-2008 Hummer H3 L5-
Climate Control Module (photo attached) back-lights not working. Otherwise module works perfectly. A/C function, Re-circulation function, and Rear defrost functions all work, just no back-lighting behind functions performed by turning the know.

Light Switch Assembly (photo attached) back-light not working. All functions are working normally, but no back-lighting.

4-Wheel drive mode selector assembly back-lighting not working

Both rear door window switches work, but no back-light.

I have replaced bulbs in the Climate Control and door switches to no avail.

Seems to be a common interior "illumination circuit" issue, not individual components. Is there a particular wire leading from the BCM that supplies the voltage for this illumination that I can trace through? Does not appear to be any fuse issues in the engine compartment fusebox.

Anyone have any thoughts or suggestions?
Thank so much!!!

 

You can replace the bulbs. Carefully open up. I put led in mine

 

Like I said, I've tried replacing the bulbs and they still do not illuminate which leads me to trying to find the source wire for the power supply to the backlight illumination. If new bulbs dont light the assembly, then there is an issue in the system supplying them. I've changed entire modules as well, the replacement module also didnt light. So has to be a wiring issue.

 

Let's start with simple things.

Do your gauges and radio dim when the dimmer wheel is moved?

Did your back lighting work before you replaced the bulbs?

 

The gauges do dim with the wheel control on the light switch assembly. The bulbs in the climate control assembly, light switch assembly, and door switches did not work before or after changing the bulbs which is what leads me to believe that it is an electrical issue. My H3 has an aftermarket stereo as well... (Sidenote)

 

Did you replace fuse 13 yet?

OK, I think we are getting somewhere now.

Did you install the aftermarket stereo? Does the dimmer wheel work on that stereo?

First, I would remove the center panel and unplug the stereo and see if the illumination wire for the stereo has power. Make sure the aftermarket stereo illumination and dimmer wires are connected to the proper wires conning from your H3.

If the wiring from the aftermarket stereo is incorrectly hooked up that can play games with your vehicles illumination. I have seen this a few times.

 

I will investigate those and get back with you TAINTER.

 

OK TAINTER... sorry for the delay. I've since reinstalled the factory unit. I only used quick disconnect adapter harnesses to install the aftermarket, so no butchering of the factory harness took place. The entire center console (4 wheel drive control assembly, radio, climate control assembly) are all back to original spec. The radio does not seem to have backlighting. I can only see the radio station that it is tuned to or the clock. It has had no effect on the lack of backlighting on the light switch assembly or any of the components listed above in the center console.

 

Did you replace fuse 13 yet?

If the fuse is good and you still Don have back lights it has to be a short. Just not sure where to look.

 

Fuse 13 is intact