quattros.org

Still tracking this post, anyone have ideas on what is creating this situation? Bad ground or switch?

I am sure someone is better at wiring diagrams than me...<ul><li><a href="https://forums.audiworld.com/4000/msgs/37218.phtml">original post by gated?</a></li></ul>

Whitjr

When I had my prob, the illumination for my gauges/speedo cluster/main light switch/radio/temp fan switch all went out at the same time. Upon investigation and some swearing at the incompetant fools that develpoped the Haynes manual wiring diagrams, I found that these all were connected via a ground and positive wiring. The ground wiring was also the part of the circuit that was fried and had to be replaced. I may have mentioned that I purchased the whole circiut from a parted-out '86 4000s.

Since you can "jimmy" the main light switch, perhaps it's just the switch. If it's not that, I'd take a real good look at the ground wiring.... If you've got big hands like mine, you'll have to get creative and remove the bar gauges at least to get to that area. A volt meter is also handy here. I think I have spent a total of three hours doing this. Maybe you can do it quicker, but I checked every connection I could see.

gated?

Could you be more specific on what ground to look for and the bar gauges. I find that refrences to a certain part of the car are lost when comparing to my Bentley manual.
Would the actual wire be melted or?
The switch is good and I have an extra one as well to get rid of. 84kq
Thanks for tracking my post, it seems I can use all the help I can get. J

Whitjr

That goes from gauge to gauge and also up to the illumination for radio/heater/all those little lights NOT in the main dash. Look for the lights in the back of each gauge or switch. Electric windows illuminations are different circuit, so don't look there.

I've been away for a couple of days getting recerted in Advanced Cardiac Life Support; and I apoligize for taking so long to get back to you on this.

My brown wiring was actually toasted w/ the insulating brown-colored plastic melted. Postive side was unharmed by the destruction. The wire itself was intact, but a hazard in it's gooey state.....

I tried to re-insulate the wiring w/ blk electrical tape, but found that there was just too much of it to do that to.

The ground wiring to the main light switch was where I first discovered the problem of melt-down, and was where I had the smoke eminating from. Those wires are primarily blue w/ grey striping on my car. I tracked the melted wiring down from there. Had to patch the main switch wiring some, but replaced all the other damaged wiring as previously mentioned. I don't like working on the main dash area, as my hands are really big [I could never play the violinwithe these fingers!]

If U wanna sell your xtra switch, I'd be interested. My switch is, well, funky, and I bought an '86 model switch which is not an exact match, so am reluctant to install it.

Please let me know if there is anything else I can assist U with, and I hope that this helps!

gated?

Yeah I have a 84 switch I would sell. soory for the late reply. I still have no idea WHAT TO FIX ON that car. Do I have to take the dash off or just the instrument cluster? What about to install a new light relay system? Thanks J