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Crankshaft Position Sensor

  1. Check CKP(+) & CKP(-) Continuity -  Disconnect Crankshaft Position (CKP) sensor 2-pin harness connector and PCM 104-pin harness connector. Measure resistance of CKP(+) circuit (Dark Blue wire) between PCM 104-pin harness connector terminal No. 21 and CKP sensor harness connector. Record reading. Measure resistance of CKP(-) circuit (Gray wire) between PCM 104-pin harness connector terminal No. 22 and CKP sensor harness connector. Record reading. If resistance readings are 5 ohms or less, go to next step. If either resistance reading is more than 5 ohms, repair open circuit. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS.
  2. Check For CKP(+) Bias Voltage Fault -  Reconnect PCM 104-pin harness connector. Measure voltage of CKP(+) circuit (Dark Blue wire) between PCM 104-pin harness connector terminal No. 21 and CKP sensor harness connector. If voltage reading is more than one volt, but less than 2 volts, go to next step. If voltage reading 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 104-pin harness connector terminal No. 22 and CKP sensor harness connector. If voltage reading is one to 2 volts, turn ignition off. Go to step  7 . If voltage reading 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 not less than one volt, a bias high fault is present. Go to step  6 .
  5. Check CKP(-) Circuit For Short To Ground In Harness -  Disconnect PCM 104-pin harness connector. Measure resistance of CKP(-) circuit (Gray wire) between PCM 104-pin harness connector terminal No. 22 and negative battery terminal. If resistance reading is more than 10,000 ohms, replace faulty PCM. If resistance reading is 10,000 ohms or less, repair short circuit in Gray wire between PCM 104-pin harness connector terminal No. 22 and CKP sensor harness connector. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS.
  6. Check CKP(-) Circuit For Short To Power In Harness -  Disconnect PCM 104-pin harness connector. With KOEO, measure voltage of CKP(-) circuit (Gray wire) between PCM 104-pin harness connector terminal No. 22 and negative battery terminal. If voltage reading is less than 0.5 volt, replace faulty PCM. If voltage reading is 0.5 volt or more, repair short circuit in Gray wire between PCM 104-pin harness connector terminal No. 22 and CKP sensor harness connector.
  7. Check CKP Sensor Amplitude At PCM -  Reconnect CKP sensor harness connector. Disconnect PCM 104-pin harness connector. While cranking engine, measure AC voltage between CKP(+) circuit terminal No. 21 (Dark Blue wire) and CKP(-) circuit terminal No. 22 (Gray wire) at PCM 104-pin harness connector. Turn ignition off. If (settled) AC voltage reading is more than 0.4 volt, CKP circuit is okay. Go to step  13 . If (settled) AC voltage reading 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 terminal No. 21 (Dark Blue wire) and CKP(-) circuit terminal No. 22 (Gray wire) at PCM 104-pin harness connector. If resistance reading is 300-800 ohms, go to step  12 . If resistance reading is not 300-800 ohms, go to next step.
  9. Determine If Resistance High Or Resistance Low Fault -  If resistance reading from step  8 is less than 300 ohms, a low resistance fault is present. Go to next step. If resistance reading from step  8 is not less than 300 ohms, replace faulty CKP sensor.
  10. Check CKP(+) For Short To CKP(-) -  Disconnect CKP sensor harness connector. Measure resistance between CKP(+) circuit and CKP(-) circuit at CKP sensor harness 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 both 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 harness connector. Connect PCM 104-pin harness connector. Measure resistance between CKP(+) circuit (Dark Blue wire) and CKP(-) circuit (Gray wire) at CKP sensor harness connector. If resistance reading is 16,000-24,000 ohms, go to step  14 . If resistance reading is not 16,000-24,000 ohms, replace faulty PCM.
  13. Check CKP(+) Circuit For Short To CKP(-) Circuit In Harness -  Disconnect CKP sensor harness connector. Measure resistance between CKP(+) circuit terminal No. 21 (Dark Blue wire) and CKP(-) circuit terminal No. 22 (Gray wire) at PCM 104-pin harness connector. If resistance reading is more than 1000 ohms, replace faulty CKP sensor. If resistance reading is 1000 ohms or less, repair short circuit. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS.
  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 104-pin harness connector. Measure resistance of CKP(+) circuit (Dark Blue wire) between PCM 104-pin harness connector terminal No. 21 and negative battery terminal. If resistance reading is more than 10,000 ohms, replace faulty PCM. If resistance reading is 10,000 ohms or less, repair short circuit in Dark Blue wire between PCM 104-pin harness connector terminal No. 21 and CKP sensor harness connector.
  16. Check CKP(+) Circuit For Short To Power In Harness -  Disconnect PCM 104-pin harness connector. With KOEO, measure voltage between of CKP(+) circuit (Dark Blue wire) between PCM 104-pin harness connector terminal No. 21 and negative battery terminal. If voltage reading is less than 0.5 volt, replace faulty PCM. If voltage reading is 0.5 volt or more, repair short circuit in Dark Blue wire between PCM 104-pin harness connector terminal No. 21 and CKP sensor harness connector. See appropriate WIRING DIAGRAM under ENGINE PERFORMANCE in SYSTEM WIRING DIAGRAMS.
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