Was installing Super Bright white LEDs to replace my instrument bulbs and had all the gauges done except the speedo. All was glowing fine until that point. I replaced the two in my speedo and flicked on the light switch to test if they were properly situated and working and then I heard a very faint hisssssssssssssssssssssss, and then the smoke started pouring out from behind the dash. All the dash lights then went out.

Needless to say, I felt sick. At least the smoke was very faint. I checked all the fuses and WTF, they were all fine.

Then I found this article which says, that the instrument lights are one of the electrical systems Porsche/VW didn't bother to fuse. Thanks a lot P/VW!

http://www.dietersmotorsports.com/tech/1998/12-98a.html

Prevention is ridiculously cheap and quick. Simply add a $3 fuse holder with a 3 amp fuse to the instrument lights wire at the switch. The wire is black with blue rings. Just place a female and male spade connector on each end of the fuse, plug the thing in to the wire you disconnected, and shrink wrap the ends, or tape it like crazy, and test. And don't forget to disconnect the negative from the battery first. Test with out the fuse, plug the fuse in and your done.

Please 'bump' this post to keep it near the top so everyone sees it.

Hey Rick,

Sorry to hear about your issue. I will be under there tomorrow and will get mine squared away. Thanks for posting the pic.

Jim

Perhaps the late models were fused, I just made mods on some dash lights and blew a fuse.

. I was checking why I did not have a light in the speedo. The wire was off of the spade on one of the bulbs, I plugged it in and the whole thing fell apart and shorted on the speedo housing. Now all the gauges are dark. Checked all the fuses and they are good. No burnt wires. ?? What next??
CCL

sorry for being thick but this is off fused off the light switch yes?

Rick,

Was it the 71 you were working on that was not fused? I have a 72 that I will inspect when it gets in. Thanks for the post, it will be very useful if my setup isn't fused.

Interesting ....

Interesting... but how come we are seeing a 911 dash, not a 914????


(Yes, I can tell the difference from the back....)

Thirty years ago I smoked a wire in the dash of my 73. It was the high beam indicator light, and the bulb was fine. My only guess is that a hot wire abraded through the insulation of a ground wire.

same wire that was cooked and sidelined my 70 for half the summer!
_

Stephan, yes, the fire occurred on a 71 914.

Clay, The pic was to take of the same work performed on a 911. Good eyes.

James, yes you want to fuse it to the back of the light switch connector as shown in the pic.

I had a massive electrical fire in my 74 about 25 years ago.
I was rebuilding my spedo and replacing the plastic gauge face in my
tach with glass. When I put it back together all was fine until I went to
start it later than night and turned on the lights. The engine starting
running really rough, the lights were really dim. I revved the engine a bit
to keep it running and then a few seconds
later massive smoke started pouring out from under the dash.
I killed the engine but the smoke kept pouring out.
When I peeked under the dash I could see the yellow flames of fire.
I had to run back in the house to get a wrench to disconnect the battery.
In the morning I discovered that I had not connected all the spades back
to all the gauge lights. One of the spades was touching the housing. Can't
remember if it was a tach light or a spedo light.
Anyway it fried about 5 wires and they were completely fused together.
Didn't take that long to fix but I was shocked at how such a small thing could
escalate into such a massive short that didn't end when the key was removed.

--- bill

I just reviewed the electrical diagrams for all years of 914. Up to 1972, the instrument bulbs were unfused, as Rick pointed out. However, starting in 1973, and for all years subsequent, the instrument lights were powered by the luggage compartment fuse, S7. This is a 7.5A fuse, 7th from the left. I verified on my '74 that when this fuse is pulled, the instrument lights turn off.

If your car is a '72 or earlier, I'd suggest that you rewire to the later spec, rather than add an inline fuse.

One correction to the picture from the 911 for a 914; the wire from the light switch to the dash lights is black with a twisting blue line. Behind the instruments, it attaches to the black line with the blue rings.

It is not quite as effective a setup, but it far easier to attach the fuse between where the black with blue twisty line connects to the black with the blue rings behind the fuel gauge.

Dave has an excellent suggestion and it might be easier and more 'factory'.

I read somewhere about the amperage required for the dash gauge lights was pretty low, hence the 3 amp fuse (I have a 3 amp in both the teener and 911).

How would you go about wiring it for later model. Are you saying to disconnet the power for the instruments lights and putting it over to the S7 fuse ?