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Glow Plug System: Description and Operation

Description
The glow plug system is used in order to assist in providing the heat that is required in order to begin the combustion during the engine starting at the cold ambient temperatures. The glow plug relay the switches power to the glow plugs and is commanded ON and OFF by the PCM. The glow plugs are heated before and during the cranking, as well as during the initial engine operation. The PCM monitors the glow plug relay output voltage which indicates if the relay is following the PCM commands.