This listing is for Item Description Glow plug relay to suit Mercedes Benz M642 this is the 6 cylinder CDI Diesel motor from Vehicle listing below Sprinter Vito ML class W164 GL class X164 R class W251GL (X164/166) kW HP GL 320 CDI (X164.822) OM 642.940 165 224 03/06-06/09 GL 320 CDI BlueTEC (X164.825) OM 642.820 155 211 07/08-06/09 GL 350 CDI BlueEFFICIENCY (X164) OM 642.820 165 224 05/09-12/10 GL 350 CDI BlueEFFICIENCY (X164) OM 642.872 195 265 10/10-> GL 350 CDI BlueTEC (X164) OM 642.820 155 211 05/09-> M-Klasse (W164/166) kW HP ML 280 CDI (W164.120/121) OM 642.940 140 190 09/05-06/09 ML 300 CDI BlueEFFICIENCY (W164) OM 642.940 140 190 05/09-> ML 300 CDI BlueEFFICIENCY (W164) OM 642.940 150 204 02/10-> ML 320 CDI (W164.122) OM 642.940 165 224 08/05-06/09 ML 320 CDI BlueTEC (W164.125) OM 642.820 155 210 07/08-06/09 ML 350 CDI (W164.122) OM 642.940 165 224 05/09-03/10 ML 350 CDI (W164.125) OM 642.940 170 231 02/10->

A glow plug relay in a car is an electrical component that plays a crucial role in the starting process of diesel engines. Its main function is to control and provide power to the glow plugs in the engine. Glow plugs are heating devices that are necessary for diesel engines to start successfully, especially in colder temperatures. The relay acts as a switch, allowing the glow plugs to warm up before the engine is started.

This relay is typically connected to the ignition switch of the car and the engine control unit (ECU). When the ignition switch is turned on, the ECU sends a signal to the glow plug relay to energize and activate the glow plugs. The relay then delivers power to the glow plugs, which heat up and begin to warm the combustion chambers in the engine. This preheating process ensures that the diesel fuel ignites properly when the engine is started, even in cold weather conditions. Once the engine is running, the relay deactivates the glow plugs as they are no longer needed for combustion.