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Code 9 - CYL Sensor

  1. Turn ignition off. Remove CLOCK fuse for 10 seconds to reset ECU. Start engine. Verify if CHECK ENGINE light is on and if LED is flashing Code 9. If LED is flashing Code 9, go to next step. If LED is not flashing Code 9, problem is intermittent. Check connectors at distributor and related circuits.
  2. Turn ignition off. Disconnect 2-wire sensor connector. Measure resistance across sensor terminals. If reading is not 700-1000 ohms, replace CYL sensor assembly. If reading is within specification, proceed to next step.
  3. Check continuity between ground and each sensor terminal. If continuity exists, replace CYL sensor 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. Check resistance between connector terminals C1 and C2 (B11 and B12 on 2.1L). Resistance should be 700-1000 ohms.
  5. If resistance is not within specification, repair open or short in Orange and/or White wires. If resistance is within specification, check continuity between terminal C1 (B11 on 2.1L) and ground. If continuity is not present, repair open in Orange wire between ECU terminal C1 (B11 on 2.1L) and CYL sensor connector. If resistance is within specification, substitute a known good ECU, and retest. If condition is corrected, replace original ECU.
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