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Engine Control Module: Testing and Inspection





If the inspection for a particular code requires voltage or resistance checks at the ECM connectors, remove the right door sill molding and kick panel. Pull the carpet back to expose the ECM. Unbolt the ECM cover. Turn the ignition switch off, and connect the backprobe sets and a digital multimeter as described below.





How to Use the Backprobe Sets
Connect the backprobe adapters to the stacking patch cords, and connect the cords to a multimeter. Using the wire insulation as a guide for the contoured tip of the backprobe adapter, gently slide the tip into the connector from the wire side until it comes in contact with terminal end of the wire.





CAUTION:
- Puncturing the insulation on a wire can cause poor or intermittent electrical connections.
- Bring the tester probe into contact with the terminal from the terminal side of wire harness connectors in the engine compartment. For female connectors, lust touch lightly with the tester probe and do not insert the probe.