Hello, I'm Jason. I will do my best to answer your question quickly and accurately using the information you have provided.
Ok, let's start with the simple, before moving onto the more complex
have you had the battery tested?
I have not. It has been starting strong all along so I really never thought it would be an issue. Typically one would see a dimming or hear a tick, no?
sometimes batteries do die very gradually....
however, in cases where a cell "sulfates" or essentially goes bad, the battery can quickly go from 12v to 0v
and your car being an 06....likely has the original battery
6+ years is about the lifespan of the Audi batteries
Wouldn't there be something indicating? There is really nothing. Lights sounds. Ticking. fuel pump.
if the battery falls under 4-5 volts, nope, no sign of life at all from the car.
obviously, I have to assume that the battery terminal clamps are not loose
but that's easy enough to determine
I was driving it last night and in fact was shopping with the wife and started several times.
it just seems odd to me that it would go from strong start to nothing.
I checked the terminals and they are tight
as most batteries fail gradually, yes I agree that it's odd, however in the case of internal cell failure, it can happen in a relative instant
voltmeter would confirm this
Unfortunately I have a teenage son and tools are missing.
LOL....sorry, but I understand
do you at least have a 10mm wrench, and 13mm socket with extension and ratchet?
It would be a relay? Probably not fuse as it is too general a problem.
neither a fuse nor relay would knock out everything you list at the same time
Interesting? Security system? No mods to the car everything is stock.
Are there and caveats in replacing the battery?
security system will shut the car down after running for 2 seconds, but all electrical accessories, AND the starter will function
battery is easy. Remove 13mm bolt on passenger side....
remove negative clamp first
reinstall in reverse order, installing positive clamp first
Will battery replacement have affect on security system, settings, computer etc.?
likely just the clock and date
radio should be fine, as it has it's own memory, not battery related
Thats an easy fix. Thanks. Recommended battery? Anything special?
let me look up the group number
So any brand with those specs?
well, I prefer the Interstate brand, but the size/group number, if you go with a different brand is group 48
I will look for Interstate and do the replacement with fingures crossed. With all the drivers in this house I need my car running at all times. Thanks again AudiDoc.
Sorry that was "fingers crossed"
glad to help!
I'm sure it will be fine