Electronic Control Unit (Ecu)

The ECM controls all functions of the GMCCS. The ECM consists of a printed circuit board enclosed within a metal box. The ECM receives signals from the data sensors and switches. These signals are processed by the ECM for controlling the EFI, ESC, ISC and EGR systems.

The GMCCS has a fail-safe feature designed into the ECM. If the ECM malfunctions, a back-up circuit is activated to assist in getting the vehicle to a service facility. During this mode of operation, driveability will be minimal. The "CHECK ENGINE" light will also be lit when the computer malfunctions.