What is the cause of this?

The car came with the ly undersized "racing battery" and aftermarket adapter plate which would die within a few days of being off the trickle charger. I finally got fed up with this and replaced it with a brand new full sized battery as the 20 lbs weight savings is negligible for daily driving. After about 2 weeks the battery was completely dead. I'm pretty sure it killed the battery as bringing it back to green on the battery tender now takes about 4-5 days and sometimes it won't even get there and the battery tender just flashes red and green the way it does for a defective battery. This is infuriating to fry a brand new battery.

What is the culprit on these vehicles for this? Where is the problem fuse that has current gong through it with the ignition off?

Even more infuriating is after bringing the car back to life, it seems everything is dead in this car:

1. Radio won't turn on
2. Nav screen won't come up
3. Passenger window won't open at all
4. Passenger airbag off warning permanently stuck on.

All of this from a low voltage condition? I would expect this if the car got hit by lightning, but holy crap!

 

Are you 100% sure you got the right battery? I ask because some of the symptoms are those which happen when a battery is underpowered. I would also check your fuses one by one to see if anything has popped.....

 

It's a lot bigger than the one that was in there, that's for sure. It barely fits in the receptacle so I'm pretty sure it's the correct size. No issues starting the car.
Oh, and now I get a "service alarm system" warning that i have to clear from the display every time.

Oh, and the adjustable lumbar support no longer works. It's like every electrical component in the car decided to nope out in glorious British sports car fashion due to a simple battery voltage decline to 0.

 

Coupe or Roadster? A failed convertible roof module can cause all sorts of issues when they go south. The service alarm warning could be a failing battery in the alarm module. One or the other of those could be preventing the car from going to sleep when the key is off.

 

Coupe.

I pulled the battery out tonight. It's a September 24 date code. H8 size, 850 CCA. I am trying to bench charge it but will try to return it and try a new battery.

Cycling the battery fixed the window problem but the audio system and nav still won't turn on.

 

on some of my other vehicles, i disconnect both battery cables and touch them together for about 60 seconds and it will reset car modules... I've done this on my Ram, Mercedes and couple of BMW's... never had to do it with my Aston. they are finicky when comes to electronics.

 

There is a battery disconnect that triggers if the battery is too low. On the 2007 I believe it’s behind the passenger seat. Try resetting that .

 

I replaced the battery and checked all the fuses. The radio still won't power on (It says Vantage audio for about a second then turns off) and the NAV won't open. This is a coupe, so no roof module.

Searching forums, it sounds like this happens when a module on the MOST fiber optic network fails. I am guessing something got fried when jumping the battery at some point.

I am at a loss as to how and track this problem down and fix it. Is there a way to scan the modules to find out where the problem is? Is there a process of elimination? I am not even sure how to get to the audio amplifier. I started ripping up the carpet in the trunk and stripped out one of those large screws and decided to be a bit more methodical about this.

Ideas?

 

I just faced a similar issue with my 2015 V8V although in the end my problem was just a dead cell in the battery dropping the voltage to about 11V. Things went south from there. A new battery solved everything, but yes a lot of stuff needed to be reset.
When fixed, At least on my car dropping the windows and holding down for three seconds and then raising all the way and holding up for three seconds fixed those issues. Next you have to work the seats to all the extremes and hold for 2-3 seconds. Sometimes the forward will not work, but tilting the seat all the way back starts the seat moving forward allowing the extremes to be reached.

Ok, back to what I would suggest. It sucks but you must have a perfect battery. Disconnect the new battery. Next attach a jumper pack to the plus and minus either at the battery leads or the emergency location in the engine bay. Drop the windows all the way and move the seats all the way forward and tilt forwards so you have access to the rear shelf area through the windows.

You will need or have to borrow a clamp multimeter. That can measure both voltage and current.
Disconnect the jumper pack and reconnect the new absolutely fully charged battery. You should hear all sorts of clicks and whirs as things power up. Measure the current draw on the battery with the clamp meter on either the positive or negative battery lead, it does not matter. If after a minute or so there is more than a few amps then there is a real problem. If you close the doors and walk away for 20 minutes and then read the current by reaching through the window to reset the meter and it is more than an amp you certainly have a problem. If the draw is less than an amp, it was probably the battery all along.
Obviously, if you have a Foxwell or similar true AM OBD code reader you can do a module health check which may reveal the culprit. If not, you will have to pull and replace each fuse in turn in every fuse box and see if you can identify the culprit sneak high current draw. With the car asleep, the total draw should be a few hundred milliamps. If you find one circuit drawing much more than that, bingo. Of course, there may be more than one module off that fuse.

Two final things. I believe that the alarm modules are an expensive sort of limited life component. Search on this forum for symptoms of a dead one. It may be excessive current draw.

Secondly, don’t skimp on a fully charged new battery. If the battery is the trouble in the end you will chase your tail for hours.

Philip