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12 volt battery warning - rotten egg smell...can I drive it a week?

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Hi folks

My X has a service appointment in 5 days for another issue. The 12 volt battery warning light came on a few days ago, and now today there is a rotten egg smell. Does anybody have knowledge about this issue?

I have to say getting support from Tesla SUCKS. Nobody to ask. I mean really. I love the car so much but they need to step it up.
 
i had to wait 2 weeks before coming in for the next available scheduled service and it was intermittently farting in the garage, and it made it fine till i brought it in. but i have heard stories of people coming out to a dead car that they could not even get in, so your experience may vary. the most annoying thing was that i couldn't use summon or update the firmware until the battery was replaced. i would update your service appointment details to add that in there, otherwise they may not have available batteries for you. as of this past monday, SC in buena park is on back order and waiting for a lot of them, so best to notify them ahead of time before bringing it in, otherwise they won't have the part and you will be have to reschedule or wait for mobile tech to come.
 
Rotten egg smell is hydrogen sulfide (H2S) coming from your 12 volt battery. Beside being really stinky, it is very poisonous. You really want to get that battery changed out ASAP. If you are not driving it, disconnect the battery so it does not produce more H2S. Note that disconnecting the 12V will disable sentry, doors, lights, etc.

Hydrogen sulfide from battery charging is pretty rare. It only happens when the charger is way overcharging/too high voltage. As a temporary fix, you probably could stick any 12V battery in order to drive it to the service station. However that battery is likely to be damaged from overcharging, too.

The likelihood of actually getting poisoned is low since it is so smelly. However, it is very difficult to tell the difference between trace quantities (annoying, but not a too serious health issue) and really dangerous amounts. H2S is also very corrosive to metal. see Wet Hydrogen Sulfide (H2S) Cracking

So, beside potentially health issues and severe corrosion to the car, you might also be stranded somewhere.

What hazardous gases are associated with lead acid battery charging stations? | GfG Instrumentation | GfG Instrumentation
 
The smell is H2S from the battery. Lead acid batteries often give out a slight whiff of H2S (they contain lots of sulfate) but if it is strong something is definitely wrong and you should get it replaced ASAP. In the interim I'd leave the frunk unlatched. This is so that if the battery does go TU you can easily access the jump terminal and get enough DC into the car to open doors, put it in neutral etc.
 
i had to wait 2 weeks before coming in for the next available scheduled service and it was intermittently farting in the garage, and it made it fine till i brought it in. but i have heard stories of people coming out to a dead car that they could not even get in, so your experience may vary. the most annoying thing was that i couldn't use summon or update the firmware until the battery was replaced. i would update your service appointment details to add that in there, otherwise they may not have available batteries for you. as of this past monday, SC in buena park is on back order and waiting for a lot of them, so best to notify them ahead of time before bringing it in, otherwise they won't have the part and you will be have to reschedule or wait for mobile tech to come.


We have tried to update it but nobody responds to let us know they read it. It's really horrible.

Now I just looked at my app on my phone. It did show the upcoming appointment. Now it shows NOTHING about it, and doesn't have a button to MAKE an appointment.
 
If you want a battery right away these guys have them in stock and ship out fast. Also it’s a major upgrade over the lead acid batteries!

www.ohmmu.com

They are Lithium 12V specifically for Teslas.

Battery Management System prevents damage to battery in extreme situations and also balances the battery cells to maintain the pack for longer service life!

How safe is to put lithium 12v battery in Tesla? Is it in the right place to prevent damage from overheating? Tesla is using A/C to cool down main battery but not this one.
 
The pitch from Ohmmu suggests that there is a reasonably sophisticated BMS within the unit. So when the battery gets hot, stop or slow charging it. If the battery is too cold to accept charge at the desired rate turn on an internal heater. The 12V battery doesn't handle traction load or A/C compressor load so it probably isn't going to need cooling. The BMS is certainly sophisticated enough to balance 3 cells.

All speculation here, of course. The site implies these things but stops far short of telling what they are actually doing. As such I'd be interested in hearing from anyone who has had any actual experience with one of these. Handbooks list this chemistry as being good for 5 years but Ohmmu only warrants for 4. ??
 
We have tried to update it but nobody responds to let us know they read it. It's really horrible.

Now I just looked at my app on my phone. It did show the upcoming appointment. Now it shows NOTHING about it, and doesn't have a button to MAKE an appointment.
Through the app is the only way to make an appointment - if it works. It once took me three days to set one up. The trick was that I had to use a non existent address to get it to accept anything from me.

They removed the ability to make appointment from our on line accounts several months ago nor is there any indication of existing appointments in the online account.

I'd suggest reloading the app and seeing if your existing appointment pops up. If not, I can't think of anything to do except go to the SC or start all over with the app.

Yes, it really is horrible. It is this that I think will be the "Tesla Killer".
 
I just had this problem and scheduled an appointment. It put me out 2 weeks and my car died yesterday. The fire dept came out to the office because the smell was really strong and someone reported it (I don’t blame them).

I think Tesla should expedite battery issues to avoid cars dying on owners. It seems to be common and getting prompt service is impossible.

The Model X is a premium car. I wish I could say the same about the service.
 
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I just had this problem and scheduled an appointment. It put me out 2 weeks and my car died yesterday. The fire dept came out to the office because the smell was really strong and someone reported it (I don’t blame them).

I think Tesla should expedite battery issues to avoid cars dying on owners. It seems to be common and getting prompt service is impossible.

The Model X is a premium car. I wish I could say the same about the service.

Call roadside service since it is a safety item and see if that helps. When I had a flat tire and got the car towed in, service put me at the front of the list because it was a safety item
 
Same happened to me. Car lasted about 1 week and then odor started. I thought I had a sewer problem. Finally realized that the rotten egg smell seemed to follow me and found this thread. Called local Tesla service and got right in. Had mobile appt to replace the 12v on 12/4. They said that it’s safe to drive but some have reported that the car dies then has to be towed to service. The problem is that the 12v battery is being over charged.

Hi folks

My X has a service appointment in 5 days for another issue. The 12 volt battery warning light came on a few days ago, and now today there is a rotten egg smell. Does anybody have knowledge about this issue?

I have to say getting support from Tesla SUCKS. Nobody to ask. I mean really. I love the car so much but they need to step it up.