Circuit/System Testing
- Ignition OFF, disconnect the X1 harness connector at the K20 ECM.
- Ignition ON, the MIL should not illuminate.
- If the MIL illuminates, test the MIL control circuit terminal 68-X1 for a short to ground. If the circuit tests normal, replace the P16 instrument panel cluster.
- Connect a 3 A fused jumper wire between the MIL control circuit terminal 68-X1 and ground. The MIL should illuminate.
- If the MIL illuminates, replace the ECM.
- If the MIL does not illuminate, test the MIL control circuit for a short to voltage or an open/high resistance. If the MIL control circuit tests normal, test the instrument cluster ignition voltage circuit for a short to ground or an open/high resistance. If the circuits test normal, replace the instrument panel cluster/bulb.