: Mind bender!? Strange cluster and dash illum problem!? Any service guys? GM Geek?

12-30-06, 12:00 AM
It just happened. And I am in the middle of trying to figure it out.I would appreciate any suggestions or thoughts to it.

It started with me pulling apart my power folding mirrior switch. (2002) the lights are out, and i wanted to double check the bulb and pull it out to find some replacements at the dealer or radio shack. I was measuring at the bulb to check to see if I was getting power...slipped and shorted out the dash lights. No biggie, just a fuse....the int dome, outside park, folding mirrior function and door switch lights are still working.
So I check all the fuses, they seem good. Checked under the hood and driver side dash. Nothing?!?
One thing I noticed...when I have the park lights on, the Fuel/computer fades out.
WTF.. Are the instrument lights trying to ground down the fuel computer line??
It's dark, I'll try again tomorrow.
But I would very mush appreciate any ones input. It should really only be a fuse?!?!Am I missing a fuse location??
I did pull out one bulb from the folding mirrior switch (there are 2). Do the dash lights need to be on one closed circut. Would the one missing bulb affect the rest of the dash lights? It shouldn't!?!?

Thanks and sorry for the long story!!

12-30-06, 12:22 AM
is this the switch you talking about ?


12-30-06, 12:26 AM
Yup thats the one.
I've got it hook up to my alarm as an ext to fold. It has never had a problem?!?
Until I tried to measure 12v at the bulb!!

12-30-06, 12:33 AM
one more time, what exactly is not working
1. temp. disconnetct your alarm wire from the switch (possible feed back happend when you shorted it

12-30-06, 12:48 AM
this is schematics of power mirror switch. I looked, and it does have something to do with illumination. however, can't find anything about that light bolb
Have you tried fuse box on the right side of the dash by the door ?

12-30-06, 01:07 AM
the cluster and dash lights (Dimming lights) will not light up now.
The park lights, dome and door switch lights work!

ALSO!!! when the park light is on, the fuel computer goes out!

I will try disconnecting the alarm wire tomorrow! thats a good point!

12-30-06, 01:14 AM
check one more thing. under the hood fuse box
fuse # 46

12-30-06, 01:15 AM
Fuse box on the Right??

I checked the hood location and drivers dash when u open the door.
Am I missing another location? I hope so!!!

12-30-06, 01:31 AM
I will check #46 in the morn, thx!
From the diagram, It looks like the mirrior switch shares the same ground as the interior dimming lights. By chance, does the fuel computer share the same ground?
Thx again

12-30-06, 01:43 AM
I'll try to get some more info for you too

12-31-06, 02:57 PM
Which one is #46. My fuse box isn't numbered.
Could have I blown the dimmer dial?!?

12-31-06, 03:31 PM
possibly you damaged
the switch
RADIO Fuse #46
Radio and Instrument Cluster


12-31-06, 06:51 PM
46 is good! They all are good. I'm going to test the dimmer next.

12-31-06, 06:53 PM
By the way is the HDLP Relay the spot where I could add a diode in order to get my low beams to stay on when I'm using my highbeams?

12-31-06, 07:09 PM
Check the ILLUM fuse in the left hand IP fuse block.
Otherwise you could have fried the potentiometer in the headlamp switch.

I agree, remove the wiring you have installed and be sure what's happening before you try to move forward.

01-01-07, 01:13 AM
what is the potentiometer?
I'm guessing it has to do with the dimming dial?
Would i be able to replace or fix it without replacing the whole dial (ie replace resistor).
I have an electrical backgroung, esp with car audio, electronics...etc


01-01-07, 09:28 AM
The potentiometer or "pot" is a variable resistor that controls voltage output to the interior lamps, if it was turned to full bright and you applied a ground to the circuit you could have burned up the circuitry inside.
(or if it was turned dim and you applied a voltage)
It's serviced by replacing the headlamp switch if it's bad.

01-01-07, 05:35 PM
Thats exactly what it is.
I'm going to take apart the switch to see if it poss to fix, otherwise it's off to the stealership to buy one.
I was considering picking up one from a chev truck line. I could swap the guts for prob 1/3 of the price?!
the dealers up here sure like to take advantage of the Cadi name!!

01-01-07, 05:52 PM
possibly you damaged
the switch

I'm glad to hear it was just a switch and nothing else.
switch it self should not be to expensive

01-01-07, 06:45 PM
Some newer ones use a printed circuit looking thing with a carbon strip on it. If you accidentally put power or ground to the wrong circuit at the wrong time it will fry the carbon from where the brush is to where the other end of the circuit is. Ask me how I know ;) (just kidding, I think you could figure it out)
Not sure how much the headlamp switch is but it sounds like that's what happened.

01-01-07, 10:14 PM
GM Geek,
Could u post the Headlight/dimmer switch diagram?
I'm trying to trace it out and something is not making sense.
Please and thank you.

01-01-07, 10:26 PM

01-01-07, 10:31 PM


01-01-07, 10:34 PM
10 amp fuse shoud comtrol illumination
fuse box on the left side of your I/P

01-01-07, 11:21 PM
Thx, I think I got it.
It's the Pot(Cicurt board looking thing that controls the light intensity. If I jump it there, it illum fine.
Also, it has to do with the drivers info center, so thats prob why it cuts out when the park lights are on!
thx again!!

11-24-08, 09:55 PM
I'm having this problem as well, can tc3 or yourgmsolution give me a little help?

11-26-08, 01:11 PM
U need a new light switch. Details as in post #25

11-26-08, 01:24 PM
http://cgi.ebay.com/ebaymotors/Tahoe-head-light-switch-GMC-Suburban-Yukon-escalade_W0QQcmdZViewItemQQ_trkparmsZ72Q3a1205Q7c6 6Q3a4Q7c65Q3a12Q7c39Q3a1Q7c240Q3a1318QQ_trksidZp32 86Q2ec0Q2em14QQhashZitem180308723528QQitemZ1803087 23528QQptZMotorsQ5fCarQ5fTruckQ5fPartsQ5fAccessori es

Just replace this part?

11-27-08, 02:45 PM
Thats the one!

09-19-09, 06:41 PM
I have the same problem. Do i just need to replace the switch??

10-21-09, 05:37 AM
I have the same problem, as well. I replaced the switch and that didn't solve anything so I made a jumper to hard-wire 1, 4 & 10 on the switch harness when it gets dark. Since I work night shift, this is quite a pain but I've had this problem for 2+ years and nobody has been able to figure out the cause so I gave up.