Harness Testing
- With ignition switch off, disconnect main relay coupler. Connect positive probe of voltmeter to wire No. 1 in coupler and negative probe to body ground. Battery voltage should be available. See Fig 1 .
- If there is no voltage, check wiring harness between battery and main relay as well as ECU fuse which is located in engine compartment.
- Connect positive terminal of voltmeter to wire No. 5 of main relay coupler and negative probe to body ground. Turn ignition on. Battery voltage should be indicated. If there is no voltage, check wiring from ignition switch and main relay as well as fuse No. 4.
- Connect positive probe of voltmeter to wire No. 4 of main relay coupler and negative probe to body ground. Turn ignition switch to "START" position. Battery voltage should be indicated. If there is no voltage reading, check wiring between ignition switch and main relay as well as fuse No. 1.
- Connect a jumper wire between wire No. 1 and wire No. 7 of main relay coupler. Fuel pump should operate. If fuel pump does not operate, check wiring between battery and fuel pump and wiring from fuel pump to ground (Black wire).