Random main beam
 

1997 940 Estate:
Driving along with dipped beam and main beam randomly flashes, sometimes staying on and won't go off.
Initial thought was the switch but I've tried to replicate it when parked up by wiggling the stalk and that doesn't seem to bring on the high beam when low beam is selected.
Is there somewhere else worth looking before I buy a replacement switch to see if it is that? Anyone have a switch they don't want or want to sell?
Thanks in advance

Check relays G & K on Pg8 of this pdf :

http://www.myvolvolibrary.info/Tech_...ction-3-39.pdf

They may be loose or possibly faulty. I take it from what you've said it doesn't happen in reverse - i.e. when on main beam, dipped beam doesn't join the party every so often?

thank you Sir, will look at those in the morning, may have spares from a previous 940.
Questioning the matter of not in reverse.Do headlights cut out in reverse, never noticed.

Just to clarify, i meant the situation in reverse, not when you put it in reverse gear!

In other words, driving along on main beam, does dipped beam occasionally flash on as well.

Once again, you are the man!
Headlight relay "K" (2/37) swopped it with a one I had in stock from a car I scrapped some years ago. Problem solved.

thanks again

Glad you got it sorted, i had a feeling it would be one of those two playing up. :thumbs_up:

Sadly, a week down the line it's at it again. Guess it's the switch to replace next, anyone got one for sale>

I'd double check things in the relay box and possibly try replacing the original - it may just not be sitting correctly in its socket.

Worth a try before splashing out on a new switch. Some are model-specific as well so go careful about buying one on fleabay or similar. ;) :D

some questions.

Is your car originally a UK model?

Why do you think its the high beam coming on? For instance, does the blue high beam indicator light in the dash light up when this happens?

Does your car have the DIM/DIP system that is on page 72 of the tech article DAve posted?

I would check the relay box again. Gently lever off the cover and check the contacts. If they are burnt they can be recovered with gentle work with crocus paper. I would also check with a meter that the lights are not drawing too much current; indicating there is something further downline from the relay.