Engine Control Module: Service and Repair
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More supporting gear
Torque wrench
Use the factory procedure with the right tightening tool.
Manual-based work becomes much easier when you can torque correctly.
Shop on Amazon →Trim tool set
Useful for clips, covers, and trim pieces called out by the manual.
Most manual procedures assume you have a good trim removal kit.
Shop on Amazon →Multimeter kit
Great for electrical troubleshooting and manual-tested circuits.
Electrical work in manuals often needs a meter more than another wrench.
Shop on Amazon →1. Disconnect battery ground cable.
2. Disconnect numbered and lettered connectors from ECM.
3. Remove ECM mounting hardware, then the ECM from the passenger compartment.
4. Reverse procedure to install.
NOTE: Replacement ECM's are not equipped with engine calibration units (PROMs). If the PROM is to be reused, care should be taken when removing it from defective ECM. See Prom, Replace for proper removal procedure.