elctrical problems

Making some progress.

Fog lamp, and headlight now working.

Still got a problem with the brake light. The tail light is working, and the bulb looks ok.

I am not sure how thes stop/tail lights work. There are two electrodes in the housing and two filaments in the bulb. I am wondering why both lights don't come on simultaneously.

Because only one electrode is required for each filament. The circuit is completed by the bulb housing earthing through the holder. One filament is the tail light, the other is the stop light. Likewise one electrode is tail and one stop.

ok, thanks

so, the fact that the tail light works means that the bulb must be earthing through its holder.

The filaments are alright, so it looks like the elctrode in the housing may be causing the problem.

Any idea how I can remove the housing so that I can check the wiring.

Thanks

Sorry. Mine's a 406 so I can't help on that question. Is the other stop light working, if not you may have a switch or fuse problem.

Yes, the other stop light works.

I still can't see how to get at the wiring

Evidently there is a plate inside the boot that can be removed. I can't see it

Thanks for responding.

Best wishes

"user1517" wrote: > Yes, the other stop light works. > > I still can't see how to get at the wiring > > Evidently there is a plate inside the boot that can be > removed. I can't > see it > > Thanks for responding. > > Best wishes > > > > S

In my experience, failure of lights in old cars is usually caused by bad earthing. In practice this means that the bulb outer body is not making good electrical contact with the lampholder. Spray everything with WD40 and leave to cook. Wipe off the excess and then try to remove the bubs. Then thoroughly clean the inside of the bulb holders if there are signs of corrosion. After cleaning, a bit of petroleum jelly (Vaseline) smeared on the surfaces will help to prevent further corrosion. Don?t forget to clean the bodies of the bulbs, too.

ok,

But wont the vaseline act as an insulator?

Thanks

Grease will insulate but Vaseline acts as a conductor. It is also good practice to smear the battery posts with Vaseline before fitting the terminals.

Keith

ok,

I'll give it a go.

Best wishes

ps. I always thought that vaselene was a type of grease

Just a thought.

I have no problem with the tail light in the same bulb. Does this mean that the earthing between the bulb and the case must be ok?

Thanks

You can only tell by experiment. I had a car years ago where only one tail light came on. When you pressed the brake pedal down that tail light went out and the stop light on the otherside came on. That turned out to be earthing. Bear in mind that one filament is a higher wattage than the other, I think sometimes the easiest path to earth is through the other filament. You could try getting some long lengths of flex to connect both bulb holders together and run straight to the earth post on the battery. That will tell you if earthing is the problem after which you can sort it out.

Keith

Thank you

Sp