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Code 4: CRK/CYL Sensor: Coupe

  1. Turn ignition switch off and disconnect alternator sense fuse in under hood relay box for 10 seconds to reset ECU. Start engine and check for PGM-FI warning light on or off. If light is off, test drive and check again.
  2. If light is on, turn engine off. Disconnect sensor connector nearest the sensor. Measure resistance between sensor connector and sensor, Blue/Yellow terminal and Blue/Green terminal, with an ohmmeter. If ohm reading is not 500-1000 ohms, replace sensor. If ohm reading is within specifications, go to next step.
  3. Check continuity between ground and Blue/Yellow terminal. Check continuity between ground and Blue/Green terminal. If continuity exists, replace sensor. If no continuity exists, go to next step.
  4. Reconnect sensor connector. Attach system checker harness to right side wire harness only, not to ECU. Using an ohmmeter, check resistance between connector terminal No. B19 and No. B20. Resistance should be 500-1000 ohms.
  5. If resistance not within specifications, repair open in Blue/Yellow and/or Blue/Green wire. If resistance is within specifications, connect a known good ECU and recheck. Replace ECU if original is defective.
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