I would offer, I just did this to mine, fixed it perfect for about a week and now the fading is starting again so I'm not sure I could guarantee perfection haha
Duuuude, I am so happy I stumbled upon this post. Fixed mine today and it looks perfect! What's funny is that I'm an electronics technician by trade, and specialize in microminiature electronic repair...so I feel kind of dumb for not checking the IC chip to begin with, lol. Either way, thanks for posting!WARNING: do not attempt to do this yourself if you have no prior experience with fixing pcbs/electronic components. Ask a professional for help.
I did not diagnose the problem. All the credit goes to the great people on Polish Mazda forum: Forum MazdaSpeed
The issue is the SMT (surface mounted technology) microchip that has lost its connection to the pcb.
Remove and disassemble the display:
Unsolder and remove the metal frame:
Release tension on all pins and very carefully unbend the LCD screen to remove the black plastic housing:
Unsolder smaller pcb with LEDs:
This is the microchip. Silicon that covers it needs to be carefully removed. Use a small knife and soft metal brush.
Once you get to the microchip you need to refloat all it connections. You will need a good solder gun like Weller or similar.
Inspect for any shortened circuits / bad solders under the magnifying glass or microscope:
Assemble and test (you can also test the main board with lcd by itself without the leds and other components):