rotaryrules

Hello all I own an 88'GXL and I keep blowing my Illumination fuse, which keeps my instrument cluster lights and tail lights from working. I realize that this is caused by some sort of short, but how do I go about isolating and fixing this problem? any help is welcomed, thanks in advance---------Ren

niner

you can go about it many ways. electrical problems are never fun if your not very familiar w/ circuits

how fast does the fuse blow? does it only blow when you turn your lights on?

one way is to unplug everything on the circuit. if the fuse does not pop after that then hook stuff back up one by one to isolate the problem.

rotaryrules

greetings niner. The fuse blows a few seconds after I turn the lights on and increase the light dimmer for the instrument cluster. I have replaced the light switch so I know that's not the problem. How else could I go about isolating this problem. I own a mulitmeter and im sure it will come in handy. Thanks again in advance-------ren

Icemark

When you replaced the light switch did you replace the harness as well?

Often light related problems on the FC are related to bad connections in the light harness to the light switch connection and/or when an aftermarket radio has been improperly installed, and shorted out the illumination wire for the radio.

rotaryrules

Hello Icemark I did not change the wiring harness but I did pick one up just in case. I will try that. I think the problems began after I installed my radio, although the radio works fine and I made sure to tape up each individual wire in order to prevent a short. Any other suggestions would be greatly appreciated thanks in advance-----ren

downwinddave

The slmo9st good and the bad

downwinddave

The almost good and the bad 91 vert w/airbag
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WHAT causes this and what circuit is it...
had no dash, side markers, running lights fromt nor rear.

Icemark

if it happened after you replaced the radio, what did the Red/black at the radio get hooked up too??? it should not be connected to anything unless your radio has a dimmer input, and then (and only then) it can be used.

make sure it is covered and insulated if not used as a dimmer input for the radio.

*edit
Make sure that your installer did not confuse the red/black with ground (it is easy for a less experienced installer to do) and hook the aftermarket radio's ground wire up to it.

Icemark

On the bottom one and a little on the top one, that's the 12V+ feed into the Light switch for the parking lights/tail lights, cig lighter light, gauge lights, and all the lighted switches.

The most common reason is that the bulbs have corrosion at the sockets and/or that the plug itself has corrosion at the connection. The sometimes also the factory 15A fuse could have been replaced with an improper size.

Use a little conductive grease on the bulbs and the sockets next time you replace them and you will have reduced likelyhood of it happening again.

*edit
Your top plug has its most burnt part on the Red/black parking light/tail light wire... I would be looking at those bulbs first.

downwinddave

Thanks, Icemark.

The top is the "new" switch. Bottom is from car. Will check light sockets. Replaced the harness with one which was OK.

The old harness had the white with green stripe wire connector fried.

Dave