Help with Odd Electrical Problems '03 Aero

Hi Y'all. I have an '03 9-5 Aero with 240K miles. The car runs excellent, but just lately I experienced an odd series of events which all happened right around the same time. Specifically, the button to open the fuel door stopped working, the power seats will not move, and the A/C fan does not blow. There is heat at the vents, but no blower at all.
The issue with the fan was the first thing I noticed and it didnt fail all at once. At first, the blower would not come on until the car had been on the road at speed for 10-15 minutes. Then one day it just stopped coming on at all. Also, I get no heat at the vents unless the car is moving at speed. If sitting at idle, there is no heat.
Within a few days of the fan issue, I discovered that the button to open the fuel door wasn't working, and my power seats are frozen. I checked the fuses and swapped out the relay, as I understood that the power seats and the fuel door are on the same relay, but no joy. I have the WIS on my computer, and have tried to make some headway with that but can't seem to get anywhere. I did hook the car up to a regular scanner, not a Tech 2, but no codes except minor evap leak, so that's good at least. I am wondering if this could all be caused by the alternator going bad. The battery is less than a year old and has started the car without fail in temperatures well below zero. All the interior and exterior lights are working and bright and there are no other symptoms that I know of - yet. But I would be grateful if anyone could give me some leads on what could be the problem. Could it be bad grounds? Bad alternator? Where should I start in trying to pin this down? Any help would be appreciated. I just don't want to be on the road and suddenly have other electrical issues possibly more severe come up to leave me stranded. Im fairly handy and have done alot of my own repairs. Oh, and I recently swapped the heater core bypass valve because of minor coolant leak but no joy with that either. Could coolant be leaking on something to cause a short? Thanks in advance for any ideas or suggestions.

Blower fans break, air door motors break, power seats break and fuel doors break too. All of these different things happen at any given time and the odds of them all happening at the same time and not being related to the body control module are darn slim. This little black box can cause some flaky problems when your voltage "browns down" and your best bet to fix without a Tech 2 is disconnect the battery to reset everything and make sure it has a good charge when you reconnect, if this fixes your problem great. If it doesn't then check your alternator, your ground points and check around for someone with a Tech 2 and TIS because you can't clear bus errors or replace a BCM without one.

Thanks so much for your reply. I am going to disconnect the battery today. Hopefully that does the trick. I did have an issue with the grounds a couple years back. Cleaned them up and all was well. May be time to do so again. Sure wouldn't hurt. But...if I install a new DICE, will the car still be driveable? I have a few local shops that have a Tech 2 so no problem there.
Also, there is one possible additional piece of the puzzle. I discovered this weekend that someone had hit my front bumper and smashed out my foglight. The damage to the bumper wasn't too bad and I repaired it with plastic Weld. But, could the smashed foglight have caused a short that would effect the components that are at issue? Thanks again for your response.

I have a local shop that has a control module for a 2003 saab 9-5 but it is not from an Aero. Will it work in my Aero once programmed with the Tech 2?

Fill in the blanks and find a part near you Car-Part.com--Used Auto Parts Market

Thanks. That will be very useful in future. I'm lucky in that I have a local salvage yard which has an '03 9-5 on the lot with plenty of good parts.