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Ignition Coil Relay Circuit Troubleshooting

  1. Check the No. 8 (15 A) fuse and No. 9 (15 A) fuse in the under-hood fuse/relay box.

    Are the fuses 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-hood fuse/relay box and the ignition coils.

  2. Remove the relay control module from the under-hood fuse/relay box, and test it (see RELAY CONTROL MODULE TEST ).

    Is the relay OK? 

    YES  - Go to step 3.

    NO  - Replace the relay control module in the under-hood fuse/relay box.

  3. Measure the voltage between the relay control module connector C terminal No. 2 and body ground.
    Fig 1: Identifying Voltage Between Relay Control Module Connector C Terminal No. 2 And Body Ground
    G05484479Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there battery voltage? 

    YES  - Go to step 4.

    NO  - Repair open in the wire between relay control module connector C terminal No. 2 and the main under-hood fuse box.

  4. Check for continuity between the relay control module connector H terminal No. 6 and No. 1 ignition coil 3P connector terminal No. 3.
    Fig 2: Identifying Continuity Between Relay Control Module Connector H And Ignition Coil 3P Connector Terminal
    G05484480Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Go to step 5.

    NO  - Repair open in the wire between the relay control module connector H terminal No. 6 and ignition coil 3P connector terminal No. 3.

  5. Check for continuity between the relay control module connector E terminal No. 5 and body ground.
    Fig 3: Identifying Continuity Between Relay Control Module Connector E Terminal No. 5 And Body Ground
    G05484481Courtesy of AMERICAN HONDA MOTOR CO., INC.

    Is there continuity? 

    YES  - Repair short to body ground in the wire between the relay control module connector E terminal No. 5 and the powertrain control module (PCM) (A6).

    NO  - Go to step 6.

  6. Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see step 2 on HOW TO USE THE HDS (HONDA DIAGNOSTIC SYSTEM) ).
  7. Turn the ignition switch to ON (II).
  8. Make sure the HDS communicates with the vehicle and the PCM. If it doesn't communicate, troubleshoot the DLC circuit (see DLC CIRCUIT TROUBLESHOOTING ).
  9. 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.
  10. Disconnect PCM connector A (49P).
  11. Check for continuity between relay control module connector E terminal No. 5 and PCM connector terminal A6.
    Fig 4: Identifying Continuity Between Relay Control Module Connector E Terminal No. 5 And PCM Connector Terminal A6
    G05484482Courtesy 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 relay control module connector E and the PCM (A6).

    NO  - Repair open in the wire between the relay control module connector E terminal No. 5 and the PCM (A6).