The CD / Radio audio unit in my AUII Fairmont isn't working anymore

No lights, no sound, nothing

any clues how to fix it?

cheers

may sound stupid but have u checked the fuse in the fusebox?

checked both fuses
both fine

what could be next?

Sounds like your going to need to pull that stereo out and have a look at the condition of the wiring behind it.
IF it was working, then all of a sudden its not working, start simple as mentioned earlier:

1) Check fuses in fuse box - (Radio Fuse + Accessories Fuse)
2) Check cables attached to battery, if anything sounds like it shorts when you touch it, you could have a loose cable.
3) Still not working? Start taking your dash apart...
Refer To: (documents.php?d=5)
Double check your wiring on the back side of the headunit with above reference.

If everything seems to be in order, get out some tools, you will need tape, side cutters, wire strippers (If you cant strip them with sidecutters).
Disconnect negative terminal of battery, Find your positive wire and your negative wire onto the headunit, cut them off, strip about 1cm of sheath away so you have a clean wire, find yourself an LED or a 12v globe of some description, connect to the + and - cables that were powering the headunit, it should be safe to hold the cables on there with your fingers, otherwise leave somewhere they wont touch the body of the car and go reconnect your battery.
Test those leads on the globe, if it lights up, your headunit is borked and time to replace it, if it doesnt light up, you have a bigger problem...
You may need to trace those wires back and check to see if one has broken somewhere, or has been damaged by contact to metal going through the firewall etc...

That's about the rundown of how I would tackle that problem, let us know if you have any further issues...

EDIT:
Just double checked that reference, it's not listed but you are looking for BLACK wire (Negative) and the YELLOW wire (+12v Constant voltage)
BE careful with the YELLOW wire, it has power running through it constantly even when the car is off, don't touch it on anything lol...
For safety when working with electrical systems, always disconnect your battery before hand...

It probably also goes without mentioning that if you are going to cut the cables, and intend on leaving the same headunit in there, try to cut with plenty of slack either end so that you have something easy to work with when reattaching the cables...
To reconnect the cables, either solder them together, or if you dont feel confident doing that, try to find some little "terminal blocks" you may have some lying around or pick one up from mitre10 or other hardware store, you can use the terminal block to just run a wire in each end and they clamp down in the middle, connecting said wires, no mess, no fuss
Always use the tape to insulate positive wires especially, I have seen a fairmont burn to the ground due to dodgy wiring (not mine), believe me its a heartbreaking and costly mistake.

it's working now!
geez

i just pulled out the fuses
and then put the fuses back in

then it worked again
odd... it must have been loose fuses?