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Engine Control Module: Testing and Inspection

Fig. 24 Engine control unit terminal identification:





1. Start engine and allow to reach normal operating temperature.
2. Connect voltmeter negative lead to (P) terminal of control unit Fig. 24.


Fig. 25 Engine control unit testing procedure:





3. With engine operating as shown in chart Fig. 25, connect voltmeter positive lead to terminals indicated and note voltage. If voltage is not as specified check circuit of terminal being tested. If circuit is normal, replace engine control unit.