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Non working dash / instruments panel illumination

11K views 22 replies 7 participants last post by  Gptb008 
#1 ·
Hi TrailVoy enthusiasts:

I installed LEDs replacing the eight OEM bulbs (dome lights, 2 each door) in my Envoy 2004, L6. Now my dash/instrument panel illumination is not working.

I did check the following fuses and they all are OK:
Under hood
#24
and all others

under the driver side rear seat
TBC2 fuse #7
TBC5 fuse #32
and all others.

I found blown-out and replaced fuse #4 under driver rear seat.

Instruments work well and radio illumination dims OK, it only the dash/instruments panel illumination that does not work.

What could be causing this problem?

Thanks, Ed
 
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#2 ·
Hi TrailVoy enthusiasts:

I installed LEDs replacing the eight OEM bulbs (dome lights, 2 each door) in my Envoy 2004, L6. Now my dash/instrument panel illumination is not working.

I did check the following fuses and they all are OK:
Under hood
#24
and all others

under the driver side rear seat
TBC2 fuse #7
TBC5 fuse #32
and all others.

I found blown-out and replaced fuse #4 under driver rear seat.

Instruments work well and radio illumination dims OK, it only the dash/instruments panel illumination that does not work.

What could be causing this problem?

Thanks, Ed
 
#3 ·
Ed, no need to double post for the same problem.:nono:

Apparently, your replacement of the interior light with LEDs may have caused your instrument lighting issue. Recommend also checking (with a meter preferably) rear panel fuses 31 and 40. Beyond that I don't know what else to check.
 
#5 ·
Thanks for replying... everything else works: dome lights, all gauges, radio, left/right turn lights, etc. Only panel illumination does not work. Being far from an expert, i tend to think that maybe panel illumination bulbs burned-out but... all of them? :confused:
 
#6 ·
It's remotely possible, but highly unlikely. Do you have a voltmeter handy that you can use to check voltage? First I would check for power on the wiring harness to the cluster. I wanna say it's a brown wire with a white stripe but I'd have to check... If there was power there, then there could be a problem with the bulbs (easy to fix if you can solder), or the cluster itself.

If there was no power at the harness, then you'd want to go back and check the fuses, or maybe some damaged wiring somewhere. :undecided
 
#13 ·
nice roadie. and for the guy with the leds.. did you put 470ohm 1/2 watt resistors on each bulb? there are other threads on here that tell more about it. no resistors will cause all the bulbs to blow. *happened to me*
Which one, there's two of us... :raspberry I can tell you though, that the size and type of resistor depends on the specs of the LED. Voltage and current specs is what you need to go off of. There are plenty of online resistor calculators you can plug numbers into, and it will tell you what you should use. :m2:
 
#14 ·
Wao, scary pictures... don't do that to me please. :bonk:

Well two things that i have to point out folks:
1. What is working?
a) Radio lights, turn on and dim ok.
b) Windows/power lock controls on door panels, illuminate and dim ok.
c) Gauges and DIC are working OK.

2. What is not working?
a) Instrument panel illumination, does not turn on.
b) A/C control panel illumination is not working, A/c works ok though.

Regarding the LEDs, they were not marked. I did not use any resistor or anything else, just installed them. I can remove them if needed to solve the other problems.

Based on the above details, i believe that it wont help if i take out the instrument panel since the A/C module is not illuminating neither.

Please continue to share your comments and suggestions. What can i do to resolve this?

Ed.
 
#15 ·
Regarding the LEDs, they were not marked. I did not use any resistor or anything else, just installed them. I can remove them if needed to solve the other problems.
Where did you buy them, and were they marketed as being for automotive use? If you just bought naked LEDs at Radio Shack or an electronic component store, the polarity of the LEDs is indicated in the length of the lead. One of its wires is longer than the other, and that's the anode, or the positive side. The cathode is shorter (sometimes the plastic case is molded with a flat on this side as well), and that one goes to ground. These sorts of LEDs cannot just be soldered into place without a resistor in series with either one leg or the other. And you have to put the anode on the positive terminal, which requires a meter before powering off the board. Sometimes, the cathode/ground side of a lamp socket is a square pad instead of round.
Based on the above details, i believe that it wont help if i take out the instrument panel since the A/C module is not illuminating neither.
The AC control module shares the lamp circuit with the instrument panel, but also the radio, transfer case control switch that you don't have, and the rear wiper control switch. I can't explain how your radio is staying on while these other lamps are dead.

Let us know about the source of your LEDs.
 
#16 ·
If, all you changed were the ceiling lights, you could not have blown a fuse for the instrument panel lights.

If other "night time driving" lights are working (like the window switch illumination), then check the position of the dash brightness rheostat. Do you have it turned down, or off?
 
#18 ·
Thanks for your replies guys!!! Please note that i double posted by a mistake and inadvertently. I am following only this thread, sorry about the confusion; the other tread can be deleted.

About my problem... What i installed was ebay item 180563700093, installed two on each door dome light, they are working OK.

During the installation of the leads, fuse #4 burned-out and i replaced it. I did not mess with anything else.

If the "the dash brightness rheostat" refers to the knob that dims the panel/radio/window/power locks/AC; that is dimming the radio and window/power lock controls so i guess it is OK.


So, considering what i mentioned that is working and not working:

what can be causing this problem?

Should i remove the led bulbs? (I do not want to deal with resistors or similar things).

Thanks, Ed
 
#19 ·
Thanks for your replies guys!!! Please note that i double posted by a mistake and inadvertently. I am following only this thread, sorry about the confusion; the other tread can be deleted.

About my problem... What i installed was ebay item , installed two on each door dome light, they are working OK.

During the installation of the leads, fuse #4 burned-out and i replaced it. I did not mess with anything else.

If the "the dash brightness rheostat" refers to the knob that dims the panel/radio/window/power locks/AC; that is dimming the radio and window/power lock controls so i guess it is OK.


So, considering what i mentioned that is working and not working:

what can be causing this problem?

Should i remove the led bulbs? (I do not want to deal with resistors or similar things).

Thanks, Ed
These types of LEDs come with the resistors built into them, so you don't have to deal with that aspect. Now the overhead lights light up properly right? You can try putting the stock bulbs back in and see if the HVAC and cluster illuminates like it's supposed to. If that solves the problem, then somethin in the way the LEDs were made had a problem. :confused:
 
#20 ·
Guys:

I did remove the LEDs, still no luck. "The roadie" and "Blckshdw" mentioned that i should check the following in the instrument panel cluster:

Instrument panel power:
Orange on pin A2 - on all the time by way of front fuse #24
Pink on B7, on with RUN/START by way of front fuse #22.

Ground:
Black on A5

Dimmable lamp control:
Brown/white stripe on pin A7

I will check on that as soon as it stops raining here :). Though the A/C panel lights and the steering wheel radio and cruise controls illumination
are not working either, there is still a remote possibility that all these bulbs were burned-out. As mentioned, controls in the driver door and radio
illuminates and dim OK though.

If not other suggestion, i will be checking on the instrument panel cluster.

Thanks all for the help, i appreciated.

Ed
 
#21 ·
Hi guys !!!

Good news... after taking a closer look to fuse #7 under the driver side passenger seat, i found that it was not making a good/firm contact, sometimes was working and sometimes it was not. I adjusted the connectors and that FIXED the problem. Now i have panel and A/C module illumination.

Thanks to this site and to its contributors (you guys!!!). :tiphat

Ed
 
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