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Home >> Honda >> 1987 >> Prelude Base, Standard >> Repair and Diagnosis >> Engine Performance >> System >> PGM-FI Electronic Control System >> Testing >> Code 9, CRK/CYL Sensor
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Code 9, CRK/CYL Sensor

  1. Turn ignition off. Remove No. 11 fuse in the under-hood relay box for 10 seconds to reset ECU. Start engine and observe PGM-FI warning light. If light is off, problem is intermittent. Test drive and check again.
  2. If light is on, turn ignition off. Disconnect 4-wire sensor connector near distributor. Measure resistance between White and Orange wire terminals at sensor. If reading is not 650-850, replace sensor. If reading is within specification, proceed to next step.
  3. Check continuity between ground and White wire terminal. Check continuity between ground and Orange wire terminal. If continuity exists, sensor is shorted to ground. Replace sensor. If no continuity exists, proceed to next step.
  4. Reconnect sensor connector. Attach system checker harness to main wire harness only, not to ECU. Check resistance between connector terminals C1 and C2. Resistance should be 650-850 ohms.
  5. If resistance not within specification, repair open in Orange and/or White wire. If resistance is within specification, substitute a known good ECU. If condition is rectified, replace original ECU.
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