Every car brand is different but there can be similarities among models and years for a given brand. I'm most familiar with GM, Ford, and Chrysler products because those are the radios I used to repair for dealers, but GM and Ford selfishly locked up access to their radio service manuals so they could grossly over-charge car owners through their two authorized repair centers. As a result, I haven't been able to keep up with all the new technology.
What I CAN share is beginning with some 2002 or 2003 GM trucks, they cleverly built in the Body Computer into the radio so you couldn't replace it with a nice aftermarket radio. In response, the aftermarket industry came up with radio relocation kits. Those allowed you to mount the original radio in the trunk or under the seat to keep the chime, cruise control, and power window and lock functions, but you could connect the speakers to the new radio.
On GM and Ford radios, if it does not use a remote-mounted amplifier, it can't use one, and if it is used with an amp, it will only work with an amp. In effect, the final amplifier stage is either inside the radio or mounted somewhere else, and you have to replace with what you had.
All Chrysler radios put out speaker-level output and can be used with or without an amp. (That's a CHRYSLER amp, not some aftermarket pile). Chrysler amps do not increase volume or power. They only modify tone conditioning for the shape of the vehicle.
My reason for sharing these things is because they're the types of things you have to consider when replacing a radio. Years ago a "professional radio installer" was anyone who did it for his boss at a business. All you needed to qualify for that title was to be able to connect wires and build mounting brackets. I suspect today they have a source for some type of training to know how to handle all these designed-in problems in newer cars. What I would do with yours first is to remove and disconnect the radio, then see if there is anything else that doesn't work. If, for example, you find you have no dash lights, chime, heater control, or a warning light turns on, you can inquire at the dealership, but for the best answers I would visit some stereo installer's web sites. Saab is related to GM, and GM is one of the least customer-friendly manufacturers in the world. The people at the dealership, (if they even know), won't be likely to give up any helpful answers. Also, they are trained to diagnose and repair GM products and likely won't have training or knowledge of anything else.
Be aware too that on some cars, GM and VW in particular, if you disconnect the radio or disconnect the battery, the radio will go into a lock mode, and you'll have to visit the dealer to get it unlocked. They sure don't do that for free. I've been told that if you try to guess and enter three wrong codes on some VW radios, it will go into a permanently-locked condition and all you can do is throw it away. I can't say for sure if that's true, but given their many customer-unfriendly business practices, it wouldn't surprise me. The best is to know before you disconnect something. Also, if you will need to enter a code number to unlock the radio, there is usually a way to make the radio display that number before you disconnect it.
Tuesday, January 13th, 2015 AT 9:30 PM