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Code 4 - Crank Angle 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 4. If LED is flashing Code 4, go to next step. If LED is not flashing Code 4, problem is intermittent. Check connectors at distributor and related circuits.
  2. Turn ignition off. Disconnect 4-wire TDC/CRANK sensor connector nearest sensor. Measure resistance across terminals "C" and "D" at sensor. See Fig 1 . If reading is not 700-1000 ohms, replace pulse generator assembly. If reading is within specification, proceed to next step.
  3. Check continuity between ground and sensor terminals "C" and "D" individually. If continuity exists on either terminal, sensor is shorted to ground. Replace pulse generator assembly. If no continuity exists, go to next step.
  4. Reconnect sensor connector. Connect appropriate ECU Test Harness (07999-PD6000A or 07LAJ-PT3010A ) to main harness side only. See Figure and Figure . Check resistance between connector terminals B10 and B12 (B15 and B16 on 2.1L). See Figure and Figure . Resistance should be 700-1000 ohms.
  5. If resistance is not within specification, repair open in Blue/Yellow and/or Blue/Green wire. If resistance is within specification, check for continuity from terminal B10 (B15 on 2.1L) to ground.
  6. If continuity exists, repair short in Blue/Green wire between ECU terminal B10 (B15 on 2.1L) and distributor. If continuity does not exist, substitute a known good ECU, and recheck. If condition is corrected, replace original ECU.
    Fig 1: TDC/CRANK Sensor Connector Terminal ID
    G117903Courtesy of AMERICAN HONDA MOTOR CO., INC.