest system.
Turn ignition off. Unplug PCM connector "B". Using an ohmmeter, check for continuity between Light Green/Black wire at TP sensor harness connector and PCM harness connector "B", terminal No. 9. If continuity exists, go to next step. If continuity does not exist, check Light Green/Black wire for an open or poor connection. Repair as necessary. Retest system.
Check for continuity between Light Green/White wire at TP sensor harness connector and PCM harness connector "B", terminal No. 6. If continuity exists, go to next step. If continuity does not exist, check Light Green/White wire for an open or poor connection. Repair as necessary. Retest system.
Using an ohmmeter, measure resistance between specified TP sensor terminals. See Figure . Replace TP sensor if resistance is not as specified. See TP SENSOR RESISTANCE table. If resistance is as specified, replace PCM. Retest system.