Wiring Harness, Fuse Panel, Switches and Relay Restoration

[Floating VW]

I'd been puttin' up with glitchy electrics for a couple of years, now. At first, it was just minor, annoying things like hyper-flashing turn signals when the humidity got too high, or one headlight that was a little dimmer than the other, but only on the low beams. And then the gas gauge starting getting more and more inaccurate, and the starter motor needed a couple turns of the key before it would actually engage in the flywheel. Eventually, the one low beam that was dimmer stopped working altogether, and the final straw was when I hit the brake pedal and noticed the brake lights had failed to come on. That's probably not a good thing. . .

Enough is enough! So now it's time to completely refurbish my tired, old wiring and roll back 50+ years of use and abuse.

Here is what my fuse panel looked like before I stripped and cleaned it:

Just look at that horrible, spaghetti mess!

After removing the relays, wiring and fuses, the entire fuse panel got a good scrubbing with soap and water, followed by a soak in a 5% vinegar solution. Here is the result:

Nice and clean for the first time since 1974!

I decided to re-route a couple of wires from "switched" power to "constant" power, namely the headlights and brake lights (I'm not sure why VW wanted those to only function when the ignition was switched on; more than once, this design has put me through a proper sphincter clinch, but no more!). Just one problem: the only terminals which receive constant power from the battery are terminals #8 and #9, and those are all being used by other wires. Fortunately, for reasons unknown, the #7 terminal was left completely empty by the factory. No power and no accessories connected to it. Soldering a simple copper bridge from #8 to #7 gave me four more usable terminals:

It's a little tricky to solder a large chunk of copper to the fuse panel, due to the risk of melting the plastic. If you're careful, there's a small window between where the solder melts and where the plastic melts, so it can be done.

Next task, the wiring harness! After 50+ years, the wires and spade connectors looked like this:

A little wipe-down with some acetone to make the insulation look factory fresh:

A good soaking in the 5% vinegar solution:

And here is the result:

Much better!

I suppose I could stop here, and in 50 years I'd have to do it all over again. Or, I could keep going and make it last forever! First, a spot of solder to secure the connection between the wire and the spade connector (side note: when using solder on a crimped connection, it is important that the solder is only applied before the crimp, not after. Applying solder after the crimp creates a shear point in the strands of the wire, which can cause a mechanical failure in the wire over time, especially if there is a lot of vibration):

And finish it off with a nice sheath made of shrink tube, which I'll be packing full of dielectric grease:

Unfortunately, after five decades of service, a couple of the spade connectors gave up the ghost and had to be replaced, such as this one:

Now, there are a couple types of spade connector: the common kind you get at the local hardware store (seen here on the right), and the proper kind used by the manufacturer (seen on the left):

These require a special tool to crimp them properly (which is the only Matco tool I own, and I've spent the last ten years wishing I had one that actually worked worth a damn!):

And here is the repaired wire:

While I'm on the topic of wire repairs, I suppose I should mention my preferred method of splicing two or more wires together. I thought I had cleverly invented this method about twelve years ago, and then one day I was watching a home restoration video and they used my method of splicing wires into the fuse box. They called it a "Western Union" splice, and apparently, electricians have been using it since the 1800's. Damn.

This is more or less what it looks like in case you're like me and you believe there is a place in Hell reserved for people who still use butt connectors:

And now, I get to go through this whole process with all of the other 893 different wires in the car. . . After a while, all those spade connectors turned the vinegar orange:

Once the wires and the fuse panel were cleaned and repaired, the next task on the list was the relays. My machine originally had four relays: the turn signal/emergency flasher relay, the headlight dimmer relay, the annoying relay known only to me as J34, and the even more annoying key-in-the-ignition buzzer relay.

The buzzer relay was, naturally, the very first thing I permanently deleted from the car. The J34 relay is mostly related to the seat-belt warning system, which was, naturally, the second thing I permanently deleted from the car. There is one very important thing of note related to the J34, however: the main wire from the ignition switch to the starter motor is routed through the J34 relay. The idea was to make it impossible to start the car without putting your seat-belt on first. Over time, the contacts inside the relay get dirty and can cause a voltage drop in the starter motor wire (a wire which is already prone to voltage drops due to how far it has to travel). This modification here, bypassing the J34 relay, is a great way to avoid a major pain in the arse:

And speaking of dirty contacts in the relays, here is an example of what to look for:

Inside the turn signal/emergency flasher relay, these contact points need to be cleaned. Here is a close-up:

The bi-metallic strip contact also needs a cleaning:

Here's a better view of that:

And, (not) finally, here is the refurbished, re-wired and re-connected fused panel:

Well, it's still a spaghetti mess, but it's a clean one! Not only that, but I discovered that a lot of the wires had been connected (by yours truly) to un-fused terminals. That has been corrected (with one exception: the big wire going down to the air-horns. . . Hey, I ran out of fused terminals!)

Ok, that's as far as I go for now, but there is more to come. Stay tuned for Part 2, where I disassemble and clean the light switch and emergency flasher switch!
_________________
"It's time you started treating people as individuals, rather than mathematically predictable members of an aggregate set, regardless of how well that works."

[Schepp]

Nice writeup!
The nest under the hood I've read, its called Einstein's hairdo.

The problem with a lot of the old wiring is the areas that you can't see. The tight bends and connections in the depths of the beast that have rubbed against the body for decades.

When I was in the process of pulling the old harness and installing the new one in my car, I was amazed it:
1) Still ran and worked.
2) Hadn't caught fire.

For anyone else doing this. While cleaning the connectors and wires is a fantastic start, The rest of the harness in it's entirety needs to be inspected as well.

Good on you for taking the time to go through your harness. It could save your pride and joy from a potential fire.

[Bobs67vwagen]

Nice work and attention to detail. My question to you would be about the western union. I have seen on VW factory wiring over the years that they used a clear plastic sleeve with a spade connector on each side that you then plugged a female connector to on each side to join 2 wires. This made the union removable. Which of these 2 methods would be better from a current flow standpoint, or is there no difference. Thanks Bob

[bomberbob]

I think the question is whether the "splice" or repair might need to come apart in the future. If not, then the solder splice makes it permanent. There are splices available (amazon) with clear heat shrink, and rings of solder inside. When you get the splice hot enough it melts the solder, and shrinks the plastic. Or you can use the method shown and put dual wall heat shrink over it. Dual wall has glue or sealant that melts and squeezes out sealing water out.

If you think you might want to disconnect the splice in the future, you can use those plastic covers you stick the spades into, or you can buy water proof connectors (Weatherpack, or similar) and splice them in.
So many ways to do this, just don't twist them together and wrap with electricians tape. Please don't do that unless its an emergency roadside repair.
_________________
1968 Beetle torn apart again
1990 Jetta GLI megasquirted, burning E85 (currently in storage)
2004 Jetta turbo GLI
Marion, Iowa

[OldSchoolVW's]

[OldSchoolVW's]

[runamoc]

[OldSchoolVW's]

[runamoc]

[talljordan]

I do not recommend those options for quick connects. Order from Digikey instead

The hardware store style ones are ugly and non original looking, and are not solid brass.

I recently did the same job, I purchased all connectors from Digikey.com. With them I was able to choose only pure brass with no plastic bullshit. I chose the thickness of the brass, the size of wire it accepted (20ga, 16ga, 10ga etc), and the exact width of the terminals. It also was rather cheap.

This meant that I can size the terminals for the exact wire I am working on, and I also purchased narrow ones for the tiny connectors for the fan and the like.
_________________
1972 Super Beetle, Parked until adequate restoration funding is acquired in restoration!

Wanted: Male computer diagnostic plug end

[talljordan]

Direct digikey links to what I used. They run $5 for 50 and are very high quality. MUCH higher quality than the brass multipacks on amazon.

For small wires:
https://www.digikey.com/en/products/detail/te-connectivity-amp-connectors/42743-1/288392

For medium wires:
https://www.digikey.com/en/products/detail/te-connectivity-amp-connectors/42281-1/288367

For very large wires:
https://www.digikey.com/en/products/detail/te-connectivity-amp-connectors/60635-3/294251
_________________
1972 Super Beetle, Parked until adequate restoration funding is acquired in restoration!

Wanted: Male computer diagnostic plug end

[runamoc]

[talljordan]

Conductivity doesn't matter nearly at all. Resistance to corrosion is king for connectors.

The power is travelling less than an 1/8th of an inch through the connector, and is travelling 10-20 feet through the copper wire. Resistance is proportional to cross sectional area and length.

Brass is tougher and less prone to breakage than aluminum or tin connectors. I will stick with brass.
_________________
1972 Super Beetle, Parked until adequate restoration funding is acquired in restoration!

Wanted: Male computer diagnostic plug end

[baldessariclan]

I’ll echo what talljordan states above about corrosion & durability, plus add that increased cross-sectional and contact areas in the connectors effectively reduces resistance as well. Brass hardware is extremely common and heavily used in most electrical hardware, switches, connectors, etc. — there’s no problem with it in a correctly designed application.
_________________
1971 Standard Beetle — fairly stock / driver

baldessariclan -- often in error, never in doubt...

[MTT3107]

I was in the same situation, old crappy rat’s nest of wiring, plus, I wanted to upgrade to modern style blade type .

So I pretty much ripped the existing wiring apart, replaced all the wiring to the headlights, front turn signals, and marker lights.
Installed new fuse block(s), with additional circuits for instruments, instrument lights, and electric fuel pump.

Lot of work, but worth it imho.

[runamoc]

[baldessariclan]

Your tin plating is adding resistance -- tsk, tsk...

Seriously through, brass, aluminum, tin-plated-copper, etc. connectors -- they can all work just fine if used correctly, IMO.
_________________
1971 Standard Beetle — fairly stock / driver

baldessariclan -- often in error, never in doubt...

[runamoc]

[Floating VW]

[Floating VW]