Hi, I have a 1980 240D 4 speed manual.

Is the glow plug timer relay separate from the glow plug relay that is located on the wheel well, driver side, under the hood?

I ask this because a search on Pelican Parts has the timer relay as a separate relay (link below). I think the glow plug timer relay is located below the steering wheel. Is that correct?

https://www.pelicanparts.com/More_Info/0015452232.htm?pn=001-545-22-32-MBZ&bc=c&q=glow%20plug%20relay

If you Glow Plug Relay came from the factory is on the left fender well there may or may not be a temp sensor in the cylinder head connected to it but the timer would be with in it.

Just open the hood, ignore the glow plug light and have someone turn the key to the pre-glow position and time how long it takes for the really to turn off.

The saver box relay I believe for older vehicles. There is another fender well relay that rarely shows up made by Schuler or shuer on 240Ds. It is another expensive one like the silver box one.

Gol plug relay with no temp sensor wire going to a sensor on the cylinder head have a temp sensor built inside of the relay.

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84 300D, 82 Volvo 244Gl Diesel