Electronic Control Module (ECM) Operation: Notes

1986 GMC S15 Jimmy 2.8 R, 4WD, AutomaticSECTION Notes

The Electronic Control Module (ECM) is the control center of the CCC system. The ECM is located in the passenger compartment behind the driver's seat on "G" series vans. The ECM is located behind right side of dash, near glove box, on all other models. See Figure .

The ECM senses engine operating conditions, processes input signals, and controls the various systems that affect vehicle performance. The ECM also performs the diagnostic function of the system. It can recognize operational problems, alerts the driver through the "SERVICE ENGINE SOON" light, and stores trouble codes. The ECM senses and/or controls the following:

RENDER: 1.0x

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