I have used quite a few hours trying to figure out how to replace my original car stereo with a new one I have bought. I though it would be worth mentioning what I have discovered.
(Most came from this forum! :-)
1 Removing the original Head Unit
I did not have the original brackets to remove the unit, so I used two steal wires (A hanger) which I bent to fit the holes in the player. Then pull out the unit. It should slide out quite easily. Then just disconnect the wires on the back.
2. Add the new player.
The new player should have / have adapter to the standard ISO Contacts. Connect to these as normal. You should also connect a "Amp Remote" contact to the gray cable which is located in a Yellow Mini-ISO Contact. This will control the Bose Amplifier. Without this, you will not have any sound. I know, because I did not :-) As far as I know, you will also need to switch wires 4 and 7 (Yellow and Red) on the ISO Contact, because the wires have been switched. These wires are for Continuous/Ignition power. If they are wrong, the player will still work when turning on the power, but it will not get power to the memory etc. when the ignition is off. I have not been able to verify this last (Due to that I need to connect the Amp Remote Wire first :-) , but i have read it several places, so I assume it is correct. The wiring for my new player also states that this might have to be done for some cars (I Bought a Sony Player where the ISO Adapter was included). You should also consider to buy a bracket for Alfa Romeo so it gets a "perfect fit" in the Dashboard. This would cost about 12-14EUR. I have found them in black and silver, where silver is the one matching my interior the best.
I hope this is off help to someone else, and that you find this information quicker than I did! :-)
I also would like to mention how to find your code for your old player, if you have lost it. I found it on a different post here, but I think it is worth mentioning more than once ;-)
Site for code generation tool:
Blaupunkt Calculator Fiat,Peugeout Service Manual free download,schematics,datasheets,eeprom bins,pcb,repair info for test equipment and electronics
Enter your serial number removing BP0 and 7th character:
578162 becomes 3782578162.