Electrical Gremlins

[Crysdale]

I have pulled my 72 914-2.0 out of moth balls (sitting 12 years safely covered in the garage). I've had it serviced and all the fluids changed and some bits replaced (battery ,bulbs, tires, and a few other things). It struggles to start, but runs well and drives great.

What I'd like help on is some crazy electrical issues. Here are the symptoms....

Intermittent issues (all worked 2 days ago???)
-Brake lights not working
-Singles not working
-Aftermarket oil pressure and temp not working
-Wipers not working
-pop up headlights (Didn't work on my drive, but they came up and turned on when I park car and tried them)

Not working recently
-horn
-fog lights (did work before service)

Here is a crazy one.....
When i hit the break petal the gas gauge stops working and the 'alternator' light comes on.

I checked the fuzes and they look good.
I should point out, emergency flashers work

Any idea where I should start and does anyone have a wiring diagram?

[PCA7GGR]

Clean all your grounds:
- where your brown wires are attached to the body
- light sockets (battery terminal brush works well for this)

[Dave at Pelican Parts]

Originally Posted by Crysdale

Here is a crazy one.....
When i hit the break petal the gas gauge stops working and the 'alternator' light comes on.

Fuse #8 (or maybe #9?) being popped will produce this behavior. Check all the fuses by pulling them out one at a time and inspecting. Sometimes a fuse can blow but will look OK sitting in the holder; pulling it out of the holder will show that the metal part is now two pieces because they will fall to the floor.

Other symptoms might be caused by one or more blown fuses as well.

Time to dig into the wiring diagrams and look for common points between all of the things that are not working.

--DD

[Crysdale]

Thanks for the input. I was a little panicked when you said check the brown ground wires, but that was a very useful lead. I started by checking the fuzes since I'm very familiar with them. Then i start checking the lights since many of them were malfunctioning.

I found a loose ground wire on the tail light! I cleaned it and connected it and the signals started working 'better' The turn signals were working, but one brake light was still not working.

I thought i just replaced all tail light bulbs, so I didn't think it was the bulb. After messing around swapping bulbs it figured it it was a the socket. I messed around with the socket connections until I go the tail lights and break lights working!

The gas gauge and alternator/generator light started behaving properly when i hit the break (probably because i fixed the tail light connections). The oil temp and pressure were still not working..... After starting the car a a few times I noticed the pressure gauge bouncing up briefly.

I thought I could live with out the oil gauges for bit now that i got all the signal and break lights working. fortunately I discovered after some more poking that the gauges would come on for a second when i started the car. After some poking I figured out it was related to the ignition switch???? When I start the car, if the oil gauges aren't working, if I turn the key back just a tiny bit and they would work!! Short in the ignition switch maybe???? Oh well, at least I can make them work in this quirky way....

So the head light still still didn't pop up......but then i turned them on tonight and they started working. Maybe something to do with the ignition switch fix??? The Windshield wipers start working again also

So most my short temp problems are band-aided. I still need to get the fog lights and horn working, but the longer term plan is do a major overhaul with the tail lights since they seem to be a weak link.

I'd love to update them to LEDs and make all my connection issues go away and get brighter lights out of the deal. i might look into that. Does anyone make them? Just a small bright LED socket that i can wire into a 12V circuit.

Not great solution, but i had a great time driving the car today and got some thumbs up, some people really appreciate a nice well loved old car

Anyhow, i just wanted to share my finding for the next person reading this to solve their problems.

[porschetub]

I would strongly recommend you change the ignition switch ,they can cause a lot of strange faults until they fail completely,the ones our host sells are best,$10 from memory.