I need your help Guys

[hormone]

Headlight problem again but not the usual.

I have suddenly developed a problem with my pods dropping whilst driving.

I have found this a trifle disconcerting when driving down country lanes at night!

I traced the fault (I thought)to the light switch and found one of the plastic spring loaded 'nipples' that keep pressure on the contacts damaged. As the car is 25 years old this year I put this down to wear and replaced the damaged plastic 'nipple'.

Unfortunately the problem has returned tonight & I could smell a plasticy burning smell.

The switch is getting very hot and I suspect the main beam contact is the problem.

Has anyone had this problem or any ideas as to what is causing the switch to overheat. I am confident that the connector to the switch is making good contact.

Help!!

[digga951]

Sounds like a live cable is going straight to earth somewhere. I take it this is on the 200, with the SD1 type light stalk? They are quite crude and have a lot of wobble in them, so could it be that the stalk has dropped a little and is bridging a couple of contacts together?

Give us some more details on which car its on, and how your lights operate. For example, do your pop up lights only come up when you select dipped beam, or on sidelights too?

Either way, maybe just a wire going to ground and thus heating up, or the contacts inside the switch touching each other where they shouldn't. A new switch may be the easiest thing to try before you start tracing wires.

Dan.

[adam quantrill]

If it's the 400SE then these switches are a bit suspect, it might just be time for a new one. The headlights are all done via relays AFAIK so if there's something loading the circuit heavily I'd suspect the side/rear lights. I once had a bulb that had shorted internally - so it might not even be the wiring.

[Hormone]

Thanks Guys.

This is on the 200 (although I do have a problem with the switch illumination on the 400, but I'll leave that for another day).

The lights are operated by the usual toggle switch. This is what is getting hot & melting the plastic piece that makes keeps the contact in place.

The column switchgear is Ford and the dip high beam is the usual push/pull on the left hand side.

I had problems this morning & could smell the plastic melting, the high beam was not used at all.

The first position of the switch gives you the sidelights & the pods stay down then the second position gives the headlights & raises the pods.

I would appreciate any help/ideas where to look as the car is in daily use and I am gradually changing the car's interior colour when I suddenly lose all forward lighting at speed.

Because of my work patterns I have not been able to drive a distance with just the sidelights on to see if the switch still overheats but maybe can do this later today.

Thanks again so far.

Brian

[chedder]

It's possible that one of the headlamp pod motors is not switching off, this puts quite a large load through the switch causing it to heat up and melt.
Try switching the lights on and see if one of the motors gets warm, this will indicate if this is happening, possible causes are a stuck contact in the motor, crank arm out of adjustment on the pod, or a faulty relay.

One other item to check, on low beam try and see if their is a faint glow from the blue main beam light on the dash, if their is, this indicates that that the contacts for the push-pull column stalk have stuck together (dried grease normally) this puts additional load on the light switch also.

Edited by chedder on Friday 23 February 09:41

[SEvans]

Brian, I think the column and associated switches are TR7....mine are. The centre console switches I think are early TR7 or Allegro. I would try replacing the headlight switch first as the contacts do seem to corrode and this causes arcing and heat. Once the plastic has melted I think there is not much you can do with it, and it may be allowing the contacts to short. I would also check the fuses and relays and make sure nothing is melted and that you have the correct rated fuses (not sure how you check this but we could compare notes as I think I did make a note of the fuse layout on mine). Try reseatting the relays and fuses as it may be a bad connection.

[dickymint]

Can you pinch the switch off the 400 and see if it cures it?

[leorest]

hormone said:

...I have suddenly developed a problem with my pods dropping whilst driving...

Just a thought. With my electronics diagnostics hat on. Can you think of anything which has changed or been disturbed at or around the time of the problem starting? You know the sort of things...
Change rear bulb; checking/changing a fuse/relay; adjusting steering column; poking around behind the dash for another reason (stereo/dash illumination)etc. etc..

Best of luck solving this and in the meantime make sure you've got a spanner to hand, in case it starts to smoke and you want to disconnect the battery pronto! Might be worth while checking all the fuses are sensible ratings in case someone fitted a bigger fuse in the past.

[jchase]

If it [your 200] is like my old 280i with the fuse box in the engine bay, the fuses and relay connections seem to suffer from cathodic corrosion. You get some connections with green goo and others with brown bubbly stuff. Can't be good for the electrickery! Maybe you are getting a short around the headlight &/or pod lift relays causing too much juice to be drawn from the switch.

-jim

[Hormone]

leorest said:

[ Can you think of anything which has changed or been disturbed at or around the time of the problem starting? You know the sort of things...
Change rear bulb; checking/changing a fuse/relay; adjusting steering column; poking around behind the dash for another reason (stereo/dash illumination)etc. etc..

The garage has put a new connector on the alternator recently, come to think of it the alternator is charging at 14 volts even with lights on. This does seem high.

Brian

[degz]

Hi Hormone I had a problem with my 200 lights, the main beam was coming on with the dip, my local TVR garage said it was a common wiring problem and it took them a short while to fix. I forget the details. the coluum arm is Layland, TR7 and similar as are the switches.
Have you tried night vision bin's?

[hormone]

degz said:

Hi Hormone I had a problem with my 200 lights, the main beam was coming on with the dip, my local TVR garage said it was a common wiring problem and it took them a short while to fix. I forget the details. the coluum arm is Layland, TR7 and similar as are the switches.
Have you tried night vision bin's?

Hiya Degz.
The trouble with night vision bins is that I regularly drive to work very, very early in the morning.

[hormone]

I have driven all the way home with sidelights on and the switch did not get warm so suspect that the problem is on the headlight circuit.

I will keep you all posted as to what i come up with but please keep your ideas coming.

Thanks

Brian

[leorest]

hormone said:

I have driven all the way home with sidelights on and the switch did not get warm so suspect that the problem is on the headlight circuit.

I will keep you all posted as to what i come up with but please keep your ideas coming.

Thanks

Brian

Ok now pull the relays for the main lights and try driving home again but this time on dip beam. If the switch stays cool you can then try putting each relay in and see when it starts to get hot. Try to work out where you can divide the circuit up to see which side the problem is on.

[Hormone]

leorest said:

hormone said:

I have driven all the way home with sidelights on and the switch did not get warm so suspect that the problem is on the headlight circuit.

I will keep you all posted as to what i come up with but please keep your ideas coming.

Thanks

Brian

Ok now pull the relays for the main lights and try driving home again but this time on dip beam. If the switch stays cool you can then try putting each relay in and see when it starts to get hot. Try to work out where you can divide the circuit up to see which side the problem is on.

Thanks for that. Guess where I'll be all day tomorrow.
I had to abandon the car this morning as the pods went down & wouldn't come back up!

[Hormone]

Well the good news is I think I have sorted it but the bad news is I don't know for sure what it was!

As I only had yesterday to sort it out I removed, cleaned the connections of the lighting circuit wiring from the headlight bulbs & earths through to the switch. I replaced the headlight bulbs, cannabalised another switch to replace the part that had part melted.

I also removed the alternator connection and cleaned it & all the earth connections.

Although there was no evidence of it arcing I think it was the 'newly replaced' connection to the alternator itself that caused the problem. This would also tie in with when the problem started.

I managed the 40 miles to work with the light switch hanging lose so that I could easily tell if it was heating up & quickly disconnect it as I had used my only spare light switch.

So I shall put all the trim back next Sunday although I am tempted to find out why the fibre optics don't work on either car.

Thanks again for all your help Guys.

Brian

[350zwelgje]

Congratulation with solving the problem. And I know your feeling: do a lot (or sometimes nothing!) and problem went away/is solved - and you don't know why... I call it the mystery of the wedge.

The fibreglass optics often don't work due to:
- not a lot of light coming from the bulb (even when the bulb gets hot enough!)
- bulb not working....

The fibre optic stuff works, but only if during 'maintenance' the fibres were not damaged. Replaced the bulb on mine, and there is something more I can see at night when it is very dark. People installed powerful leds, to get more light with less heat. If you do a search on the forum, you probably will come across it.

Rob

[leorest]

Well done butty!
Fingers crossed it doesn't come back
Leo

[Hormone]

350zwelgje said:

Congratulation with solving the problem. And I know your feeling: do a lot (or sometimes nothing!) and problem went away/is solved - and you don't know why... I call it the mystery of the wedge.

The fibreglass optics often don't work due to:
- not a lot of light coming from the bulb (even when the bulb gets hot enough!)
- bulb not working....

The fibre optic stuff works, but only if during 'maintenance' the fibres were not damaged. Replaced the bulb on mine, and there is something more I can see at night when it is very dark. People installed powerful leds, to get more light with less heat. If you do a search on the forum, you probably will come across it.

Rob

BULB! I don't have a bulb just a black wire that terminates in a ferrule that sits in a white plastic holder. I assumed the light (ha ha )just shone out of the end.

They did work on the 400 so it could be a feed wire to the distribtion cylinder loose.

[Hormone]

leorest said:

Well done butty!
Fingers crossed it doesn't come back
Leo

Twas ok again this morning so looking good!