Audia889

Hi, I have a 2015 audi a8L 4.0T

on my last audi service, they said my battery needs replacing and it will cost $900.

I looked up online and battery cost is about $200 to $300.

my question#1 - how to test at home if my battery is good for another year or should I replace right away?

my 2nd question - which battery should I buy and how to tell if it will fit in my car? I am guessing there are different types of Audi a8 batteries. Autozone had 2015 audi a8L battery for $210.





thanks

jfrahm

You've posted in the forum for the older D2 A8 [now moved to the correct forum I see] but we use the same battery. I'm running an Advance Auto Platinum H9 and they have a lot of coupon savings, I think I paid $130-ish for an AGM battery from them. I do not think they'll ship to your home though.
An H9 from the Audi or VW dealer over the parts counter might not be too bad also, you might call VW and ask about a Touareg or Phaeton battery, or just ask the parts guy for an H9/Group 95R battery.

To test at home, assuming you have a battery charger and a voltmeter, is to check the battery voltage. It's hard to do this with the car 'asleep' though but you can tell us what the voltage is if you just probe the battery with the trunk open, car off. It'll be lower than a battery would show if you disconnected it from the car. If you disconnected it, you might see 12.7-12.8V for a really good battery and 12.3 for one that's pretty iffy. However in-circuit it might be closer to 12V.

Can you test the voltage? What's that voltage?

On my old 2001 I can trick the trunk latch with a bungee cord hook and let the car go back to sleep and then check the battery voltage again, to get closer to 12.5V can you do that?

Can you put a draw on the battery, like leave the headlights on, key on, for 5-10 minutes? If so what's the voltage then? Will the car start?

On my 2003 I discovered the battery was weak as it'd fail to start if I sat int he car, key on, engine off, and messed with the settings, etc for 5-10 min.

For our D2s most parts guys want to sell us H8 batteries, which fit loose in the car. No idea why they do that. H9 matches the OEM size.

Twglasgow

Audia889

Thanks for reply, could you please expand on recording part? Why do I need it and how do I go about it?

I know how to change car battery based on what I found on google but didnt knew I had to also recode

Twglasgow