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Engine Control Module: Testing and Inspection

ECU Connector Pin Identification:






1. With ignition off, disconnect multiple pin plug from ECU.
2. Turn ignition on. Using a voltmeter, measure voltage between terminals 9 and 5. Battery voltage should exist.
3. If battery voltage does not exist, measure voltage on plug connected between terminal 8 and ground at the central electric board. Battery voltage should exist.
4. If battery voltage does not exist, pull out relay XVI and bridge terminals 30 and 78. Recheck voltage as outlined in step 2.
5. Connect a jumper wire between terminal 17 of disconnected ECU connector and ground. Fuel pump relay should activate and fuel pump should operate.
6. If fuel pump does not operate, check fuse No. 13, relay XVII and fuel pump relay.