Rebuilt headlight switch?

[Jd21476]

Can I have the headlight switch rebuilt for my 1983 911? The rheostat for the dash lights is not working and new ones are expensive. Ive seen them for about 1/2 the price of new on Ebay but I dont want to buy one and find out it doesnt work either.

[911 Rod]

If it can be it's a shame because there are a ton of them in landfill.

[Walt Fricke]

Maybe. I had one go bad on me while driving in the mountains in the winter in 1985 - not the dash dimmer, the headlamp part! Luckily, I had fog/driving lights at the time to get home on.

When I got home I took it apart. A pretty impressive design inside - ceramic block with the various contact parts inlaid. They were silver in color, but I don't know if they were silver or tin or a mixture. I could see where overcurrent had blackened/melted some. A good craftsman might be able to replace or repair.

I forget what the rheostat part was like - pretty likely a coil. The slider wears the exposed copper winding, and at some point an open develops. But you wouldn't think anyone would adjust the brightness all that often.

Using relays reduces the current going through the contacts, which would be a good thing generally (but not for the rheostat part).

Not made to be disassembled -- you have to bend tabs. Can't do that too often.

I installed a used one from a junk yard - worked fine, still does though the car is not a race car and headlight switch seldom used at all.

[911 Rod]

Walt. Without the relay does power not go through the switch all the time?

[Walt Fricke]

The most important added relay is for the high beams, so that their current doesn't flow through the little contacts on the steering column stalk. So putting that relay after the stalk switch deals with its current.

The low beam current flows through the switch unless you add a relay after the headlight switch for it.

None of this will help with a problem with the rheostat which controls the brightness of the dash lighting.

I think the clever way of doing that is to switch to LEDs, and to install the module you need to control LED brightness separately, with its own knob.

[faverymi]

Or just buy a new switch and keep it original

[T77911S]

^^^
the problem is Porsche had a very bad design for the headlights, in fact for most of their wiring.
the big one is the fuse is AFTER the switch and hi beam switch. next as mentioned is all the current going thru the switch.
fuses should be located as close to the power source as possible.
I put in 2 relays for the headlights but did not cut any wires and left it so that if needed to go back original it could be done easily.

[Iciclehead]

Ya know, I am in the middle of my rewiring and looking at that wretched headlight switch with wires festooned all around it and I think I am going to take a different approach.

I am going to put an eight pin plug between all the wires going to the switch and the switch itself. Then I can make a short pig tail with nice fat wires between the switch contacts and my new plug - one per contact - and then do all the connections on the other end of the plug.

That way I can wire up the switch on the bench, make sure the connections are good, reduce any risk of pins bending and potentially shorting and make absolutely sure I have all the wires going into/out of the switch connected together where needed. I can also then put in some fuses here and there perhaps or even route some wiring through the fuse panel and make it "proper".

Yes, I know I am adding a plug, but when I look at the number of plugs in the wretched wiring harness (it is an early '89) then I can't help but feel that one more, well crimped, high wattage plug is not going to make all that much of a difference.

Anyone think this is especially nutty or ??

Thanks

Dennis


http://forums.pelicanparts.com/porsche-911-technical-forum/185692-fitting-6-speed-g50-89-carrera-new-post.html

[Teutonics]

Originally Posted by Iciclehead

I am going to put an eight pin plug between all the wires going to the switch and the switch itself. Then I can make a short pig tail with nice fat wires between the switch contacts and my new plug - one per contact - and then do all the connections on the other end of the plug.

You could also add your fuses into the pigtail wiring... instead of cutting original wires or adding a separate "fuse pigtail" (which is what I did). So kind of the same end result...

[Iciclehead]

Originally Posted by Teutonics

You could also add your fuses into the pigtail wiring... instead of cutting original wires or adding a separate "fuse pigtail" (which is what I did). So kind of the same end result...

I like the way you think....puts me also in mind of putting a small ATO fuse panel underneath there somewhere so less is dangling and more is firmly mounted.

I will mull on the matter....

Thanks...

Dennis