2000 Lesabre Limited-dash controls go crazy

The dash display in my buick intermittently flashes all the lights and makes beeping electronic noises, the climate control engages then disengages. It seems like it has a mind of its own. This will happen out of the blue but especially if you are using the windows, or change the radio station, basically use any electronic component.
Recently the signal lights have also stopped working and the heat doesnt engage at all, the beeping and intermittent climate control was bearable but I dont want to drive without signal lights.
I am assuming it is all related, what could be the problem?

The dash display in my buick intermittently flashes all the lights and makes beeping electronic noises, the climate control engages then disengages. It seems like it has a mind of its own. This will happen out of the blue but especially if you are using the windows, or change the radio station, basically use any electronic component.
Recently the signal lights have also stopped working and the heat doesnt engage at all, the beeping and intermittent climate control was bearable but I dont want to drive without signal lights.
I am assuming it is all related, what could be the problem?

How's the battery condition? I believe, again believe, I read someone with really weird symptoms that were the result of a battery producing voltage lower than the computer systems needed.

Else, be sure the ground cable for the battery on the floor pan is getting a really good ground connection. Check the bolts holding down various fuse blocks to be sure they're tight and giving a good connection.

My bet's on the defective, worn-out battery.

The battery was changed last year, so it cannot be faulty. The problem started before it was changed and continued after it was changed, that leads me to believe the problem is more than the battery.
Have you heard of anything like this happening to other GM's.

Have you done any troubleshooting? Like checking fuses and any 12 volts related to the accessories circuits? About the only thing I see common would be a bad ignition switch based on your symptoms.

I have a 2001 Buick Le Sabre.. and I also experience the flashing dash board lights and the check engine light and just about every light coming on. Started when I used the left turn signal. Car would stall. Now I tried not using the turned signals ( both) so I can get home.. before it started getting possessed on me.lol Well, I had car checked out ..turned out battery wasnt grounded. and it needed the turn signal module switched out. Thats located on a fuse box located on the left drivers side. it took two mechanics to figure that one out.. Oh I ended by a new battery..solely because it was ready for it.. Good luck.. if you get this problem..