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 spiritual successor to CHARM, I recommend you try it!

Link: lemon-manuals.la or lemon-manuals.org.ua

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Engine Control Module: Description and Operation

ECM Location:






The Electronic Control Module (ECM), located under the instrument panel, left of the steering column, is the control center of the fuel injection system. It constantly looks at the information from various sensors, and controls the systems that affect vehicle performance. The ECM performs the diagnostic function of the system. It can recognize operational problems, alert the driver through the "CHECK ENGINE" light, and store a code or codes which identify the problem areas to aid the technician in making repairs. The ECM is replaced as a complete unit, there are no serviceable parts in the ECM.