812 Manittino failure

Yes .. definitely sounds like a weak/ low battery situation..

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First, yes, an ailing battery will cause all kinds of problems. They ended up replacing my factory original battery with a new battery (AGM, FWIW), and that has made the car much better.

In the meantime, once you've driven the car a bit (with Auto-Stop/Start TURNED OFF) to charge up the battery, you can stop the car and perform the key fob reset procedure to try to clear the errors. Basically, you stop the car and turn off the engine. Then, without opening any doors (may or may not matter, but that's what I did), you press the lock button on the fob, then press the unlock button in a second or two, then keep doing that for 4 or 5 cycles. You can stop when the car doesn't respond to a button press. Wait about 10-15 seconds, and you can start the car. At that point, the errors caused by the low battery should be cleared, at least until the battery gets low again and they come back.

 

New battery time

 

1 1/2 weeks off charge? You're dicing with danger.
Another 1/2 a week and you'd have been lucky to even start the car, especially given the age of the battery. You'll also be shortening the battery life by allowing it to discharge so low.

As Stew says, it's new battery time. And keep it on charge.

 

The V12s cook their batteries faster than the V8s because the V12 batteries are located in the engine compartment. Cooking the battery dramatically shortens its life. I view batteries in the V12s as consumables and change mine every two years.

 

Yes - even though my FF is not HELE, I run an AGM battery. I tried to fit a non-AGM battery and the CCA of a new non-AGM was similar to the two year old AGM which I'd had in the car previously so I returned the non-AGM for another AGM battery.

 

Yeah - replace it with AGM. Others have had success with LiPo batteries but the cost difference far outweighs the lifetime difference. The only advantage LiPo has is the ability to provide a reserve 'boost' function to get you started if the main battery has run flat. Given that I don't get into these situations, it's not a feature I have a use for but I can see how it could come in handy if you have to leave your car off tender for weeks at a time.

 

H7

 

812 should be AGM as stock. F12 is AGM. Stock OEM brand is crappy but mine did fine for 6 years. When they crank slow - out they go!

 

https://braillebattery.com/products/b7548-1

anybody have luck with one of these? was thinking of replacing the battery in my 812