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Glow Plug Control Module: Description and Operation

Glow Plug Controller Description (12,000lbs GVW)

The glow control system consists of the engine control module (ECM), the glow plug controller, glow plugs and the glow indicator lamp. The glow control system is operated when the engine coolant temperature is low, which allows for easier engine starting.

If the ignition switch is turned ON when the engine coolant temperature is low, the ECM illuminates the glow indicator lamp and turns ON the glow plugs via the glow plug controller. After a fixed time passes, the ECM turns OFF the glow indicator lamp and the glow plugs via the glow plug controller.

The glow plug controller has the ability to perform internal diagnostics for voltage and output state checks of the glow plugs. The glow plug controller will send an error message to the ECM via the controller area network (CAN) communication bus.