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ECU Test Harness Installation

Test Harness And Terminal Location:





If the test for a failure code requires the Engine Control Module (ECM) test harness, remove the right door sill molding, pull the carpet back to expose the ECM. Unbolt the ECM bracket.

Turn the ignition switch off, connect the ECM test harness. Check the system according to the procedure described for the appropriate test being run.

The purpose of the Test Harness is to eliminate the need of back-probing the ECM harness. If the Test Harness is not available, CAREFUL back-probing of the ECM harness will have to be done for any given test procedure.

How To Properly Probe Electrical Connections:





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