The wiring diagram in the Haynes Manual does not match what I have coming out the door. I also checked Jeff Bowlsby's site.

Which wires go where:

Click to view attachment

Not totally positive but If you have 2 male connectors behind the plastic "wall" then the brown wires go behind the wall and the red ones go in front of the wall. The red color wires should be a different color though.

Buck

My car is a 72, but I was told it might have been first sold in Canada. It has a Feb 1972 build date.

I was looking at the Haynes Manual and "Fig 9.68 wiring diagram up to 1971, USA" shows the connections I have: red wires on the back, brown on the front. However, when I connect them, they blow the fuse. They also blow the fuse when they are connected red in front, brown in back.

It seems to matter which wires are connected to which terminal. Any ideas on how to find this out? I got more fuses, but I hate to just keep trying and blowing fuses.

I'm pretty sure the door switches are the cause because when they are disconnected I can put a fuse in and nothing happens.

I thought I might try to see which wires are connected at either end with a continuity test and thought this might tell me which wires go where. Thoughts?

I would appreciate any ideas for figuring this out.

What? Built in '72 and licensed as a '71?

I suspect you have a dead short in the wiring going to the interior lamp and when the wire from the door is grounded, it shorts out the circuit. Is the interior lamp connected the right way? Is the wiring to the door buzzer disconnected or shorting out?

Oops! That was a typo. I fixed it.

Lamp has no bulb, but it appears to be connected correctly. I've never heard the door buzzer go off so I might not have one. I'll check and report back.

One way to save fuses is to wire a sealed beam headlight cross the fuse holder of the fuse that blows. As long as the short is present, the light will be on, and the resistance of the filament prevents wire harness damage. Disconnecting components or moving the harness will lead to the short when the lamp goes out.

Remember, a fuse only blows when current flow is high. Because a switch is not a load (and should have almost NO resistance) it can not cause the fuse to blow by itself.

I'll try to look at my '73 in the morning. I can't imagine they could be wired much differently

Have you figured this out? Your wire colors match the 71 USA Diagram and they seem to function differently than a 72-73 car like mine.

The red wires coming into the switch have batt voltage from fuse 11. (Check with a voltmeter. Have a good fuse installed.)
The other red wires provide voltage to the buzzer as far as I can tell. They should be across one set of switch contacts. (I believe the buzzer gets ground through the ignition switch.)

The brown wires should share the other switch contacts, and provide ground for the dome light.

You'll have to check the switch and see which pair of terminals connect when you actuate the switch.

I tried checking how the wires go on my door switches, but I couldn't get them out without a fight. I think they're different anyway.

Let me know how this goes. I'm curious.

Not yet. This is what I have figured out so far:
1. The wires from the door switches are connected from left to right (so no broken wires).
2. There is power from one of each of the red wire groups on either side. So one set of red wires does not seem to have power.
3. The grounds (brown) wires are connected to the dome light on the driver side.
4. I have continuity on one set of leads on the switches from front to back with the button out, but not in. The other set of leads don't seem to have continuity either way. I cleaned one of the switches with Simple Green to see if that helped. It did a little.

I need to check the buzzer to see if it's even installed. I hesitate just because the relay board has so much stuff on it, it's old and I'm afraid of breaking/cracking/shorting out anything and it's a pain to deal with.

I may just figure out a way to just get the dome light working, or just tape off the leads and put the switches back and leave them un-hooked. I don't really need a dome light.

Check all four wires for continuity to a ground. Maybe?
Set Voltage meter for continuity, put red on a wire and put black on chassis. If it beeps, it's shorting out.
Not an electrician, somebody tell me if that is all wrong.

I have a spare switch that I checked with an ohm meter. I also only had continuity on one "pair" of contacts. I think my switch is bad. It's basically two separate switches in the same housing. ( Called a momentary contact double pole, single throw switch.)

I would insulate the red wires and just try to get the interior light ground circuit working through the good contacts. If you touch the brown wires together, does the dome light work?


You said that one set of red wires has power and the other doesn't. That is correct. One side is supposed to have power, go through the switch, and then to the buzzer, so the other red wires shouldn't have power. The left and right switches are wired in parallel so either switch completes the circuit.

Those are definitely the wires and a switch from a 71....I know because mine is like that.

Tbrown4x4 has got you on the right track.
One set of wires runs the interior light and the other the key in the ignition buzzer.
Buzzer relay is on the fuse panel under the dash.

Get yourself a 71 wiring diagram if you don't get anywhere with the above suggestinosand start identifying and tracing the wires.
You'll narrow down the issue pretty quickly.

BTW, I had to install a new ignition switch and it didn't have the provision (wire) for activating the key in the ignition buzzer....so no buzzer for me.

Also....you need to continuity check your 4 pole door switches as many of these are defective after all this time....they just wear out, etc.
Often tough to find functioning ones as they are not available new any more.

So here's what I ended up doing:

I bought the single-connector door switches at a VW place (I think the 914-6's have these types, as do older Bugs, etc). I wired the grounds to them and now I have a light, but I have to switch it off and on manually. I just taped up the red wires. I attached both sets of ground wires to the switch so I can turn the light on by flipping the switch button up or down.

Is it ideal? No, but at least I have a manual dome light and no annoying buzzer.

I think the switches are bad. Even after cleaning them, only one side worked. They are not available new, and are expensive anyway.

My 73 had these same switches.

They wear out.

Those are switched grounds and a very interesting wiring scheme by the German Eng. It troubshot this circuit a coouple of years ago and got it to function as intended. Took quite a few hours.

Looks like the OP has had enough. I do see exposed wire through the insulation so that would be needed to be addressed first.

Was the chassis harness schematic ever found? It has all the info needed.

Yeah, I'm done and ready to move on. I fixed the exposed wire by the way.

I have the Haynes manual. I think the switches are bad. I was able to get the dome light to work manually.