Ignition System: Testing and Inspection
Ignition Coil Relay Circuit Troubleshooting1. Check the No. 2 (15 A) fuse in the under-dash fuse/relay 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 under-dash fuse/relay box and ignition coils.
2. Remove the ignition coil relay from the under-dash fuse/relay box, and test it.
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.
Is there battery voltage?
YES - Go to step 4.
NO - Replace the 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.
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. Check for continuity between ignition coil relay 4P socket terminal No. 3 and body ground.
Is there continuity?
YES - Repair short in the wire between ignition coil relay 4P socket terminal No. 3 and the engine control module (ECM)/powertrain control module (PCM) (A5).
NO - Go to step 6.
6. Check for continuity between ignition coil relay 4P socket terminal No. 3 and ECM/PCM connector terminal A5.
Is there continuity?
YES - The system is OK at this time. Check for loose or poor connections at the ignition coil relay and the ECM/PCM (A5).
NO - Repair open in the wire between ignition coil relay 4P socket terminal No. 3 and the ECM/PCM (A5).