Glow Plug/Controller
WARNING: This page is about a different car, the 2004 GMC Sierra, 2004 GMC Cab & Chassis Sierra, 2004 Chevrolet Silverado, and 2004 Chevrolet Cab & Chassis Silverado. However, it is still accessible from the selected car via links, so may be relevant.
The glow plug controller is a solid state device which operates the glow plugs. The glow plug controller is connected to the following circuits:
- The fuel heater ignition 1 voltage circuit
- The battery voltage circuit
- The CAN communication circuit located between the engine control module (ECM) and the glow plug controller
- The engine ground circuit
- The glow plug supply voltage circuits located between the glow plug controller and the glow plugs.
The glow plug diagnostic circuits are directly monitored individually by using a separate transistor to control current to each glow plug. Individual diagnosis is thus possible for every glow plug.