Fuse #8 blowing

[NebraskaSpider]

It started out by one day I noticed that my dash lights were out and I noticed everything on the fuse 8 was out. So first thing I did was put a new fuse in it. It worked fine for about 5 drives, all lights and everything. Then it blew again, so i put another fuse in it and it was fine for a drive or two. Then it blew again so I threw another fuse it it, which immediately blew and now it blows every time I put a new fuse it it. So I went and checked all my bulbs which were good. I checked all my grounds which were clean and tight. I checked the connections at my gauges, checked my trunk light, checked my cigarette liter. Nothing seemed wrong.

Any suggestions?

[rlux4]

The power goes through your instrument panel rheostat. I had a problem with mine that turned out to be a broken connection on one side of the resistance coil. There are a lot of bulbs and fiber optic lights on that line, so hopefully it's something simple like a short in your rheostat.
Ron

[NebraskaSpider]

I pulled the dash to have a look at all the connections behind the gauge cluster and to have a look at the rheostat and all the connections look good. No burt or exposed wires. Is there a way to test the rheostat or should I just buy a new one? Do part suppliers sell this item, I couldn't find any listed?

[rlux4]

You can check the resistance change as you turn the knob by using an ohmeter on both terminals. In my case I knew something wasn't making contact inside the case when I had no continuity passing through the unit.
Ron

[spider2081]

I believe the trunk light wire is connected to fuse 8. Many cars do not have a trunk light and the wire inadvertantly shorts to ground. My prints show a yellow/black wire for the trunk light.
Also on the back of fuse 8 are 2 yellow /black wire spade connectors. Removing one at a time would help isolate the problem. One of the wires feeds the dash lights, cigar lighter lite, and the lights on lite in the spedo. The other feeds the trunk light, right hand tail lite and side running lite, and right license plate lite.

Hope this is some help

[gchocevar]

Hi,

I Checked the schematics and the following are connected to fuse 8 (H):

Front left parking lamp
Parking and tail lamp indicators
Rear tail light lamp
Front left and rear right side marker lamps
left license plate lamp
Cigar housing indicator
trunk light
instument cluster lights
optical fiber lamp
hazard warning light

If you don't have an electrical schematic they are posted at various websites.

Good luck
Greg

[mdrburchette]

I'd check the trunk light too. I thought I was doing good by putting a bulb in my trunk light holder and I kept blowing a fuse for no reason. Of course, it occurred to me after I pulled the dash and lights out to check everything. The trunk light doesn't work unless the lights are on. I realized it was an accessory I didn't necessarily need.

[NebraskaSpider]

Well, after pulling the dash, checking the rheostat, and checking just about everything else I could, I figured out my problem. I am a little embarrassed to say it was a grounding issue after all. Seems the ground that goes into the hazard switch was loose and was only making a connection some of the time. So I tightened up the connector and all works fine now. I guess I didn't check ALL the grounds well enough.

Thanks for all the help.

[majicwrench]

a loose ground will not cause a fuse to blow.

[NebraskaSpider]

Hmm...well I guess I'll wait an see since it worked for a while and then blew after a few drives when this first started happening. It was blowing every time I put a fuse in it an turned my lights on while I was working on it and after tightening up the ground that goes into the center of the hazard, it worked. I assumed the loose connection was shaking around while I was driving.

[NebraskaSpider]

I must have some problem with the turn signals because now my #1 fuse is blowing every once and awhile. Same thing as with the #8 fuse...it blew then it was fine for a few drives, then it blew again when I hit my blinker. So I guess I'll keep troubleshooting, and ideas are welcome.

[TiiTommy]

Has anyone figured out the blowing fuses in this string? Fuse A on my 1981 Spider 2000 blows after a few seconds with the key on. I have found a few shorts (probably unrelated as fixing them did nothing to fix the blowing fuse). There is some sloppy looking splicing going on related to the A/C control switches, but I can't find any sort of wiring documentation to see if this is part of the problem or not.

I suppose I will continue to disconnect and test.

If I come up with an answer, I will be sure to post it.

Cheers,

TiiTommy