Mercedes-Benz 300E Automatic Shutdown Relay Replacement at your home or office.

What is the Automatic Shutdown Relay all about?

When you turn the key for your ignition to start, many different things happen. The fuel pump turns on, sending gas from the tank, through the lines, to the injectors. The battery sends voltage to the ignition system, which creates a spark, igniting fuel vapor and starting your engine. However, if the automatic shutdown relay (ASD) is not working, none of this will happen.

The automatic shutdown relay controls the power that is supplied to the ignition, the fuel pump, and the injectors, as well as other components. It is only activated for a few seconds during cranking, and is then turned off. Depending on the make and model in question, the automatic shutdown relay could be located under the hood, under the dash, or in another position.

As with any other electrical component, your automatic shutdown relay is subject to wear and tear, and frequent stopping and starting of the engine will exacerbate that wear. Eventually, it will fail and you’ll be left with a vehicle that doesn’t crank.