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Ignition Coil Relay Circuit Troubleshooting

  1. Check the No. 2 (15 A) fuse in the driver's under-dash fuse/relay box.

    Is the fuse OK? 

    YES  -Go to step 2.

    NO  -Replace the fuse. If the fuse continues to blow, locate and repair the short in the circuit between the under-dash fuse/relay box and the ignition coils.

  2. Remove the ignition coil relay from the driver's under-dash fuse/relay box, 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
    G06163226Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  -Go to step 4.

    NO  -Replace the driver's under-dash fuse/relay box.

  4. Check for continuity between ignition coil relay 4P socket terminal No. 2 and the 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
    G06163227Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Go to step 5.

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

  5. Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 under GENERAL TROUBLESHOOTING INFORMATION ).
  6. Turn the ignition switch to ON (II).
  7. Make sure the HDS communicates with the vehicle and the powertrain control module (PCM). If it doesn't communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  8. Jump the SCS line with the HDS, then turn the ignition switch to LOCK (0).
    NOTE: This step must be done to protect the PCM from damage.
  9. Disconnect PCM connector E (31P).
  10. 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
    G06163228Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -Repair short in the wire between ignition coil relay 4P socket terminal No. 3 and the PCM (E5).

    NO  -Go to step 11.

  11. Check for continuity between ignition coil relay 4P socket terminal No. 3 and PCM connector terminal E5.
    Fig 4: Checking For Continuity Between Ignition Coil Relay 4P Socket Terminal No. 3 And PCM Connector Terminal E5
    G06163229Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  -The system is OK at this time. Check for loose or poor connections at the ignition coil relay and the PCM (E5).

    NO  -Repair open in the wire between ignition coil relay 4P socket terminal No. 3 and the PCM (E5).