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Diagnostic Procedures

NOTE: If any other DTCs are set, diagnose those DTCs first.
  1. Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK  under SELF-DIAGNOSTIC SYSTEM. After performing powertrain diagnostic system check, go to next step.
  2. Turn ignition on, engine off. Using scan tool, observe TP sensor angle parameter while slowly opening throttle to WOT. Parameter should be at zero percent at closed throttle and 98 percent at WOT. If TP angle increases steadily and evenly from closed throttle value to more than wide open throttle value, go to next step. If TP angle does not increase steadily and evenly from closed throttle to more than WOT throttle value, go to step  4.
  3. Observe FREEZE FRAME/FAILURE RECORDS for this DTC. Turn ignition off for 30 seconds. Operate vehicle within code enable criteria or as close to FREEZE FRAME/FAILURE RECORDS as possible. If DTC fails this ignition cycle, go to next step. If DTC does not fail this ignition cycle, see DIAGNOSTIC AIDS .
  4. Turn ignition off. Disconnect TP sensor connector. See Figure or Figure . Turn ignition on, engine off. Using scan tool, observe TP sensor voltage parameter. If scan tool indicates TP sensor voltage is zero, go to next step. If scan tool does not indicate TP sensor voltage is zero, go to step  6.
  5. Turn ignition off. Connect a fused jumper wire (3-amp) between TP sensor connector terminals "B" (Dark Blue wire) and "C" (Gray wire). See Figure. Turn ignition on, engine off. Using scan tool, observe TP sensor voltage parameter. If scan tool indicates TP sensor voltage is 5 volts, go to step  9. If scan tool does not indicate TP sensor voltage is 5 volts, go to step  7.
  6. Check Dark Blue wire between TP sensor and PCM for short to voltage. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to step  12.
  7. Check Gray wire between TP sensor and PCM for open or high resistance. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to next step.
  8. Check Dark Blue wire between TP sensor and PCM for open or high resistance. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to step  11.
  9. Check Black wire between TP sensor and PCM for open or high resistance. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to next step.
  10. Check Gray wire between TP sensor and PCM for high resistance. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to next step.
  11. Check TP sensor connector for poor connections. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to step  13.
  12. Check PCM connectors for poor connections. If problem was found, repair as necessary. After repairs, go to step  15. If problem was not found, go to step  14.
  13. Replace TP sensor. After repairs, go to step  15.
  14. Replace PCM. Program replacement PCM. See POWERTRAIN CONTROL MODULE  under PROGRAMMING. After repairs, go to next step.
  15. Using scan tool, clear DTCs. Turn ignition off for 30 seconds. Start engine. Operate vehicle within code enable criteria. If DTC runs and passes, go to next step. If DTC does not run and pass, go to step  2.
  16. Using scan tool, observe stored information. If scan tool displays any DTCs that have not been diagnosed, see DIAGNOSTIC TROUBLE CODE DEFINITIONS . If scan tool does not display any DTCs, system is okay.
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