Ignition "OFF" & Engine "OFF".

Disconnect Main relay.

Measure resistance between terminal 2 and 4 of main relay (Component side).

Specification : 70 ~ 90Ω (20°C)

Is the measured resistance within specifications ?

YES

▶ Go to "Check Main relay operation " as below.

NO

▶ Substitute with a known-good Main relay and check for proper operation.

If the problem is corrected, replace main relay and then go to "Verification of Vehicle Repair" procedure.

Ignition "OFF" & Engine "OFF".

Connect Main relay and Disconnect ECM connector.

Connect volt meter or test lamp with terminal 4 and 5 of ECM harness connector.

Ignition "ON" & Engine "OFF".

Ground terminal 13 of ECM harness connector so that Main relay operates. Or,

Connect ECM harness connector and then, check that main relay operates if 12V is detected at terminal 58 of ECM connector after Ignition ON.

Is the 12V detected on voltmeter with operating main relay ?

YES

▶ Thoroughly check connectors for looseness, poor connection, bending, corrosion, contamination, deterioration, or damage. Repair or replace as necessary and go to "Verification of Vehicle Repair" procedure.

NO

▶ Substitute with a known-good ECM and check for proper operation.

If the problem is corrected, replace ECM and then go to "Verification of Vehicle Repair" procedure.