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Crankshaft Position Sensor

  1. Check CKP(+) & CKP(-) Continuity

    Disconnect CKP sensor and PCM connector. Measure resistance of CKP(+) circuit (Dark Blue wire) between PCM connector terminal No. 21 and CKP sensor harness connector. Record reading. Measure resistance of CKP(-) circuit (Gray wire) between PCM connector terminal No. 22 and CKP sensor harness connector. Record reading. If either resistance reading is more than 5 ohms, repair open circuit. See WIRING DIAGRAMS article. If resistance readings are 5 ohms or less, go to next step.

  2. Check For CKP(+) Bias Voltage Fault

    Reconnect PCM connector. Measure voltage of CKP(+) circuit (Dark Blue wire) between PCM connector terminal No. 21 and CKP sensor harness connector. If voltage is more than one volt, but less than 2 volts, go to next step. If voltage is one volt or less, or 2 volts or more, a bias fault is present. Go to next step.

  3. Check For CKP(-) Bias Voltage Fault

    Measure voltage of CKP(-) circuit (Gray wire) between PCM connector terminal No. 22 and CKP sensor harness connector. If voltage is one to 2 volts, turn ignition off. Go to step  7 . If voltage is not one to 2 volts, a bias fault is present. Go to next step.

  4. Determine If Bias High Or Bias Low Fault

    If voltage reading in step  3 was less than one volt, a bias low fault is present. Go to step  6 . If voltage reading in step  3 was one volt or more, a bias high fault is present. Go to step  6 .

  5. Check CKP(-) Circuit For Short To Ground In Harness

    Disconnect PCM connector. Measure resistance of CKP(-) circuit (Gray wire) between PCM connector terminal No. 22 and battery negative terminal. If resistance is more than 10,000 ohms, replace faulty PCM. If resistance is 10,000 ohms or less, repair short circuit. See WIRING DIAGRAMS article.

  6. Check CKP(-) Circuit For Short To Power In Harness

    Disconnect PCM connector. With KOEO, measure voltage of CKP(-) circuit (Gray wire) between PCM connector terminal No. 22 and battery negative terminal. If voltage is less than 0.5 volt, replace faulty PCM. If voltage is 0.5 volt or more, repair short circuit. See WIRING DIAGRAMS article.

  7. Check CKP Sensor Amplitude At PCM

    Reconnect CKP sensor. Disconnect PCM connector. While cranking engine, measure AC voltage between CKP(+) circuit (Dark Blue wire) and CKP(-) circuit (Gray wire) at PCM connector. Turn ignition off. If (settled) AC voltage is more than 0.4 volt, CKP circuit is okay. Go to step  13 . If (settled) AC voltage is 0.4 volt or less, an amplitude fault is present. Go to next step.

  8. Check CKP Circuit Resistance For Amplitude Fault

    Measure resistance between CKP(+) circuit (Dark Blue wire) and CKP(-) circuit (Gray Wire) at PCM connector. If resistance is 300-800 ohms, go to step  12 . If resistance is not 300-800 ohms, go to next step.

  9. Determine If Resistance High Or Resistance Low Fault

    If resistance from step  8 is less than 300 ohms, a low resistance fault is present. Go to step  10 . If resistance from step  8 is not less than 300 ohms, replace faulty CKP sensor.

  10. Check CKP(+) For Short To CKP(-)

    Disconnect CKP sensor. Measure resistance between CKP(+) circuit and CKP(-) circuit at CKP sensor connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, replace faulty CKP sensor.

  11. Check CKP Sensor & Pulse Wheel

    Visually check pulse wheel and CKP sensor for damage. If components are okay, replace faulty CKP sensor. Test is complete. If either component is damaged, repair or replace components as necessary.

  12. Check For Open Or Short In PCM

    Disconnect CKP sensor. Connect PCM connector. Measure resistance between CKP(+) circuit (Dark Blue wire) and CKP(-) circuit (Gray wire) at CKP sensor harness connector. If resistance is 16,000-24,000 ohms, go to step  14 . If resistance is not 16,000-24,000 ohms, replace faulty PCM.

  13. Check CKP(+) Circuit For Short To CKP(-) Circuit In Harness

    Disconnect CKP sensor. Measure resistance between CKP(+) circuit (Dark Blue wire) and CKP(-) circuit (Gray wire) at PCM connector. If resistance is more than 1000 ohms, replace faulty CKP sensor. If resistance is 1000 ohms or less, repair short circuit. See WIRING DIAGRAMS article.

  14. Determine If Bias Voltage High Or Bias Voltage Low Fault

    If bias voltage reading in step  2 is less than one volt, a low bias voltage fault is present. Go to next step. If bias voltage reading in step  2 is one volt or more, a high bias voltage fault is present. Go to step  16 .

  15. Check CKP(+) Circuit For Short To Ground In Harness

    Disconnect PCM connector. Measure resistance between CKP sensor harness connector CKP(+) circuit (Dark Blue wire) and battery negative terminal. If resistance is more than 10,000 ohms, replace faulty PCM. If resistance is 10,000 ohms or less, repair short circuit. See WIRING DIAGRAMS article.

  16. Check CKP(+) Circuit For Short To Power In Harness

    Disconnect PCM connector. With KOEO, measure voltage between CKP sensor harness connector CKP(+) circuit (Dark Blue wire) and battery negative terminal. If voltage is less than 0.5 volt, replace faulty PCM. If voltage is 0.5 volt or more, repair short circuit. See WIRING DIAGRAMS article.
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