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2004 gmc envoy_sle_xuv
85 Posts
Discussion Starter #1
Going to try this again.... Uploaded pictures to the forum this time!

Well, trying to give back to the TV community. Here is my tutorial on how to replace or repair burnt out stereo lights behind the buttons on the GM radio or CD player in your TV. Some radios might be slightly different, this exact radio in the pictures came out of a 2005 Colorado.

Here is what I was starting with (notice the lack of lights in the left corner of the CD slot, the 3/4 button, the 5/6 button and the Band/CD AUX button)


The supplies you will need:

- Needle Nose Pliers
- Small flat head screwdriver
- Solder Iron (and solder)
- Light bulbs from Radio Shack
- Exacto Knife/Razor

There are two size of light bulbs behind the display/buttons. Most are pretty small and these are the bulbs that will replace those (comes in a pack of two for $1.69 or $1.99):


The larger bulbs go behind I believe the 1/2 button and the 5/6 button (comes one in each pack for $1.69). I could not find the EXACT bulbs I wanted at the Radio Shack near me, but these bulbs worked, just were a little more of a pain. If you can find a larger size bulb without the insulated wires attached, let me know and I will change this, make sure it is a 12v bulb and hour rating is high (I believe both of the small and large bulbs were rated at over 6,000 hrs, one was 10,000 hrs I believe).



1. Turn on car (and headlights) to make sure which bulbs are out. Remove radio. For quick reference you can find that information here:

2. Once you have the radio out, you need to pop off the top and bottom metal covers as seen below.


They just pop on. I first pried at this location to get enough of a gap that I could move over:


Next I slid the screwdriver in where there is the half circle and pried up. This pops off the corner, just do it to the other side and then it should pop right off (kind of slides into the front). Do the same thing to both the top and bottom:


3. Remove the Vol/Power knob, the Tune/Display knob and the Audio/P-Type knob. All of these just pull off, the Vol/Power and Tune/Display knobs will be two pieces (the outside spinning ring and the inside button).


4. Disconnect the wiring harness that go to the front display. Here is a picture of the one you need to remove on the top side (should just pull off, this area was tight and I used the needle nose pliers to grab the wires and pull it out):


And the two your need to remove on the bottom side:


5. Remove the front black cover. To do this there are two tabs on each side (top, side, bottom, side so a total of 8 tabs). I seemed to find it easiest to start on either the top or bottom and just work my way around.


6. Take the needle nose pliers and remove the 7 bolts that hold the circuit board to the front panel. If you have a socket small enough, go for that, but it was too small for any of my sockets so I just used my needle nose pliers... Kind of a pain if you have to do it that way, but it can be done. Once you remove them all, be careful and do not just pull it off, when you have it loose, tip it so the buttons face down so you do not spill/lose them all over the place.


7. Locate the location of the burnt out lights on the circuit board. If it is a small light, you will melt the solder and pull it out from the front of the board. If it is the larger light with the black mount, you will push it through to the back of the board. Some of the connections have a clear coating of silicone or something. This will easily melt with the solder iron to allow you to get to the solder connection.

8. SMALL BULBS: Once you have the bulb out, disassemble it. You can carefully pull the blue "condom" off the bulb and then slide the bulb out of the base:



9. Take one of the new bulbs


And cut the "legs" so they are as long as the ones on the old bulb.


Slide it into the base (do not put the "condom" on yet).


10. Resolder the bulb into the circuit board. I had to "walk" the bulbs in (melt solder on one side and slide the bulb a tad, do the same to the other side, and keep going back and forth to get it all the way in). You could avoid this if you cleaned up all the solder and made sure the holes were clear. Make sure the solder connection is good and add solder if you need to.


11. Slide the "condom" back on the light:


12. LARGE BULBS: I forgot to take pictures of the larger bulbs, but will try and walk you through what I did. After you remove the black based bulbs and pull the bulbs out (they just slide out of the base), you can see that the bulbs I referenced above are slightly longer. This does not really affect anything. You will have to prep the new bulb. If you can find the larger bulb without the insulated wires and just with the leads/legs like the small ones, that would be the way to go. If you use the bulbs I pictured above, you will have to use the exacto knife to slice the outside clear plastic that goes around the base of the bulb and then wiring connections. You will then notice a hard "gel" that insulated the bulb to wire connections. The best way I found to remove this it to just melt it off with the solder iron and then clean it off the solder iron. This will stink, but will work. At the same time, you can melt the solder that holds the wires to the bulbs and pull the wires off. The leads/legs on the bulb are not quite as long as the ones on the old bulb (and part of the reason I say if you can find the other bulbs to do it), but they are just long enough to stick out of the sides of the black base. Slide the bulb and base back into the board and resolder, making sure that there is a solder to lead/leg connection.

If you want to test your lights and see if they now work without completely putting the radio back together, just put the circuit board on the front of the HU and plug back in the 3 wire harnesses you disconnected in step 4 and plug the HU back into the car with the headlights on and key turned to a position that the radio would be on.

13. Reassemble in reverse order. No real secrets here.

14. Hopefully when you are done your radio should now look like this again (minus it being locked because I have not changed the VIN in this radio yet):


2005 chevy trailblazer_ls
3 Posts
2005 Trailblazer radio bulb replacement

Did you ever find the "EXACT" replacement bulbs you described? AS a newbie, I would be best off if I could easily compare and make sure I'm putting the right bulb in the right place. You mention a black base, but I don't see that in any of the pics. Any help that would keep me from destroying my radio would be greatly appreciated!

You description is extremely helpful and is the best I could find in helping try to fix the problem. Once replaced, do the other bulbs start failing quickly?

Thanks in advance,


non_gmt360 trailblazer_lt_ext
241 Posts
Bbbubba.. If your going to fix the bulbs, you might as well as replace them with LEDs.. They last longer, and you can go with a diff. Color. If you want help, or to see more awesome ideas with leds, check out the led mod thread over at: g m t n a t i o n . c o m ( no spaces of course) that is where I learned all about how to mod my truck. This place is great for archived material, but for real answers, that place is the place to go.


2003 chevy trailblazer_ltz
69 Posts
Changing Bulbs to 12 Volts Bulbs

Hi, I want to share my experience with Radio bulbs trailblazer 2003.

After changing the buttons for some new, some lighting bulbs stopped working, then I changed for 12 volts bulbs 12 and when I connected the radio these bulbs little lit, then I removed them and I installed 6 volt bulbs and the same result, so very little lighting .

1. I discovered that on my radio bulbs are connected in series of 3 bulbs , as I show in the circles of different colors, there are 5 sets series of 3 bulbs and a series of 2 bulbs that are the volume and tune for a total of 17 bulbs.

2. This is the reason that putting bulbs 12 volt and 6 volt bulbs with not light intensity.
3. The solution, put wires to each bulb operates at 12 volts and thus left with very good lighting.
4. The connector radio show which pin is gnd and wich is dimmer signal that rises to 12 volts.
5.the gray with black stripe wires are connected to GND, the grays are lighting 12 volt signal from the dimmer.

There is only one modificaction ans it is Simply cut a track on the board that is joining the volume bulbs and tune.

One of the photos shows the result with 12 volts bulbs without the jumper wires, one illuminated much less than the other 2 this not enough current drain.

I hope this pain Head and Neck save them, because in my radio, original bulbs were not 12 volts.

Annex final picture of how it turned the radio with strong lighting with 12 volt bulbs 20150428_072608.jpg


Modificacion en tarjeta.jpg

Radio Connector.jpg

2003 chevy trailblazer_ls
19 Posts
This guy in the vid link provided talks about "Grain of Wheat" 3mm and 4mm 12v bulbs... all of which are available on ebay. The blue bulb covers are also available on ebay for each size. The guy had problems getting the 4mm blue covers off his bulbs to move them over to the new bulbs. They basically looked dry rotted from the bulb heat.

Note that the 4mm covers will also work on the 4.7mm bulbs in the cluster if you want to try a slightly less yellow output from a standard bulb replacement. I have everything on order to R&R my radio and cluster burned out bulbs. Heck, I even found a brand new radio face that includes all new buttons and blue lexan cover for the digital display on ebay.

I thought about LEDS... then thought how I'd have replace everything lit in the cabin to get everything to match... to each his own :D
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