[Ender]

When I'm not going to drive the GT for a few weeks, I pop the hood.

Problem solved (for me).

Unfortunately, that was the easiest part to take care of. 5 mins to pop the hood.

 

[Snorlax]

It wont charge via the maintainer even using the force start setting. Based on the Taycan forums this is because the computer closes a relay when voltage is low (separate from BMS on the battery). The booster is enough to power the computer and kick everything on which should be able to then get the car going to charge the 12v. Oddly, it won’t.

do you have app access to the car during all
of this? i doubt it but i remember reading if you run the auxiliary HVAC from the app it will open the relay to recharge the 12v from the high voltage battery.

 

[Ender]

do you have app access to the car during all
of this? i doubt it but i remember reading if you run the auxiliary HVAC from the app it will open the relay to recharge the 12v from the high voltage battery.

Oh neat! I did read something similar in the Taycan forum. I dont though, the car is completely off. Seems like the Taycan got an update where the car periodically wakes up to charge the 12v a certain amount of time or until the high voltage battery is discharged to a certain SoC, whichever comes first. I hope we get an update like that as well.

 

[Snorlax]

i believe this is what the 93P9 update was intended ro address.

 

[RoyD]

My Noco Genius 10 documentation reckons that my sports bike should be fully charged in 1.5 hours. It never is, I top up bike or (other) cars overnight, whenever I charge them. I haven't yet needed to charge the GT 12v battery 🤞, but I'd assume that overnight would be a sensible period.

 

[Ender]

My Noco Genius 10 documentation reckons that my sports bike should be fully charged in 1.5 hours. It never is, I top up bike or (other) cars overnight, whenever I charge them. I haven't yet needed to charge the GT 12v battery 🤞, but I'd assume that overnight would be a sensible period.

I think it would be normally! It’s a tiny battery. The car is at the dealer now. The service advisor said “this is rarely ever just an issue with the battery”. Hopefully I’ll find out tomorrow.

 

[JNealCox]

I think it would be normally! It’s a tiny battery. The car is at the dealer now. The service advisor said “this is rarely ever just an issue with the battery”. Hopefully I’ll find out tomorrow.

The service advisor is probably right. This should not happen. The car has a phantom drain somewhere, or is not topping off properly.

 

[Ender]

The service advisor is probably right. This should not happen. The car has a phantom drain somewhere, or is not topping off properly.

The first thing I’m guessing they will do is try and blame my dash cam. It’s hardwired to an external battery in the lower trunk compartment though. It does charge off the 12v accessory port back there that turns off when the car is off. I highly doubt it would be related though and I will fight that one. I confirmed that battery discharges when the car is off so it would have to be a big problem with that port.

 

[sambill]

When I'm not going to drive the GT for a few weeks, I pop the hood.

Problem solved (for me).

I noticed when the hood is popped the LED light in the frunk storage is on btw...

 

[Ender]

I noticed when the hood is popped the LED light in the frunk storage is on btw...

I believe you can just put a towel over the latch and then put the hood down and the light turns off.

 

[Jetmart]

I noticed when the hood is popped the LED light in the frunk storage is on btw...

The light will go off in 10 or 15 minutes with the frunk hood open.

 

[Ender]

An update for anyone following along: the car has been in the shop for 11 days now. They ended up having to call in Audi tech support and were given a battery of tests to run through. It was determined that the issue is the front and rear drive control modules need to be replaced. They managed to get the last ones in the country, which will take anywhere from 3-10 days to arrive and a few days to replace.

I'm unclear how this is related to the 12v battery (unless the modeules were running it down) or how confident they are that this will remedy the issue. In any case, I will be asking AFS for a lease credit and will strongly consider pursuing a lemon if this doesn't fix it.

 

[gk1]

So they still haven't just tried replacing the 12v battery?
I know it is super expensive ($1200), but what happened to "if it looks like a duck..."
These things can (and do) fail. Sometimes for no apparent reason. Maybe you just god a bad one.

 

[Ender]

I have just been texting the service advisor and haven’t asked a ton of questions yet. They may have replaced the battery already, but I think the unexpected thing was that the car would not go into Drive when the computer was powered. To get it from the parking lot to the shop they had to bring a WiFi hot spot and connect the car to the internet 🤷‍♂️

So my guess right now is that the battery issue was just secondary to the module issue. I’ll ask a lot more questions when I pick up the car or if it doesn’t solve the issue.

 

[gk1]

Also I thought there was a method to connect emergency power to open the frunk? (Admittedly I never checked myself.)
or if that is only for Euro then TSB(2064296/1)

https://www.e-tronforum.com/threads/fyi-theres-a-manual-solution-for-getting-the-frunk-open-if-the-12v-battery-is-depleted.4237/

 

[Ender]

Only the euro version and the Taycan unfortunately.

 

[gk1]

I have just been texting the service advisor and haven’t asked a ton of questions yet. They may have replaced the battery already, but I think the unexpected thing was that the car would not go into Drive when the computer was powered. To get it from the parking lot to the shop they had to bring a WiFi hot spot and connect the car to the internet 🤷‍♂️

So my guess right now is that the battery issue was just secondary to the module issue. I’ll ask a lot more questions when I pick up the car or if it doesn’t solve the issue.

OK it does seem like the 12v itself is quite complex too.
So nearly anything could have "wacked it out".

If the 12 volt battery is drained in the case of a breakdown, please note:
~ Supply the battery with power from external sources (jump starting/starting assistance)
= page 283.
— Power should be supplied to the 12 volt battery from an external source for at least 5 minutes.
The 12 volt battery will be automatically connected to the vehicle electrical system again.
~ Then establish drive ready mode.
~ After establishing drive ready mode, the 12 volt battery must be charged for at least 10 minutes using a charger. Then the electrical system will reactivate automatically.
If there is a repeated need for the 12 volt battery to have power supplied from external sources or to be charged while operating under normal operating conditions, this may indicate that the 12 volt battery is damaged.

Also mentions not more than 14.8V 90A charging as that can trip internal relays in the battery.

 

[gk1]

Only the euro version and the Taycan unfortunately.

Then TSB(2064296/1) should work, but you have to get the car on a lift...Ha

 

[Ender]

Then TSB(2064296/1) should work, but you have to get the car on a lift...Ha

lol, yes I much prefer the 10mm wrench or pigtail method.

 

[gk1]

Only the euro version and the Taycan unfortunately.

I went and had my own look and it does exist!
At least on my '23 anyway.