Ignition Coil Relay Circuit Troubleshooting

Check the No. 8 (15 A) fuse in the auxiliary fuse box.
Is the fuse OK?

YES - Reinstall the fuse, then go to step 2.

NO - Replace the fuse. If the fuse continues to blow, locate and repair the short in the circuit between the ignition coil relay and the ignition coils.
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.
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, Then Terminal No. 4 And Body Ground
Courtesy 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.
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 For Continuity Between Ignition Coil Relay 4P Socket Terminal No. 2 And No. 1 Ignition Coil 3P Connector Terminal No. 3
Courtesy 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.
Check for continuity between each ignition coil 3P connector terminal No. 2 and body ground.

Fig 3: Checking Continuity Between Each Ignition Coil 3P Connector Terminal No. 2 And Body Ground
Courtesy of AMERICAN HONDA MOTOR CO., INC.
Connect the Honda Diagnostic System (HDS) to the data link connector (DLC) (see How to Use The HDS (Honda Diagnostic System) in GENERAL TROUBLESHOOTING INFORMATION ). Turn the ignition switch ON (II), and jump the SCS line with the HDS, then turn the ignition switch OFF.
NOTE: This step must be done to protect the powertrain control module (PCM) from damage.
Disconnect PCM connector A (44P).
Check for continuity between ignition coil relay 4P socket terminal No. 3 and body ground

Fig 4: Checking Continuity Between Ignition Coil Relay 4P Socket Terminal No. 3 And Body Ground
Courtesy 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 the PCM (A6).

NO - Go to step 9.
Check for continuity between ignition coil relay 4P socket terminal No. 3 and PCM connector terminal A6.

Fig 5: Checking Continuity Between Ignition Coil Relay 4P Socket Terminal No. 3 And PCM Connector Terminal A6
Courtesy 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 (A6).

NO - Repair an open in the wire between ignition coil relay 4P socket terminal No. 3 and the PCM (A6).