Glow Plug Control Module (GPCM) - All Others
The glow plug system consists of a GPCM, glow plugs, and the associated wiring harnesses. The glow plug on time is controlled by the GPCM and functions on the basis of the engines RPM, engines torque, engine coolant temperature, air temperature, BARO sensor and battery voltage. The GPCM is located behind the right hand side front wheel well cover. The GPCM supplies voltage to the individual glow plugs, which it does by duty cycling direct battery voltage. Glow plug on time normally varies depending on battery voltage and the engine coolant temperature. The voltage to the glow plugs is provided through the GPCM eight high current drivers from the vehicle battery. Battery voltage is supplied to the GPCM, the power distribution box, then through the vehicle harness, which connects to the GPCM. The ceramic instant start glow plugs can operate up to 20 minutes. The GPCM may activate the glow plugs during an extended idle at cold ambient temperatures. The GPCM provides battery voltage for approximately 2 seconds to heat the glow plugs, then modulates the voltage to 7 volts to maintain temperature. The module also contains three drivers for the reductant heating system. The GPCM monitors and detects individual glow plug functionality and control. Concerns detected by the GPCM are transmitted to the PCM over the controller area network 2 (CAN2) circuits.