Headlamp woes (for a change)

[andyf]

When I raise my lights with the dashboard switch, they come up together but then after a couple of seconds the L/H one starts to sag a little, then it cycles up and down, and the R/H side will then join in. However, this only happens with the engine running, they work fine with the engine off. Bizarrely I can switch the lights on before starting the engine, then start the car and they are ok. Headlamp flashers work fine, both with the engine on and off.

This has just started happening since I cleaned up the earths and connectors behind the light pods on Thursday in readiness to fit some relays.

What are the collective thoughts chaps?

[littlepippin]

Did they work ok before ?
A useful tool is a length of wire with crocodile clips at each end (you can get the bits at Maplins, or probably Halfords)
You could then run another earth from say the engine block nearby, to the earth point you worked on ? Also sometimes when the connectors are snapped back together, the male portion does not go up inside the female part, and just pushes it back through the nylon connector (the three pin ones I mean, probably red on your car) making a poor contact. Look to see if the wire sheaths are all flush where they go in the connector block.

[littlepippin]

Of course I meant to say the crocodile clip lead is temporary just to check your work.... !

[andyf]

All connections are connected ok.

Generally they worked fine before but it would do it on very very rare occasions, usually when the car hasn`t been driven for a month or more. But as I am taking the car to France in 10 days time I thought I would give everything a clean up and fit some relays. What`s that old adage, if it ain`t broke....

[littlepippin]

So I take it you rubbed the earth point back to bare metal or something, and contact cleaner on the connectors ? There are the red connectors, and the 2 x bullet connectors to clean each side.

[sonscar]

From memory the red connector supplies power to the motor and the two single wires carry the up/down signal.If the lamps are slightly loose/badly adjusted they may move the limit switch inside the motor and cause cycling.It is not always the earth sadly but a combination of several old and possibly tired components.After spending some time repairing mine I was surprised that they work so reliably.Just my 2p.Steve..

[andyf]

So I take it you rubbed the earth point back to bare metal or something, and contact cleaner on the connectors ? There are the red connectors, and the 2 x bullet connectors to clean each side.

Correct. And the white triple connectors as well, did them all. I will try your crocodile clip tip tomorrow just to see if it makes any difference.

[Beans]

Did you also clean the internals of the light switch?

[Hasbeen]

One of the problems I found with my lights was the plug the switch plugs into at the dash.

There had been some arcing in the connectors in the plug, & it took cleaning with a very small wire brush & contact cleaner to get good connectivity in this plug.

Hasbeen

[andyf]

Beans, I did not clean the switch as such but did give it a squirt of contact cleaner

[saabfast]

Better to strip it Andy, you'll be amazed at the gunk if it has not already been done before. Its quite easy, just make a note of how the brass bits go in on the rocker. Clean and cover with dilectric (silicon) grease (available from Maplins) and reassemble. I did all my switches last year and still working well.

[Beans]

Have to agree with Alan
And squirting contact cleaner in a switch might cause problems.
Especially when it is as badly corroded as this (fog light) switch shows ...



And with the light switch the various contacts are closer together, so easier to cause havoc ...

[FI Spyder]

I agree. While not as bad as Bean's photo, mine did have the green stuff. I polished the copper contacts with Brasso and used dielectric grease. I didn't take detailed enough photos so spent an hour or two figuring out which pins where normally open and which where normally closed in the three switch positions to get it together right first time. That was 10 years ago. I never had a problem with lights having cleaned the connections in the engine bay as well (as part of an overall contact/connection clean up.

[andyf]

Thank you all, you were correct. I took your advice this evening and cleaned the switch and hey presto, they seem to be working properly again, just squirting with contact cleaner the other day did make things worse. In fact both lights now rise at exactly the same speed, I can`t remember when they did that last, one has always risen a fraction of a second quicker than the other.

I now have a dilemma, do I fit the relays I have just bought or not. We are taking the car to France next week for a 10 day holiday, do I risk messing with something that is working again so close to departure.

[Beans]

... I know Beans ... have done write ups in the past but they seem to have disappeared (I can`t find them anyway) ...

Maybe it will help you with your decision when I say that I haven't fitted extra relays to both my cars (that's why you can't find the posts )
And these cars have been used in the dark over the past 20 years without any problems
(including some night long drives through Europe and lots of navigational rallies in the dark).

As I mentioned earlier, the original switch gear is pretty good if maintained properly. So if it is not broke ...