1997 Toyota Corolla DX: Power Window/Lock problem

I own a pre-owned 1997 Toyota Corolla DX with 120k miles on it.

It was 4500USD$ from the dealer (talked them down from 5999USD$).



Anyways, on to the point.



When I first test-drived the car, the back-left window wouldn’t work via power switch on the drivers control, where the driver can lock doors, lock windows, open/close any door window. A friend “fixed” it by trying to open it while in the back seat.



Then, a month later, I installed new speakers due to the stock ones being blown out, and a 400Watt amp, along with sub woofers. Now, I don’t go blasting my music around town or anything, I usually do it on my long drives to my house (5 miles out in the woods) so don’t go thinking I’m just another annoying person with a loud car.



The day of this installation (“Professionally” installed by Santa Cruz Sound Garden) all my windows either lost power, or broke. No window rolls down, or up, or even makes a sound.

It’s not only broken on my driver control panel (stated above), but all doors now cannot control the windows, and are (hopefully not) forever stuck in the up position.

As if that wasn’t enough, the master lock (lock all doors) on the driver side, does not work, while the passenger side master lock works.

My first though: Fuses.

I checked EVERY fuse I could find (kick panels and under the hood) and every fuse is unblown.

My question is, where should I look next?

I was told the motors could have failed, but all at once on the same day?

Or that the sub-woofers demand power and reject power to the power windows.

I’m trying to save money, so taking it to a shop is my last option.

The day of this installation (“Professionally” installed by Santa Cruz Sound Garden) all my windows either lost power, or broke.

Well I would guess the professional install was not as professional as it should have been. It should be up them to figure this out and correct it, not you. Did anyone suggest that you might want to beef up your charging system when you added this amp?

I was told 400 Watts isn’t very much, and that my stock alternator could handle it fine.
Sense I don’t know much about installing subwoofers, I wouldn’t know if they messed with the wiring or anything.

so, did you take it back to these Professional Installers? Have them remove the subwoofer and get everything back the way it was. Then find a different installer.

What if they do that, and the windows still don’t work?
Let’s brainstorm other ideas then the installers fault. I’ve gone over that myself MANY times.