Operation CHARM: Car repair manuals for everyone.
Manuals through 2025 now available!

Our trusted friends have launched a new website named LEMON, which has newer manuals. It also contains all the CHARM manuals.

LEMON is the logical successor to CHARM, I recommend you try it!

Link: lemon-manuals.la

Electronic Control Module (ECM) Replacement


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.