When main relay (Engine control relay) is NOT operated although IG KEY "ON" signal circuit and main relay circuit are normal. Inspect the ECM ground.
IG KEY "OFF" , ENGINE "OFF"
Disconnect ECM connector.
Measure resistance between ground terminals of ECM harness connector and chassis ground.
■ Specification : Below 0.2 Ω
Symptom | Inspection procedure | |
Case1 | ● ECM grounds are normal. | ● When Main relay is not operated although IG KEY "ON" signal circuit, main relay circuit and ground circuit are normal. ● Replace ECM |
Case2 | ● There is discontinuity or high resistance between ground terminals of ECM harness connector and chassis ground. | ● Repair chassis ground point. ● Repair open in ground circuit. |