DTC P0123: THROTTLE POSITION SENSOR VOLTAGE HIGH Dodge Ram Wagon B1500

Note. For connector terminal identification, see CONNECTOR IDENTIFICATION . For circuit identification and wiring diagram, see RAM VAN & RAM WAGON wiring diagram in WIRING DIAGRAMS article.

Note. DTC P0123: THROTTLE POSITION SENSOR VOLTAGE HIGH is monitored with ignition on and battery voltage more than 10.4 volts. DTC may be stored in Powertrain Control Module (PCM) when PCM senses Throttle Position (TP) sensor voltage is 4.9 volts for 3.2 seconds. Possible causes are: defective TP sensor, defective PCM, defective connectors or defective wiring.

1. Turn ignition on, with engine off. Using scan tool, read TP sensor voltage. If voltage is more than 4.5 volts, go to next step. If voltage is 4.5 volts or less, go to step 7).
2. Turn ignition off. Disconnect TP sensor connector. (Схема №19) Clean and/or repair connector as necessary. Connect a jumper wire between TP sensor connector, signal circuit (Orange/Dark Blue wire) and sensor ground circuit (Black/Light Blue wire). Using scan tool, read TP sensor voltage. If voltage is less than one volt, replace TP sensor. Perform TEST VER-5A. If voltage is more than one volt, go to next step.
3. Turn ignition off. Ensure TP sensor connector is still disconnected. Clean and/or repair connector as necessary. Connect a jumper wire between ground and TP sensor connector, signal circuit (Orange/Dark Blue wire). Using scan tool, read TP sensor voltage. If voltage is less than one volt, repair open in signal circuit. Perform TEST VER-5A. If voltage is more than one volt, go to next step.
4. Turn ignition off. Ensure TP sensor connector is still disconnected. Clean and/or repair connector as necessary. Turn ignition on, with engine off. Using a voltmeter, check voltage on TP sensor connector, signal circuit (Orange/Dark Blue wire). If voltage is more than 5.5 volts, repair signal circuit for short to voltage. Perform TEST VER-5A. If voltage is 5.5 volts or less, go to next step.
5. Turn ignition off. Ensure TP sensor connector is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment. See PCM LOCATION table under SYSTEM DIAGNOSTICS. Clean and/or repair connectors as necessary. Using an ohmmeter, check resistance of sensor signal circuit (Orange/Dark Blue wire) between TP sensor and PCM. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open signal circuit. Perform TEST VER-5A.
6. At this time, PCM is assumed to be defective. Replace PCM. Perform TEST VER-5A.
7. Start engine and allow it to idle. Wiggle TP sensor connector and wiring harness while monitoring engine RPM. If an RPM change occurs while wiggling connector and wiring harness, repair connector or wiring harness that caused RPM to change. Perform TEST VER-5A. If no RPM change occurs, go to next step. NOTE: Throttle linkage must be moved very slowly while looking for a smooth change in voltage in this step.
8. Ensure ignition is on, with engine off. Slowly open and close throttle plate while monitoring TP sensor voltage. If voltage change is smooth, go to next step. If voltage change is erratic, replace TP sensor. Perform TEST VER-5A.
9. Turn ignition on, with engine off. Wiggle TP sensor connector and wiring harness while monitoring TP sensor voltage. If voltage changes while wiggling connectors and wiring harness, repair connectors and wiring harness that caused voltage to change. Perform TEST VER-5A. If voltage does not change, go to next step.
10. Turn ignition off. Visually inspect related connectors and wiring harness for damage. Repair connectors and wiring harness as necessary. Perform TEST VER-5A. If connectors and wiring harness are okay, go to next step.
11. Ensure ignition is on, with engine off. Using scan tool, read and record FREEZE FRAME data. Ensure CAUSED BY DTC matches DTC on DTC screen. If DTC matches, road test vehicle under conditions in FREEZE FRAME data. Using scan tool, read DTCs. If DTC P0123: THROTTLE POSITION SENSOR VOLTAGE HIGH returns, visually inspect related connectors and wiring harness for damage. Repair connectors and wiring harness as necessary. Perform TEST VER-5A. If DTC P0123: THROTTLE POSITION SENSOR VOLTAGE HIGH does not return, see «INACTIVE DTC CONDITION»(ref-139160-S32382818132002042600000). Test is complete.