Hello, I had a same problem with my Yukon 2004.
The problem started intermittently and then became permanent within a month. The whole Instrument Panel (IP) dead...no gauges, no warnings, no cruise control lights... Just backlights ON, turn signals and check engine light working.
No matter how much I tapped on the dashboard, bang on the panel viewing glass, press the reset knob... it continued to be dead...I checked all the fuses and all were OK. I checked the Ignition switch by gently shaking it while the car was ON, Nothing worked... I was reading the solutions on the internet and some IP rebuild sites mentioned about this exact problem and they offered to fix it by sending them the IP and they will fix the problem by re-buiding the Instrument Panel. This gave me a strong clue that it has to be the fault within the IP....
Finally, I solved it for me. Here's what I did:
1. Took out the Instrument Panel. remember and note down the orientation of the plug... Disassemble the IP. There're a lot of videos on youtube on how to do it. I took care of the needle positions... as mentioned in the videos!
2. Just took the Circuit Board (see image) and hook it up back in the harness plug. NOTE that with only bare circuit board in my hand and connection pins bare without any slot for plug, the plug might connect both order (Up & down). so i made sure that I plugged it in the proper way, for me the grey part of the harness plug stayed on TOP.
3. With ignition in "ON" (I actually started the car) I gently pressed the circuit board components (mainly rectangle resistors with numbers like 511, 240...etc..) with a non metallic object (I used the eraser side of a pencil). Within seconds I found the culprit resistor. (The panel came to life briefly by pressing the resistors 210..see small red circle in the pics) These resistors get pretty warm during operation and over time the solder develops cracks and hence intermittent loss of continuity which becomes permanent over time. In my case they were the 2 resistors marked 210 (see picture with red circles).
4. I Re-soldered the two ends of these resistors with a soldering iron with a good quality soldering iron with a pointed head and good quality solder. I have limited experience of the soldering process. My soldering didn't look clean (Sucks...Yukk!!) like original but it did the job. All you need is continuity to the Printed Circuit Board (PCB). I took care not to overheat the resisters or circuit board by soldering iron.
5. I also re-soldered few other resistors as mentioned on various other websites. (see picture with red circles)
6. Finally I took the bare circuit board to the car and connected the harness plug. Turned the ignition ON...nothing happened...still dead... then i started the car and the whole circuit board came to life like a charm!!! (see pic)
7. I Reassembled the whole IP and put it back in the car... Fairly easy process! The IP works like a new born baby. The only thing is the speedometer needle that shows 2-3 kms less than actual speed when checked on google maps! I will readjust it by opening it again and readjusting the needle position over the next weekend. Even the PRND321 and the DIC messages are brighter now! I think something to do with re-soldering the other resisters made the connection conductivity better!
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So that's all friends! the above is a narrative of what I did to solve my dead IP problem. The above is to give you a better understanding of the problem.
Disclaimer: the above is only an explanation of my car problem as I "saw" it and as I "solved" it. It may NOT work for you...your IP can be entirely different from that of mine...You might develop some other problem while you solve this problem. You might destroy your IP while re-soldering or completely brick your IP......I am not compelling you to try this...I am just narrating my experience!!
You people are mature and know what you are doing!
