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Code 9 - CYL Sensor

  1. Turn ignition off. Remove BACK-UP fuse for 10 seconds to reset ECU. Start engine. Verify if CHECK ENGINE light is flashing Code 9. If Code 9 is present, go to next step. If Code 9 is not present, problem is intermittent. Check connectors at distributor and related circuits.
  2. Turn ignition off. Disconnect 8-wire sensor connector near distributor. Measure resistance between terminals "D" and "H" at sensor harness connector. See Figure . If reading is not 260-500 ohms, replace distributor assembly. If reading is within specification, proceed to next step.
  3. Check continuity between ground and terminals "D" and "H" individually. If continuity exists at either terminal, replace distributor assembly. If no continuity exists, proceed to next step.
  4. Reconnect sensor connector. Attach ECU Test Harness (07LAJ-PT3010A ) to main wire harness side only. See Figure . Check resistance between connector terminals B11 and B12. See Figure . Resistance should be 260-500 ohms. If resistance is not as specified, repair open in Orange and/or White wires.
  5. If resistance is within specification, check continuity between terminal B11 and ground. If continuity is present, repair short in Orange wire between ECU terminal B11 and distributor connector.
  6. If continuity is not present, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU.
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