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Ignition Coil Relay Circuit Troubleshooting

  1. Check the No. 8 (15 A) fuse in the auxiliary fuse box.

    Are the fuse OK? 

    YES  -Go to step 2.

    NO  -Replace the fuse.

  2. Remove the ignition coil relay from the relay block and test it (see POWER RELAY TEST ).

    Is the relay OK? 

    YES  -Go to step 3.

    NO  -Replace the ignition coil relay.

  3. Measure the voltage between ignition coil relay 4P socket terminal No. 1 and body ground, then terminal No. 4 and body ground.
    Fig 1: Measuring Voltage Between Ignition Coil Relay 4P Socket Terminal No 1 And Body Ground
    G04545447Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 4.

    NO  -Repair an open in the wire between ignition coil relay 4P socket terminal No. 1 and the auxiliary fuse box or terminal No. 4 and the auxiliary fuse box.

  4. Check for continuity between ignition coil relay 4P socket terminal No. 2 and No. 1 ignition coil 3P connector terminal No. 3.
    Fig 2: Checking Continuity Between Ignition Coil Relay 4P Socket Terminal No 2 And No 1 Ignition Coil 3P Connector Terminal No 3
    G04545448Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 5.

    NO  -Repair an open in the wire between ignition coil relay 4P socket terminal No. 2 and No. 1 ignition coil 3P connector terminal No. 3.

  5. Check for continuity between ignition coil relay 4P socket terminal No. 3 and body ground.
    Fig 3: Checking Continuity Between Ignition Coil Relay 4P Socket Terminal No 3 And Body Ground
    G04545449Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair a short in the wire between ignition coil relay 4P socket terminal No. 3 and PCM.

    NO  -Repair an open in the wire between ignition coil relay 4P socket terminal No. 3 and PCM.