DTC P0123-A: THROTTLE POSITION SENSOR VOLTAGE HIGH Chrysler LHS II

Note. For connector terminal ID, see CONNECTOR IDENTIFICATION . For wiring diagram, see WIRING DIAGRAMS article.

1. Using scan tool, read Throttle Position (TP) sensor voltage. If TP sensor voltage is more than 4.5 volts, go to step 8 . If TP sensor voltage is 4.5 volts or less, go to next step.
2. While monitoring scan tool display, slowly open and close throttle. If voltage change is smooth, go to next step. If voltage change is not smooth, replace TP sensor. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .
3. Stop moving throttle. While monitoring scan tool display, wiggle TP sensor wiring harness. If voltage changes when wiggling TP sensor harness, repair wiring harness as necessary where wiggling caused problem to appear. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) . If voltage did not change when wiggling TP sensor harness, go to next step.
4. Start engine. While monitoring engine RPM, wiggle TP sensor wiring harness. If engine RPM changed, repair wiring harness as necessary where wiggling caused problem to appear. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) . If engine RPM did not change, go to next step.
5. Condition to set trouble code is not present at this time. THROTTLE POSITION SENSOR VOLTAGE HIGH DTC sets if Powertrain Control Module (PCM) terminal No. 35 is more than 4.5 volts for .7 second. Possible causes are: TP sensor signal is open, TP sensor failure, TP sensor ground circuit open, PCM failure or faulty connections or wiring. Go to next step.
6. Inspect all related wiring and connectors and repair as necessary. If no problems were found with wiring and connectors, problem is not present at this time. Test is complete. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) . If related wiring and connectors were repaired, perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .
7. Using scan tool, read FREEZE FRAME data. Ensure hex code matches DTC on scan tool. Hex code should be 1B. Use this information for additional diagnostics. See «INACTIVE TROUBLE CODE CONDITION»(ref-576-S27765318282000030800000) under SELF-DIAGNOSTICS. Test is complete. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .
8. Disconnect TP sensor connector. Using a voltmeter, check voltage of TP sensor signal circuit at TP sensor connector. See «TP SENSOR WIRE IDENTIFICATION»(ref-576-S27375904852000030800000) table. If voltage is 5.5 volts or less, go to next step. If voltage is more than 5.5 volts, repair short to voltage on TP sensor signal circuit. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .
9. Connect a jumper wire between TP sensor connector signal circuit and sensor ground circuit. See «TP SENSOR WIRE IDENTIFICATION»(ref-576-S27375904852000030800000) table. Using scan tool, read TP sensor voltage. If scan tool displays one volt or more, go to next step. If scan tool displays less than one volt, replace TP sensor. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .
10. Move jumper wire from TP sensor connector ground circuit to engine ground. Using scan tool, read TP sensor voltage. If voltage is one volt or more, go to next step. If voltage is less than one volt, repair open TP sensor ground circuit. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .
11. Turn ignition off. Disconnect Powertrain Control Module (PCM) connector. Using an ohmmeter, check resistance between TP sensor 5-volt supply circuit and TP sensor signal circuit at TP sensor connector. See «TP SENSOR WIRE IDENTIFICATION»(ref-576-S27375904852000030800000) table. If resistance is 5 ohms or more, repair open TP sensor signal circuit. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) . If resistance is less than 5 ohms, replace PCM. Perform «TEST VER-5A: ROAD TEST FOR OBD-II TROUBLE CODES»(ref-576-S36272092702000030800000) .

TP SENSOR WIRE IDENTIFICATION