This is mainly for Naki pile of radios but its also a general idea on what brakes and how to fix it.
40 radio alpine AJ9200R can be bench tested, no need to have it plugged in the car all the time. To power it up connect 12V as per schematics below(12V and radio memory pin, next to it) and ground to the back of the radio(anywhere to case or bolt at the back). Speaker can also be connected and tested to each output.(all outer pins, each side +/-)
Top row from left to right 6 5 4 _ _ 3 2 1
Bottom row left to right 14 13 12 11 10 9 8 7
Top line '91 / '92 MY showing wire colour and service
[Beneath the equivalent '93 / '94MY wiring] with obvious exceptions noted:-
1 - Red/white - LH front door speaker
[Slate/purple - LH front bass + LH front tweeter]
2 - Red/brown - LH rear door speaker
[Slate/red - LH front bass + LH front tweeter]
3 - Red/green - Common LH front & rear door speakers
4 - Light Green/black - Aerial via CPU
[Light Green/black - Aerial via CPU (pre- VIN 687219)]
5 - Red/light green - LH bass speaker
[Black/slate - LH rear bass + LH rear tweeter]
6 - Red/purple - LH bass speaker
[Pink/purple - LH rear bass + LH rear tweeter]
7 - Red/brown - RH front door speaker
[Slate/pink - RH front bass + RH front tweeter]
8 - Pink/yellow - RH rear door speaker
[Slate/orange - RH front bass + RH front tweeter]
9 - Pink/light green - Common, RH front and rear door speakers
[Not used (Purple/orange - telephone mute '94 MY)]
10 - Light green/orange - Ignition switched power
[Light Green/orange - Ignition switched power]
11 - Brown/white - Radio memory
[Brown/red - Radio memory]
12 - Red/green - Radio illumination
[Red/light green - centre console clock]
13 - Pink/red - RH bass speaker
[Black/white - RH rear bass + RH rear tweeter]
14 - Pink/orange - RH bass speaker
[Pink/green - RH rear bass + RH rear tweeter]
Here is another tip I found on internet recently:
Here is links configuration for car radio Jaguar AJ-9200R(Alpine)
1 2* 3 4* 5* 6
= code 2413
Apparently if you solder these(*), the above code should work fine. 300 radio is different, it comes with basic memory chip which can be easily read to find the code. Happy to help if anyone has any problems with these.
Radio generally fail in two ways, either a little 8-leg smd chip fails in which case nothing absolutely can be heard out of the speakers but other than that radio works fine.
The chip in question is on the left side, just in front of the white plug with white and yellow wires
Other component that brakes is one or both amplifiers. These are big square components mounted and screwed to the back of the radio. If one side of the speakers fails and other work then one of these failed. Any werid noises with good speakers connected or volume significantly lower than normally out of the speakers will mean this chip is shot.
The components in question are at the bottom of the above pic on each side.
Both the 8-leg smd chip and amps are easy to source and cheap to buy so well worth doing.
For the display issues - best to go to Mark topic: viewtopic.php?f=25&t=7436
Other than these issues there radios are build to last forever so never bin a radio even if its partially broken!