Circuit/System Testing
- Ignition OFF, disconnect the EC ignition relay.
- Ignition ON, test for battery voltage between the relay switch battery voltage circuit terminal 30 and ground.
- If less than B+, repair the B+ circuit for a short to ground or an open/high resistance.
- Test for battery voltage between the relay coil B+ voltage circuit terminal 86 and ground.
- If less than B+, repair the B+ voltage circuit for a short to ground or an open/high resistance. Replace the fuse if necessary.
- Ignition OFF, connect a test lamp between the relay coil control circuit terminal 85 and the relay coil B+ circuit terminal 86.
- Ignition ON, command the EC ignition relay ON with a scan tool. The test lamp should turn ON for about 3-5 seconds and then turn OFF.
- If the test lamp is always ON, test the relay coil control circuit for a short to ground. If the circuit tests normal, replace the ECM.
- If the test lamp is always OFF, test the relay coil control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the ECM.
- Connect a 15A fused jumper wire between the relay switch supply circuit terminal 87 and the relay switch B+ circuit terminal 30.
- Attempt to start the engine. The engine should start.
- If the engine does not start, test the relay switch B+ circuit terminal 30 between the EC ignition relay and the ECM for a short to ground or for an open/high resistance. If the circuit tests normal, replace the ECM.
- If all circuits test normal, test or replace the EC ignition relay.
IMPORTANT:
The ignition 1 voltage circuit is between the EC ignition relay and the ECM. The ignition 1 voltage is a feedback circuit.