The setup in my car is a JL 12w7 in a high output box powered by a JL 1000/1v2 slash amp. I am using my stock car battery and I did NOT do a big 3 upgrade.

This setup worked without any problems for a couple weeks. However, yesterday I was driving and I turned the head unit from volume 0 to 47 (max is 60) very quickly. There was a very bass heavy song on and I also had the air conditioning on. When the volume got up to 47 all these warning lights flashed on my dashboard. Keep in mind that I had played my system at that volume level almost every day for the past 2 weeks without issue. However, this particular time, I cranked the volume up pretty quick. The warning lights on the dashboard were the following:

-ABS Fault
-Brake light on
-Stabilitrak issue (either an error or saying it was off)
-Check Engine Light On
-Check Engine message on the display
-Contact Dealer with a red X flashing

Also, my gas gauge was all the way down on empty even though I had 3/4 tank of gas.

I pulled over and had the car towed to the dealership. They weren't able to look at it until Thursday morning. They looked at it all day and said they don't know what to do. They said that they had never encountered something like this before. They said that whenever they turn the car on, all the warning lights come on and the gas gauge and other gauges go to empty. They think it's an electrical problem and said they are going to start ripping my dash apart tomorrow to fix it.

I am pretty sure that this problem was caused by rapidly turning up the head unit quickly. My car's alternator puts out 130 amps not under load. And the JL 1000/1 is rated to take 90 amps at max (could be higher). So, if I had the AC going and I turned the head unit up quickly, could this have caused a voltage surge and messed up the electrical system?

Assuming the shop fixes all this (and hopefully doesn't charge me since my car is under warranty), what can I do to prevent this from happening again? Do I need to do the big 3 upgrade? I read online that you should do the big 3 upgrade if your amp pulls more than 800 watts RMS or if your headlights dim. My headlights dim and my amp pulls 1,000 watts RMS. Also, I read online that my stock battery is small. So, should I....

1. Do the big 3 upgrade?
2. Install a 2nd battery that is dry cell and can perform cranking
3. Upgrade my alternator?
4. Anything else?

Please let me know which of the above three items I should do to prevent this from happening again.

I got an estimate from a local shop and they want $200 for the labor and wires to do the big 3 upgrade. And they want $330 for a VMAX CT-1000 charge tank, and $90 PAC-200 battery isolator. It comes out to around $860 with tax and labor. Is this reasonable?

I think I might be OK with my alternator since it is putting out 130 amps. A dedicated battery for the amp and the big 3 upgrade might be enough. But I definitely don't want this to happen again after they fix the car. They don't even know how to fix the car at this point

Any ideas or advice?