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Test Kn: Throttle Position Switch: Testing

    NOTE: For additional testing information, see DIAGNOSTIC AIDS .

  1. 1) DTC P1705: Check For Other DTCs
    Connect scan tool to DLC. Perform QUICK TEST  and check for DTC P0120. If DTC P0120 is present along with DTC P1705, go to TEST DH  , step  1). If DTC P0120 is not present, go to next step.

  2. 2) Check TP Switch Circuits For Frayed Wires Or Corrosion On Connectors

    Turn ignition off. Visually inspect pins on harness connector at TP switch for corrosion and harness wires between TP switch and TCM for insulation fraying and corrosion. Repair as necessary. If harness connector pins and insulation is okay, go to next step.

  3. 3) Check TP SIG Circuit Between PCM & TCM

    Ensure ignition is off. Disconnect TCM harness connector C277b. Turn ignition on. Using DVOM, measure voltage between TCM harness connector C277b terminal No. 17 (Red/Green wire) and No. 18 (Black/Yellow wire) while slowly depressing accelerator pedal. See Figure. If voltage is less than one volt at closed throttle and 4-5 volts with accelerator pedal at Wide Open Throttle (WOT), leave ignition on and go to step  8). If voltage is not less than one volt at closed throttle or 4-5 volts with accelerator pedal at WOT, go to next step.

  4. 4) Check SIG RTN Circuit Between PCM & TCM For Open

    Turn ignition off. Disconnect PCM harness connector. Inspect connector for damaged pins and repair if necessary. Using DVOM, measure resistance of SIG RTN circuit (Black/Yellow wire) between PCM harness connector terminal No. 58 and TCM harness connector C277b terminal No. 18. See Figure and Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in SIG RTN circuit. See WIRING DIAGRAMS article.

  5. 5) Check TP SIG Circuit For Open In Harness

    Using DVOM, measure resistance of TP SIG circuit (Red/Green wire) between PCM harness connector terminal No. 33 and TCM harness connector C277b terminal No. 17. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in TP SIG circuit. See WIRING DIAGRAMS article.

  6. 6) Check TP SIG Circuit For Short To VREF Or VPWR

    Using DVOM, measure resistance between TP SIG circuit and VPWR, and VREF circuits at PCM harness connector terminals. See PCM TERMINAL CIRCUIT IDENTIFICATION  table. See Figure. If all resistances are more than 10 k/ohms, go to next step. If any resistance is 10 k/ohms or less, repair short between circuits.

  7. 7) Check TP SIG Circuit For Short To PWR GND Or SIG RTN

    Using DVOM, measure resistance between TP SIG and GND, and SIG RTN circuits at PCM harness connector. See PCM TERMINAL CIRCUIT IDENTIFICATION  table. See Figure. If all resistances are more than 10 k/ohms, replace PCM. If any resistance is 10 k/ohms or less, repair short between circuits. See WIRING DIAGRAMS article.

  8. 8) Check IDLE Circuit

    Turn ignition off. Disconnect TCM harness connector C277a. Turn ignition on. Using DVOM, measure voltage between chassis ground and IDLE circuit at TCM harness connector C277a terminal No. 16 (Brown/Yellow wire) while slowly depressing accelerator pedal. See Figure. If voltage is more than 10 volts at closed throttle and less than one volt with accelerator pedal fully depressed, leave ignition on and go to step  11). If voltage is 10 volts or less at closed throttle or one volt or more with accelerator pedal fully depressed, go to next step.

  9. 9) Check TP Switch IGN Circuit For Voltage

    Turn ignition off. Disconnect TP switch harness connector. Turn ignition on. Using DVOM, measure voltage between chassis ground and IGN circuit at TP switch harness connector terminal No. 2 (Blue/Yellow wire). See Figure. If voltage is more than 10 volts, go to next step. If voltage 10 volts or less, repair open IGN circuit. See WIRING DIAGRAMS article.

  10. 10) Check TP Switch IDLE Circuit

    Turn ignition off. Using DVOM, measure resistance between TP switch component connector terminals No. 3 (IDLE circuit) and No. 2 (IGN circuit) while slowly depressing accelerator pedal. If resistance is less than 5 ohms at closed throttle and more than 10 k/ohms with accelerator pedal fully depressed, repair open in IDLE circuit. If resistance is 5 ohms or more at closed throttle or 10 k/ohms or less with accelerator pedal fully depressed, replace TP switch.

  11. 11) Check WOT Circuit

    Using DVOM, measure voltage between chassis ground and TCM harness connector C277a terminal No. 17 (WOT circuit) while slowly depressing accelerator pedal. See Figure. If voltage is less than one volt at closed throttle and more then 10 volts with accelerator pedal fully depressed, replace TCM. If voltage is one volt or more at closed throttle or 10 volts or less with accelerator pedal fully depressed, go to next step.

  12. 12) Check TP Switch WOT Circuit

    Turn ignition off. Using DVOM, measure resistance between TP switch component connector terminals No. 1 (WOT circuit) and No. 2 (IGN circuit) while slowly depressing accelerator pedal. See Figure. If resistance is more than 10 k/ohms at closed throttle and less then 5 ohms with accelerator pedal fully depressed, repair open in WOT circuit. See WIRING DIAGRAMS article. If resistance is 10 k/ohms or less at closed throttle or 5 ohms or more with accelerator pedal fully depressed, replace TP switch.
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