Indicators (+ int wiper & rear screen) stop working when stationary randomly

[SilverSaloon]

Hi

1994 W124 estate

when i am stopped at a junction, indicating (any direction) the indicators have started to stop flashing (and remain off). When this happens i also cannot work the rear screen demister (light comes on and goes off straight away on the button), and the intermittent wiper (setting 1) doesnt work. Other wiper functions work though.

If i move the car it suddenly starts working again.

Seems random. I've checked the fuses and all OK (even replaced some even though they looked fine just incase).

Any ideas? Maybe a relay? if so where is it?

Thanks!

derek

 

[Dec]

All the things you mention are involved with a multi function relay, the intermittent wiper gets a kick start from this relay but position 2 and 3 are not involved with the relay so that is why the other wiper settings are working ok.

Don’t know your car but on a C180 it is one of the relays under the fuse box under bonnet, not sure which one, others will know better.

Dec

 

[SilverSaloon]

Thanks Dec.

Do you know if there is a visible way of knowing if a relay is dud (like a fuse) or is it just a case of replacing and see how it goes?

 

[bolide]

I think it's the N10 relay in the relay box behind the fusebox. You could try removing in and reseating it - or removing it, throwing it away and replacing it!

Nick Froome
www.w124.co.uk

 

[Dec]

I’m not an expert on that Derek its not like a standard relay, there could just be a poor connection, fault being triggered by lack of motion at traffic lights.

Would suggest, if you can locate it you could perhaps try wiggling it when the fault is present to see what happens, apart from cleaning/checking connections there would be no other alternative but to replace it.

Photo, as an example of mine, not sure if it is number 2 or 3 Nick might know which is which.

Dec

 

[SilverSaloon]

I think it's the N10 relay in the relay box behind the fusebox. You could try removing in and reseating it - or removing it, throwing it away and replacing it!

Nick Froome
www.w124.co.uk

thanks i'll take a look and try and clean the contacts etc 1st.

otherwise, i have another 124 so i will swap them around and see if the other car gets the fault and then source a new one if required.

 

[Number_Cruncher]

Yes, these are the symptoms of the N10 comination relay.

On mine, with similar symtoms, I opened it up, inspected with a magnifying glass, and found some dry solder joints. I reflowed them, and it's been fine ever since.

http://www.detali.ru/cat/oem_mb2.as...GM=717.433&CT=F&cat=44R&SID=54&SGR=040&SGN=03

Part number 78 on the drawing.

Be careful with it, it's an expensive relay!

 

[SilverSaloon]

Thanks - i'll check this out tonight.

As it works 99% of the time i am hoping its just a dirty connection or something.

 

[Number_Cruncher]

If it is a failed solder joint on the PCB, then, reseating the relay may make it work again - for a short while! Just tapping the box may be enough to temporarily re-make the bad connection.

Or, in other words, I would be very much surprised if you can make a lasting repair without doing something a bit more involved.