Summary of the information I have pulled together and is what I used to fix mine.
Hi all, I posted this as a seperate topic before being directed to this sticky (cheers Sprtstourer)
Just some additional steps to follow along with the excellent piccies on previous pages.
I hope this helps you guys, my air con unit would not light up the display when night driving (pain in the ****)
So here's a fix.
Instructions for repairing lighting behind climate display, read before commencing.
1. Remove ash tray. Ensure card is not in the card reader.
2. Pull out card reader it is only held in place with clips.
3. Pull out bottom of climate display, again it is only held in with clips.
4. Remove the 3 wiring plugs from the back of the unit, the top 2 connectors have lever clips pull these across the plugs as far as they will go to release the bottom one has a small catch push this in to release.
5. Now remove the coloured cover from the front, this is done by releasing the clips top and bottom with a knife or small screwdriver.
6. Now remove the inner front cover, again by releasing the clips the 2 large buttons will probably fall out. Be careful
with the glass screen as this is quit delicate.
7. Look at the top right hand of the printed circuit board you will see the resistor highlighted in the picture.
8. With a soldering iron re-solder both ends of the resistor, be careful not to leave the iron on for too long, it is also easier if a small amount of solder is applied to the tip of the iron prior to soldering the resistor.
9. Now rebuild the unit, make sure the plastic strip is in place and the glass display is lined up correctly before fitting inner cover, donít forget to fit the large buttons.
10. Re-fit coloured outer cover and re-fit to car, make sure that the wiring plugs are correctly fitted, Fit the top part of the display into the dash and then push the clips into place at the bottom.
11. Re-fit card reader and ash tray. Job done
This repair can be carried out with the unit still connected to the car but takes a lot more care.
Card reader requires fingers under both ends and a hard pull straight pull outward.
AC unit itself is easy to pull out if you press down the small steel springs immediatly behind the white clips seen under the base at each side.
Here is a picture of the bit that need soldering at both ends..