Operation CHARM: Car repair manuals for everyone.
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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. 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. Check the system according to the procedure described for the appropriate code(s) listed under Diagnostic Charts/Trouble Code Charts. Testing and Inspection





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.