12v battery died for no reason

You have to look online or if you're an electrical engineer you know how to set up your test meter between the battery and the positive terminal or whatever it is or the battery and the negative terminal rather and just let it sit there and look at the milliamps that the battery's pulling with everything sitting there off The hatch closed and you can either have the meter running through the hatch the hatch won't kill the wires the gasket just closes around them and you can watch the display I can't remember the numbers but anything over like 50 milliamps or something like that is not good and then you can unplug fuses and see when that drops substantially and what is on that circuit that sort of thing.

 

how can a battery just suddenly die like that without any warning? It's the original battery.

You just answered your own question. An original 12vbattery in a 2008? 16 years is a pretty impressive run, you more than got your moneys' worth. Most 12v batteries are on borrowed time at the 5 year point.

 

Plus the fact that you got into an accident. The way batteries are built, any sudden jolts can short the positive and negative plates together. That's why off-road rigs tend to use the expensive spiral plated batteries.

Hope this helps......

I lost my 13 year old battery when a grandma back into my car in a parking lot. No damage to the car, except a scratch on the bumper - but a few days later, the battery was below 11VDC and wouldn't start the car.

 

wow, 16 years may be a record. the reason it died there instead of on your watch is because they leave the doors open and drain the battery.
you can't do that to a 16 year old battery, resuscitation is not possible.

 

best thing would be to take it for a load test. in the us, most auto parts stores will test it for free.
or you can buy a load tester, they are not too expensive:

ref=asc_df_B0BK7SHH82

 

100 Amp, 6/12V Battery Load Tester

IMHO, I wouldn't want that battery flopping around. You hit a speed bump or pothole that battery is going to be moving and wiggling your power cables loose.

 

Your car does not have SKS? no black button on the driver door handle or trunk garnish?
The sks model came with the bigger battery. The non-sks had a smaller battery. The mounting plate for the larger battery is about $30 from Toyota or about $5 from a salvage yard.