rear window defrost?
 

I have a 1984 190D and the rear window defrost does not work, the fuse is fine and the light turns on but it does not work. Is there a relay? Any ides would be great, thanks.

On a W123 there is a relay hidden right up under the dash (driver's side).

So yes look for a relay.

They usually have part numbers on them - bang the numbers you find into google / ebay / fastlane / other places(!) to see what description comes up.

I don't mean to add more work to your agenda, but pull the rear pillar covers and inspect the connections on each side if and when you are feeling saucy.

Thoise are both good ideas. The defroster element draws a lot of current so all the connections (and relay contacts) have to be very clean and tight.

Good idea, how do they come off?

damnit... now you're makin' this all difficult!

They are kinda cheasy. They use friction clips to hold them in place... please be gentle or you'll end up cursing me for suggesting that you remove them.

Pull the front top corner away from the pillar, then just pull them towards the front of the car. Not in any other direction. Some wiggling may be required.... use finesse, not force.

If I break any Ill send you a pm! Ha Ha.

Then just get the hammer out now and be done with it!


Sadly, after this week you will not see me around much anymore. I have gotten rid of most of my parts and I will not have the time to be as active with MB anymore. (sadface)

Why? You still have your car?

There are TWO fuses, I think you checked #19, but have you checked #6?
Also there's a combination relay (rect black box in fuse box) which completes the circuit from fuse #6 to provide (15 minute timer) power to rear defrost.

If you have service manual (look for the electrical diagram) & If you have a DMM...you can check for power & continuity of the rear defrost right at the relay.