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DTC P0320: No Crank Reference Signal At Pcm: Testing

  1. Turn ignition on, with engine off. Using scan tool, read current CKP count and attempt to start engine. If current CKP count changes while attempting to start engine, go to next step. If current CKP count does not change while attempting to start engine, go to step  4 .
  2. Turn ignition off. Visually inspect related connectors and wiring harness. Repair connectors and wiring harness as necessary. If connectors and wiring harness are okay, go to next step.
  3. Start engine and allow it to idle. Wiggle wiring harness from CKP sensor to PCM. PCM is located in engine compartment on left front fender, near radiator support. CKP sensor is mounted to left side of transmission bellhousing. CKP sensor connector is located on top of intake manifold, near firewall. If engine stalls while wiggling wiring harness, repair wiring harness as necessary where wiggling caused engine to stall. If engine does not stall while wiggling wiring harness, test is complete.
  4. Turn engine off. Disconnect CKP sensor connector. Inspect connector for damaged pins, corrosion and loose terminals. Repair connector as necessary. If connector is okay, go to next step.
  5. Ensure ignition is off and CKP sensor connector is still disconnected. Turn ignition on, with engine off. Measure voltage between ground and Orange wire at CKP sensor connector. If voltage is more than 4.5 volts, go to next step. If voltage is 4.5 volts or less, go to step  11 .
  6. Measure resistance between ground and Brown/Yellow wire at CKP sensor connector. If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Brown/Yellow wire between ground and CKP sensor connector.
  7. Ensure ignition is off. Ensure CKP sensor connector is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment on left front fender, near radiator support. Visually inspect connectors for corroded, damaged, pushed-out or miswired terminals. Repair connectors as necessary. If connectors are okay, go to next step.
  8. Ensure ignition is off. Ensure CKP sensor and PCM connectors are still disconnected. Measure resistance of Gray/Black wire between CKP sensor connector and terminal No. 8 at PCM C1 connector. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Gray/Black wire.
  9. Measure resistance between ground and terminal No. 8 (Gray/Black wire) at PCM C1 connector. See Figure . If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Gray/Black wire.
  10. Turn ignition off. Remove crankshaft position sensor. Inspect notches on flywheel/drive plate for damage or debris. On 2.5L, flywheel/drive plate contains 2 sets of notches which contain 4 slots each on outer edge of flywheel/drive plate. On 4.0L, flywheel/drive plate contains 3 sets of notches which contain 4 slots in each set. On all models, check slotted areas for damage or any foreign debris. If slotted areas on flywheel/drive plate are okay and no debris exists, replace CKP sensor. If slotted areas on flywheel/drive plate are damaged or debris exists, repair or replace flywheel/drive plate as necessary.
  11. Ensure ignition is off. Ensure CKP sensor is still disconnected. Disconnect PCM connectors. PCM is located in engine compartment on left front fender, near radiator support. Visually inspect PCM connectors for corroded, damaged, pushed-out or miswired terminals. Repair connectors as necessary. If connectors are okay, go to next step.
  12. Measure resistance of Orange wire between CKP sensor connector and terminal No. 17 at PCM C1 connector. See Figure . If resistance is less than 5 ohms, go to next step. If resistance is 5 ohms or more, repair open in Orange wire between PCM and CKP sensor.
  13. Measure resistance between ground and terminal No. 17 (Orange wire) at PCM C1 connector. If resistance is 5 ohms or more, go to next step. If resistance is less than 5 ohms, repair short to ground in Orange wire.
  14. At this time, PCM is assumed to be defective. Replace PCM.
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