Bad luck with Tesla 12V batteries this week.

[Az_Rael]

A few weeks ago my husband's 12V failed on his S during a software update leaving the car stranded in our garage. What are the odds, right?

Well, tonight I go to drive my 3, and she is dead as a doornail. Get the 12V jumped, and guess what? Failed during a software update. I then recalled never getting the "update complete message when I kicked off the update earlier" Man that 12V battery STINKS when it fails in your garage.

Let it charge for long enough to get it running and out of the garage, thankfully, as the sulfur was smelling up the house too.

Tow truck comes tomorrow.

No prior warnings the 12Vs were dying. I should buy a lotto ticket or something.



Anyway: I am now an expert at jumping both the Model S and the Model 3. So small wins I suppose.

 

[Gasaraki]

At least it failed at home.

You would think the Tesla computer an check the condition of the 12V battery like how UPSes check the batteries once a day.

 

[Az_Rael]

You would think the Tesla computer an check the condition of the 12V battery like how UPSes check the batteries once a day.

I know, right? And especially before applying a software update.

 

[camalaio]

Y'know, there's been a lot of 12V incidents coinciding with updates in the last couple weeks. I'm starting to think this pattern isn't just a coincidence.

That battery must've been really really dead to start stinking. Like a load was left on it unintentionally by some system. Really weird.

 

[Az_Rael]

Y'know, there's been a lot of 12V incidents coinciding with updates in the last couple weeks. I'm starting to think this pattern isn't just a coincidence.

That battery must've been really really dead to start stinking. Like a load was left on it unintentionally by some system. Really weird.

That is my husbands theory: something has been changed in the software update process that can kill a 12V.

 

[SSedan]

Heat is very hard on lead acid batteries, though people think it is cold, cold is just when the summer heat damage always shows in ICE with weak cranking.

 

[camalaio]

Heat is very hard on lead acid batteries, though people think it is cold, cold is just when the summer heat damage always shows in ICE with weak cranking.

These batteries are in much nicer conditions than an ICE. No hot engine nearby (if heat is indeed a factor), and relatively low peak power draw (no engine cranking).

And speaking from experience, a brand-new cold lead-acid battery doesn't really perform well in Winter either.

 

[SSedan]

Cold slows the chemical reaction. Heat does damage. It is a good point that the Tesla 12volt doesn't have engine heat but my point was.more that the weather has gotten warm.and that might be why a few 12volts failed close together.
Then again Tesla could have a big n the software update that hangs up and drains the 12volt.

Far as the conditions the 12volt sees it is different than an ICE bit the constant deep cycles are hard in a different way.

 

[camalaio]

Cold slows the chemical reaction. Heat does damage. It is a good point that the Tesla 12volt doesn't have engine heat but my point was.more that the weather has gotten warm.and that might be why a few 12volts failed close together.
Then again Tesla could have a big n the software update that hangs up and drains the 12volt.

Far as the conditions the 12volt sees it is different than an ICE bit the constant deep cycles are hard in a different way.

The 12V battery on a Model 3 isn't deep cycled though with usual operation. Nor do they let it die under normal operation. It's charged pretty constantly while driving, and tops up if it gets too low otherwise.

I get you're just explaining a possible cause (thanks for the info btw!). If that could explain it though, we'd see more routine ICE 12V battery death IMO. And the Model 3 still shouldn't be letting the 12V die.

 

[Matsayz]

Lots of dead 12V batteries are coming up. My local group in Vegas has had at least 5 in the past 2wks.

Do we have a sticky thread for how to jump or replace the battery? That might be something nice and easy to post for future threads of “dead 12V”

 

[camalaio]

Lots of dead 12V batteries are coming up. My local group in Vegas has had at least 5 in the past 2wks.

Do we have a sticky thread for how to jump or replace the battery? That might be something nice and easy to post for future threads of “dead 12V”

It's in the manual FWIW. The trickiest bit is bypassing the frunk latch if the 12V battery is truly dead, which has a workaround in the manual as well. On Android you can try to pop the frunk via the persistent notification (this goes through Bluetooth and may work even if the app does not). Not sure if iOS has an equivalent feature.

1. Open the hood (see Opening Hood with No Power on page 20).
2. Remove the maintenance panel by pulling it upwards to release the trim clips that hold it in place.
3. Remove the cabin intake trim panel by pulling it upwards to release the trim clips that hold it in place.
4. Connect the 12V power supply's red positive (+) cable to the red positive (+) terminal on the 12V battery. CAUTION: To avoid damaging Model 3, do not allow the positive cable to contact other metal components, such as the battery tie-down bracket.
5. Connect the 12V power supply's black negative (-) cable to the black negative (-) terminal on the 12V battery.
6. Turn on the external power supply (refer to the manufacturer’s instructions). Touch the touchscreen to wake it up. NOTE: It may take several minutes to receive enough power to wake up the touchscreen.
7. When external 12V power is no longer required, disconnect both cables from the terminals on the 12V battery, beginning with the black negative (-) cable.
8. Replace the cabin intake trim panel by placing it back in its original location and pressing down until it is secure.
9. Replace the maintenance panel by placing it back in its original location and pressing down until it is secure.
10. Close the hood.

Note that there are pictures in the manual if you have no idea (like me) what a "cabin intake trim panel" is.

 

[Matsayz]

It's in the manual FWIW. The trickiest bit is bypassing the frunk latch if the 12V battery is truly dead, which has a workaround in the manual as well. On Android you can try to pop the frunk via the persistent notification (this goes through Bluetooth and may work even if the app does not). Not sure if iOS has an equivalent feature.

1. Open the hood (see Opening Hood with No Power on page 20).
2. Remove the maintenance panel by pulling it upwards to release the trim clips that hold it in place.
3. Remove the cabin intake trim panel by pulling it upwards to release the trim clips that hold it in place.
4. Connect the 12V power supply's red positive (+) cable to the red positive (+) terminal on the 12V battery. CAUTION: To avoid damaging Model 3, do not allow the positive cable to contact other metal components, such as the battery tie-down bracket.
5. Connect the 12V power supply's black negative (-) cable to the black negative (-) terminal on the 12V battery.
6. Turn on the external power supply (refer to the manufacturer’s instructions). Touch the touchscreen to wake it up. NOTE: It may take several minutes to receive enough power to wake up the touchscreen.
7. When external 12V power is no longer required, disconnect both cables from the terminals on the 12V battery, beginning with the black negative (-) cable.
8. Replace the cabin intake trim panel by placing it back in its original location and pressing down until it is secure.
9. Replace the maintenance panel by placing it back in its original location and pressing down until it is secure.
10. Close the hood.

Note that there are pictures in the manual if you have no idea (like me) what a "cabin intake trim panel" is.

I think that should be a sticky along with the link to the manual. https://www.tesla.com/sites/default/files/model_3_owners_manual_north_america_en.pdf

 

[camalaio]

I think that should be a sticky along with the link to the manual. https://www.tesla.com/sites/default/files/model_3_owners_manual_north_america_en.pdf

Tadaaaa: 12V Battery Issues? Car not responsive? Try this!

We'll see if it gets stickied, hopefully someone sees it if they need it.