My 95 Toyota Avalon xls just died--about 140K miles. A month ago the electrical system began been acting up insofar as the clock and temperature sensor displays began fading in and out--flashing dim. I didn't notice any other problems, and no fuses were at issue. Then, a few weeks later the radio/cassette began making loud buzzing sounds, then turned itself on and off several times. Over the next few days, it occasionally came on by itself (with a loud buzzing pop and hiss) and then after a few more times it died out fully. Again, no fuses were bad. Finally, the clock and temperature sensors finally stopped working about a week ago. NOW for the question.

I went outside today and after opening the doors remotely with the Toyota FOB, I tried to start the engine and the starter engaged for half a second and then everything died electrically, in an instant. No clicks, no lights, no nothing. The battery is new, so that shouldn't be the problem, and I am fairly experienced with batteries so I know how they work and fail. Any ideas? I see what look to be non-user accessible fuses? Behind the main fuse box, but it appears one would have to take the panel off. Is this worth a try? Are there fuses like that which control everything like a main disconnect? I hate to bring the car in if there is something I have a real chance of being able to attempt to fix on my own and if there were something like that it would probably be cheap. At this point, if I must have the vehicle towed to move it, but it is safe in my driveway. Anybody have any advice? Thanks in advance.

. Remove and fully charge the battery. You need to establish, for a fact, that the battery is good. AutoZone will do this for free, if you don't have a battery charger.

. Test all under dash and under hood fuses with a test light or multimeter:

https://www.askmehelpdesk.com/cars-t...tml#post252145

Possibility is the battery ground cable or loose connections at any battery termination point.

A bad alt can put a large parasitic draw on your new battery. From what you described in the events leading up to this, I'd have to say the diodes have gone bad in you alternator and it needs replacing.
I also agree with KISS.

The same thing happened to my 95 Avalon... What was the solution for you?

I agree with kitch about checking the alternator.
You'll need something along the lines of a lab scope to really see what I'm talking about here: if too much A/C is leaking out of the alternator, first, the battery doesn't like the taste of A/C, plus, sensative on-board electronics aren't fond of it either. Damage could result in virtually every electronic component in your car.
Have the electrical system properly diagnosed or your car could soon be a memory.