fressssssh

So I was on here like 2weeks ago telling you guys about how my 944 was smoking out of the dash and the problem seemed to be centering around the headlight switch. I took it out and replaced it and the wiring to it, also replaced thwe relay and fuse. Well now that all that's done, my flip ups still don't go up and down nor do my parking lights come on or anything in the instrument panel. Idk what the problem would be. Any help is appreciated.

83 944

did you check for voltage to the switch? and at the headlight motor?

Preeze

I had issues with my lights too, no smoke or anything but my taillights would go out and so would my dash lights when I turned on the headlights.
I replaced the headlight switch and all was fine....except that it cost $70 for a new one.

fressssssh

Did you also replace the wires to the switch.?

Preeze

nope I didn't.
for me it was just the switch.

FRporscheman

My friend is having this exact same issue with his '83 right now. I can't figure out what it is after 2 hours of work. I replaced the headlight switch with 2 spares I had and that wasn't it. I pulled the fuse box to check the wiring, and it all appears OK. I checked the fuses, all OK. I checked the red wire at the headlight switch plug, and it has constant 12v. The yellow/black wire has 12v from the ignition.

The instrument lights, tail lights, headlight motor, and fog lights do not work. There was no smoke or anything, it just happened. The only thing that DOES work from the headlight switch are the actual headlights, so we have the lights flipped up and they just stay up. He says he drags his brakes to show red lights from the rear so he doesn't get pulled over.....

I cleaned the bellhousing ground last year, I cleaned the taillight ground today, the battery ground looked fine. I forgot about the headlight ground on the front frame rail until right now - could that be the culprit?

Here's the weirdest part of the problem: When I try a jumper wire from the red wire (constant 12v) to any of the wires that lead to things like tail lights, etc, the volts at that jumper (compared to the chassis) go from 12v to 0v. I'm so lost.

mazdaverx7

i had just experienced the SAME problem. a tug on the wiring at the fuse panel corrected the problem.. i believe, and another member here has turned me onto this, that there are poor connections at the fuse/relay panel causing this issue. seems that the proper fix is to depin each connection one at a time and clean each connection. since i tugged around on the wiring the problem has resurfaced once and a tug fixes it.

FRporscheman

Crap.... that's about the worst thing it could be. But it gives me a place to start looking. Thanks, I'll post if I find the answer.

Jet-Tech

I often see this problem with aircraft electrical problems where the voltage meters as good but the component being powered will not operate.

Voltage checks alone do not always prove a good solid source of current capability. Think of voltage supply as water pressure and the current (amps) as a direct correlation to the size of the pipe. If you have a large pipe with the required pressure and no restrictions, you can get good water flow. If the pipe has a blockage or kink you will see pressure but when you demand flow it will not be adequate.

If the wire in the circuit does not have good solid connections (without corrosion, frayed wiring etc...) the amount of current that can flow will not be sufficient to perform the required functions especially for high current demand circuits such as lights, window motors, starters etc.... You will see the correct voltage but the voltage will disappear under load.

I always use a meter to check for voltage but to confirm good current flow I will use an auto brake light bulb to which I have soldered 2 wires that I can connect into the circuit as a good load. Poor connection points will drop the voltage before it gets to the unit that requires the power. Using the brake light bulb as a load will help trouble shoot these types of problems.

As well, always check that the ground side of the circuit is good. Always endeavor to use the ground source in the circuit to prove the return side of the circuit rather than using an easily accessible chassis ground.

Good luck in your diagnostics.

FRporscheman

Thanks for the great tips, I'll keep them in mind.

ZR8ED

fressssssh

Well now that this old thread was brought back to life.... I have managed to get my flip-ups to go up and down, but still no parking lights, instrument panel, or brakes. I don't know how to fix it. What exactly did you tug on rx7? The fuse box, or the wires connecting to it?

Marajit

Sounds like progress.
Now, tell us how you did it.

mazdaverx7

wasn't the RX-7, it was my 944. i pulled on the wires connecting to the fuse/relay box. it moved the wires enough to make a connection and all of the lights work as they should. this leads me to believe, and as another forum member suggested, a faulty connection at the pins at the fuse/relay panel.