ZPmadA

I need your help. I'm having problems with my lisense plate lights and instrument lights. The fuse box does not tell me which fuse is used for the lisense plate light. Could someone be so kind and pull the instrument light fuse and see if the lisense plate light is wired to it? I think the 944 fuse box changed each year this is why I need someone with a 1986 944. I have a 1986 944 turbo so if you have the same car as me that would be even better.

This is important to me because I need to know if I have 1 problem blowing my instrument fuse causing both my lisense plate light and instrument lights to not light up, or if I have two isolated problems. Both my lisense plate and instrument lights used to work, but I touched something and ofcourse I up anything I touch If the lisense plate light shares the fuse with the instrument lights, I was thinking of disconneting the dimmer because the lisense plate light will obviously be wired before the dimmer and see if my short thats blowing the fuse is prior to, or after the dimmer. Let me know what you guys think. If I disconnect the dimmer, will I mess things up even more because of unused current that should be going to the instrument lights cause my wires prior to the dimmer to get hot and melt?

jjjr944

I'll pull tomorrow morning and let you know...

Jerry 86 944 NA
62k miles

Chris_924s

#1 Welcome to Rennlist.

#2- check your grounds in the hatch. Trust me. The wiring to the LP lights is a feed from the interior, but the ground in the hatch should fix this problem- is your fuel guage weird as well?

PM me or e-mail me if you need wiring diagrams.

Jerry- i'm calling you tomorrow- be ready for beer.

Techno Duck

The dash lights share the same fuse with the license plate lights, atleast on my '87 it is. I dont think they changed through the years. I dont remember the number, but its like a 30amp fuse, and is on the bottom right portion of the fuse chart (the underside of the fusebox cover). It says "Number plate...etc" as the description. You may want to check if your rear bulb holders are loose for the license plate light. I couldnt figure out why mine was constantly blowing the fuse. Ended up i did not secure the light holder correctly and it was shorting out on the chassis, blowing 4 perfecttly good fuses until i realized what was happening.

Waterguy

The wiring diagram for the 1986 944 (all models) shows the power for the licence plate lights comes from fuse#38 (7.5 amp), and is shared with the instrument lights. It branches off the instrument light circuit just before the dimmer. Your idea of disconnecting the dimmer is a good one, and won't hurt the wiring. There are just two branches to the circuit at that point; one to the dimmer and one to the licence plate lights. If the fuse blows with the dimmer disconnected, then the short is in the wiring to the licence plate lights.

jjjr944

I pulled the #38 fuse (Instrument lights) from the underhood box today with lights on. Rear license plate lights went out as well when fuse was pulled.

Sounds like you are on the right track.
Good luck.

Jerry
jjjr944
86 944 NA

Mongo

sounds like something on that circuit is definitely grounding out and causing the fuse to blow. My license plate light hasn't worked since I bought the car. It doesn't really bother me and no other electrical issues are apparent yet with the exception of a faulty coolant sender.

Welcome to the List and I hope you find a solution to this issue. Good Luck to you

ZPmadA

I disconnected the dimmer and installed a new fuse for the instrument lights. The lisence plate lights now work and the fuse isn't blowing! I was pulled over the other day because my plate lights were out, luckly no ticket but it is fixed now. I have isolated my short at or after the dimmer Looks like I have a nightmare ahead of me. I have to figure out how to remove my MOMO race steering wheel before I can pull the guage cluster out and do a visual inspection of the sockets. Standard allen wrenchs arent doing the job I think I need metric to remove the steering wheel. I'm going to need to know every socket after the dimmer that needs to be tested and I'll PM you Chris or anybody else that can help me with this information?

nine-44

I'd try swapping the dimmer if possible, it's most likely the problem. It is a potentiometer and would most likely cause a short if it fails. You may be able to access it from under and behind the dash. Or pull that trim peice, it has a bolt in the end behind the dash end cap, two under the lil trim cover by the vent and one at the bottom of the column in at about a 45 deg angle. Good Luck

ZPmadA

oh wow your right! I removed the dimmer (this was dimmer #2 that I bought on ebay, #1 was original and melted) and basically bypassed it with a wire. Looks like that dimmer I bought on ebay was no good. I'm very happy my wires are ok, I would like to thank the Porsche Gods for that. And thanks everyone else for helping me out. ! ! !