Strange electricals W124

[Devallon]

Hi Guys !
I'm new to list and just bought a W124 300TE Estate. Very happy with it, 240000 miles and apart from being sluggish until it is would up, drives very well !
I have 2 electrical problems, and would appreciate some knowledgable help.
1 My rear wiper fires up every time I go into reverse. Not just when front wipers are on, all the time. Is there a relay somewhere that is stuck, or a familiar wiring short that someone knows about ?
2 The dashboard lights for the heater controls and down to the window switches and gear lever etc are all out. bulbs seem ok - is this a hidden fuse job ? All fuses seem ok in fuse box.
Any ideas would be appreciated.
Many thanks
Bill :-D

 

[turnipsock]

I'm sure it's one feed that does all those lights, red/white wire from memory but I'll check this tomorrow unless anybody knows already.

 

[television]

I had a feeling that they all come from the little red fuse on the rear of the instrument cluster

 

[Myros]

and I think the wire is Grey and purple?

I had the same fun with ours when we got it. I'll have a shufti in my haynes manual later.

 

[turnipsock]

Haynes says the dash lights controled by the dimmer is all Grey/Blue wires. Have you checked the dimmer switch isn't turned right down?

 

[television]

Haynes says the dash lights controled by the dimmer is all Grey/Blue wires.

And the little red fuse will be the one that has blown

 

[Devallon]

Sorted !

Thanks guys for the advice. It turned out to be the little red fuse behind the dash, I just soldered up the break and it is fine. Why don't they mention it in Haynes ?

Still got the rear wiper thrashing away like a demented puppy as soon as the gear lever goes through reverse (auto box). Is there a relay that controls the rear wiper that gets fed when the reverse light come on ? Can't seem to find it anywhere - any clues ?

Cheers Bill.

 

[television]

Thanks guys for the advice. It turned out to be the little red fuse behind the dash, I just soldered up the break and it is fine. Why don't they mention it in Haynes ?

Still got the rear wiper thrashing away like a demented puppy as soon as the gear lever goes through reverse (auto box). Is there a relay that controls the rear wiper that gets fed when the reverse light come on ? Can't seem to find it anywhere - any clues ?

Cheers Bill.

Before we move on to the wiper, the practice of soldering up a fuse is not good news, You must replace it, it is a protection device, and if that cant blow,the next thing in the line that could blow could prove to be very expensive

 

[Devallon]

You are absolutely right Malcolm, I just wanted to repair it to make sure this was the problem and not a part of it. New fuse will be bought next time I'm near a Mercedes dealer. The bit I soldered was not the fine element but a connector to it that looked as though it was scratched at some point. Still a temporary repair though.
Bill

 

[television]

You are absolutely right Malcolm, I just wanted to repair it to make sure this was the problem and not a part of it. New fuse will be bought next time I'm near a Mercedes dealer. The bit I soldered was not the fine element but a connector to it that looked as though it was scratched at some point. Still a temporary repair though.
Bill

No promises, but I will see what I can find later in the day for the rest.

 

[Devallon]

Anyone had the problem of the rear wiper wagging its tail wevery time you go into reverse ? I believe it is supposed to happen when the front wipers are on, and reverse engaged, but it happens always in reverse - or every time I pull away from park, by going through reverse ! Any suggestions welcomed. Thanks
Bill

 

[beemerjay]

Still got the rear wiper thrashing away like a demented puppy as soon as the gear lever goes through reverse (auto box)

I can't recall but does this only happen when the front wipers are on?

I have a dim recollection of a few cars doing this when you select reverse when the front wipers are on?

MAybe you got an experimental model

 

[Devallon]

I can't recall but does this only happen when the front wipers are on?

I have a dim recollection of a few cars doing this when you select reverse when the front wipers are on?

MAybe you got an experimental model

But it does it every time ! Rain or shine - makes the car look like an anorak wearer in the middle of summer ! :-?
There must be a relay somewhere fed from the front wipers that energises the rear when a feed from reverse is present, but I can't find it. Otherwise I have a short in the wiring so the rear wiper get a feed from the reversing lights. It's jolly annoying old chap !
Bill

 

[MotardMan]

The relay is in the boot, LHS. I think it was tucked in behind some trim but the factory manual will tell you for certain..