Operation CHARM: Car repair manuals for everyone.

Engine Control Module: Description and Operation

This vehicle has an Electronic Control Module (ECM) used to control the fuel system. The ECM receives input information from various sensors in order to control the air/fuel ratio. The ECM sends a variable signal to the injector. This changes the "ON" and "OFF" time or pulse width of the injector. The fuel pump, Torque Converter Clutch, and various other systems are controlled by the ECM.

NOTE: Whenever an ECM is diagnosed as being faulty, perform the ECM circuit resistance check, located in SPECIFICATIONS/ELECTRICAL AND ELECTRONIC SPECIFICATIONS, before replacing the ECM. This check will prevent possible damage to the new ECM.