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Sat May 28, 2016 1:37 pm

So my brake lights have not been working correctly and I traced all the wires and I found one that was loose on a connector. I tightened that up and the lights work fine except when I have the headlights on. When the headlights are on and I brake, only the right side brake light goes on and the running light goes off on the left with no brake light either. I've been over the wiring diagrams extensively and I cant seen to find anything wrong. The only thing I could think might be wrong would be something in the light switch or a relay. Any ideas?

Sat May 28, 2016 2:13 pm

Remove the left bulb and clean the socket out all nice and shiny, then clean and tighten both ends of the ground wire for that fixture.

Sat May 28, 2016 2:22 pm

Sounds like a bad ground. Remove tail light assembly and clean area it mounts on and make sure the screw holes and screws aren't corroded, then remove each bulb and clean and polish the contact areas where the bulbs sit to make sure all bulbs are making a good connection (side and bottom), also remove each wire and polish connectors to insure they are making good connection. Now is a good time to replace all the bulbs back there as its not that much $$. I solved that problem on my '67 and '71 and greatly improved my rear lighting by removing everything and I made two 'U' brackets and mounted LED boat trailer lights using my stock lenses for the outside of the bus with longer screws that mount the lens to hold the 'U' brackets holding the trailer lights up next to the lens on the inside. 10 times brighter lights and turn signals and still looks stock from the outside. Less than $40 for everything and I saved the old reflectors and bulb assy.s incase I ever sell and the fool wants to change back. I feel so much safer and don't worry about some fool not seeing my old dim lights and rear ending my bus.

Sun May 29, 2016 10:40 am

Okay, so I cleaned and polished both light sockets, connectors, grounds, and the connections on the bulbs. Still having the same problem. I looked at some of the diagrams for newer buses (70 and up) and I noticed that each of the tail light housings have their own ground wire where I only have that on my right tail light (I'm assuming because this housing is aftermarket). So I tried adding a ground wire to the left tail light housing since I thought it wouldn't hurt anything but to no avail, it did nothing. Anymore ideas anyone?

Sun May 29, 2016 11:35 am

Run a wire from the light socket to the ground you added and retest.

Tail light retro fit (early)
http://www.thesamba.com/vw/forum/viewtopic.php?p=7634535#7634535

GD
Tcash

Sun May 29, 2016 11:35 am

Solder the wire directly to the outer part of the bulb socket, sometimes those aftermarket units lose continuity between the case and the socket where it's pressed in.

Sun May 29, 2016 4:02 pm

Alright. So this time I soldered the ground wires to the bulb sockets on both tail lights and the problem is still there, except now its the left that works with the headlights on ](*,)

Sun May 29, 2016 4:11 pm

Something's still not making contact, possibly the bulb to socket shell.

What's happening here is the brake or tail light is using the other filament in the bulb as a ground path through the rest of the bulbs in that circuit, when you power that second circuit the ground is suddenly gone and the light no worky.

Those aftermarket fixtures are sketchy when they're new, the cure is a couple of universal snap in bulb sockets from your FLAPS.

http://www.autozone.com/electrical-and-lighting/un...02934_0_0/

Wed Jun 01, 2016 11:28 am

So I think I might have found the issue. Since the problem only arises when the headlights are on, I thought I turn to the headlight switch. Turns out the rheostat in there is broken and I'm thinking that might be causing the problem so I'm looking at getting a new switch. If it isn't the switch, at least I will have a non-broken one. Since I have a 68, it is looking pretty hard to find a headlight switch in stock anywhere. I have seen a couple of these though but the pin orientation looks slightly different and the rheostat is on the opposite side as the one in the car.

Only 6 of the 8 pins on mine have wires on them though. My question is if this switch would work in my application or not.

Wed Jun 01, 2016 11:43 am

68Transporter wrote: ... the rheostat in there is broken ...

That seems to be a common problem and will cause various types of wonkiness. My engine would only start or run with the switch in the parking light position. Turning the headlights on or the parking lights off would cause the engine to die. Very difficult to diagnose that problem, but very possibly not the source of your problems. The early bay light switches are a breeding ground for electrical gremlins.

Aloha
tp

Wed Jun 01, 2016 1:12 pm

Found one on RockAuto with the corrected terminal layout and put in an order. Lets hope this works!

Wed Jun 01, 2016 2:15 pm

The old rheostat in our 69 uncoiled and caused huge problems including shorts and burning inside the switch. Got a new switch and the first time I rotated it the rheostat uncoiled on it too. Everything else worked fine and the light dimmer was stuck in the "full on" position. So everything now works fine.

Wed Jun 01, 2016 4:28 pm

For the future
Broken rheostat

Good rheostat

OB Bus wrote: The old rheostat in our 69 uncoiled and caused huge problems including shorts and burning inside the switch. Got a new switch and the first time I rotated it the rheostat uncoiled on it too. Everything else worked fine and the light dimmer was stuck in the "full on" position. So everything now works fine.
I would cut the wire out before it starts causing problems and leave it on full bright. Dimmer switch my ass there is only can't see and off anyway.
Tcash

Wed Jun 01, 2016 4:38 pm

So you're saying that I should just remove the rheostat and just run it like that correct? It won't cause any problems other than the loss of the dimmer?

Wed Jun 01, 2016 5:29 pm

68Transporter wrote: So you're saying that I should just remove the rheostat and just run it like that correct? It won't cause any problems other than the loss of the dimmer?

Yes, but any pieces left inside might cause future problems and it may not solve your brake light problem.

Aloha
tp

Wed Jun 01, 2016 7:01 pm

68Transporter wrote: So you're saying that I should just remove the rheostat and just run it like that correct? It won't cause any problems other than the loss of the dimmer?
Yes
Tcash

Wed Jun 08, 2016 9:21 am

So I got the new switch in today and I was wondering if there was any particular way that I should remove the rheostat so that it doesn't break into a bunch of little pieces. Any help Tcash?

Wed Jun 08, 2016 9:35 am

You're saying you bought a new headlight switch? If so, run it as is.

Removing the rheostat is a method of successfully using an old switch.

Now that said, the headlight switch has nothing to do with brake lights. If you're still having brake light issues, get a test light and check the brake lamp signal back at the rear light fixture. If the test light lights (ignition on, brake pedal pressed), then the issue is in the fixture itself or its ground. If the test light doesn't light, the problem is upstream: turn switch, 4-way flasher switch, brake light switches, associated wiring.

Trace the signal. Divide and conquer!

Wed Jun 08, 2016 9:43 am

I believe Tcash was saying to remove it right off the bat so that it can't cause any problems in the future. I will never use the dimmer feature so are you saying that I should not remove it since the rheostat will never been used and abused?

Wed Jun 08, 2016 10:08 am

68Transporter wrote: I believe Tcash was saying to remove it right off the bat so that it can't cause any problems in the future. I will never use the dimmer feature so are you saying that I should not remove it since the rheostat will never been used and abused?
No need to remove it on a new switch unless it breaks. I would leave it.
Use a small pair of diagonal cutters and cut the wire out.

Good luck
Tcash