Faulty cylinder #2 glow plug
Cylinder #2 glow plug harness is open or shorted
Cylinder #2 glow plug circuit poor electrical connection
Faulty Glow Plug Control Module
Engine Light ON (or Service Engine Soon Warning Light)
n the diesel engine, air alone is compressed in the cylinder. Then, after the air has been compressed, a charge of fuel is sprayed into the cylinder and ignition occurs, due to the heat of compression. Eight glow plugs are used as an aid to starting.
Control of the glow plugs is accomplished by the Glow Plug Control Module. The nominal voltage for the glow plugs is 5.4 volts. When the ignition is turned On, the Glow Plug Control Module applies 7.2 V for 2.2 s, then 5.7 V for 0.8 s, and then 5.4 V until 1200°C (2192°F) is reached. The maximum voltage of the system is 10 V. While the engine is running the voltage will vary between 4.7 – 10 V when in closed loop control to maintain a glow plug temperature that ranges from 1150° – 1180°C (2102° – 2156°F). The temperature and the power consumption are controlled between the Engine Control Module (ECM) and the Glow Plug Control Module within a wide range to suit the engine’s pre-heating requirements. Each glow plug is energized individually. This capability yields more optimum heat times for the glow plugs, thus pre – glow times can be kept to a minimum for a short wait to crank times and maximum glow plug durability.