I had to replace it to open the vehicle. I texted them when I had it towed to the service facility that I had replaced it to open the vehicle and install the tow hook. I informed them that the original battery was in the frunk. I asked them to fix all the issues with the car and informed them that I could return the Cdn Tire battery to Cdn Tire. When I got the notification that the car was fixed, I didn't see anything about the battery on the invoice, hence why I asked if the Cdn Tire battery was OK to which I got the reply, "it seems to be working at this time". I don't deny that a lot of the issue is miscommunication, but that is why I find it so frustrating that all the communication takes place via text.
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Model 3 completely dead this morning. What an experience. [dead 12v]
- Thread starter ggulik
- Start date
PianoAl
Active Member
Agreed. Very klunky and error prone.
Note that I asked Tesla to replace my 12V preemtively. Although I'd had no warning messages, they did it for free (I'm still under warranty), suggesting they found something wrong with it.
That would be my guess too .. since even something drawing power overnight would not drain the battery (since the charger was plugged in). I would leave the after-market stuff out for the time being and see if the problem crops up again so (a) you can start to figure out if it is the after-market display and (b) Tesla can't blame it the next time around.
If you monitor the voltage at the 12V battery posts, you get all the information you need regarding its charging/use status over time. I have a Bluetooth battery monitor device connected to the 12V battery posts which gives me around two months of voltage history. BTW, this device draws 1 ma. I review the 12V data on a regular basis to verify how long the car sleeps and how fast the voltage drops during sleep. I also can see when the car wakes up to top off the 12V battery, what the charge voltage is and how long it takes to perform the top off. Having this baseline knowledge helps me understand when something has changed in the charging regime over time for the 12V battery. Many things have changed over the past two years due to firmware changes. Monitoring this data helps identify a potential failure of 12V battery and troubleshoot the charging system components. If you have a problem with anything connected to either the HV bus or 12V bus, that could effect the 12V battery charging. If my 12V battery/car was dead, I would perform the follow steps. Get access to the 12V battery. Disconnect the negative terminal from the 12V battery and connect my 12V jump starter between the positive post and the disconnected 12V terminal. If the contactors close the car should wake up, otherwise you have more problems than a dead 12V battery. Remove the jumpstarter and monitor the voltage with a DC meter where it was connected. I believe you should see a voltage of 13.05V or more with the negative cable disconnected. If you do not, the DC-to-DC converter is not supplying power to the 12V bus for some reason. Next, while monitoring the voltage, reconnect the cable to the 12V post. The battery voltage state should be approx 14.4V charging or 13.05V maintaining the float voltage level. If the voltage is below 13V, the battery may not be charging due to a failing charging component of the car or the battery has a problem of some kind (shorted cell etc.).
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My warranty runs out at the end of this year, I'm hoping I can get Tesla to replace the 12volt battery on my 2018 Model 3 with the new lithium battery before then.
The lithium system in the new vehicles is not a direct replacement. Tesla would have to design some kind of retrofit battery as well as firmware changes.
I highly doubt that's going happen anytime soon.
PianoAl
Active Member
I decided to go with the regular 12V this time, and hopefully next time, a good lithium replacement that doesn't cause errors will be available.
I documented in another thread where my folks' Model 3 suddenly started draining 3-5 kwh per day for several weeks while parked, for those counting, that's a constant 125W power draw or constant 10-15A current draw:
Tesla says "Gray area for the warranty" and says I drained it [12V covered under warranty - resolved]
There are no 3rd-party accessories in the car, no use even of the in-car apps (no Sentry or anything), and it was hardly driven during those periods. I have a detailed timeline documented there with lots of timepoints from a remote logger - the only things that might've been coincident were a firmware update, and a 12V battery warning (one time). It started suddenly a few days after the firmware update when the vehicle was parked, and stopped suddenly weeks later without any new firmware update also while parked. In between, since the 12v battery was being cycled repeatedly the whole time, it was replaced a few days AFTER the drain stopped.
Given the absence of other activity other than a few short trips over those weeks, I could only guess one of two possible causes:
-a bad firmware update - not necessarily that the firmware itself was bad, but that an update without a hard reboot could've caused some app to misbehave and run constantly, and prevent the car from sleeping. This could've caused an eventual end to the 12V battery, though it was already 3.5 years old.
-a bad 12V battery - it was already old, a warning did pop up once before the start of the high drain, and a failing 12V battery could cause many of the electrical systems to misbehave, thus causing some of the software apps to misbehave, thus further causing the car to not sleep, etc.
I'm tending to believe it was the latter, that a bad 12V battery can cause all sorts of subsequent misbehavior, including high drain and deep cycling of itself. Which is to suggest that in the OP's scenario, it could've been the Hansshow or it could have been an end-of-life battery to begin with. Probably the Hansshow wasn't necessarily drawing the 3A itself, but over time its own power usage could've accelerated the cycling and decline of the 12V, causing the car itself to misbehave. Or just the old age of the 12V being the root cause.
Who really knows, but knock on wood, our own two Tesla's 12V original batteries are 4 and 5 years old respectively, I should get them both replaced soon...
Tesla says "Gray area for the warranty" and says I drained it [12V covered under warranty - resolved]
There are no 3rd-party accessories in the car, no use even of the in-car apps (no Sentry or anything), and it was hardly driven during those periods. I have a detailed timeline documented there with lots of timepoints from a remote logger - the only things that might've been coincident were a firmware update, and a 12V battery warning (one time). It started suddenly a few days after the firmware update when the vehicle was parked, and stopped suddenly weeks later without any new firmware update also while parked. In between, since the 12v battery was being cycled repeatedly the whole time, it was replaced a few days AFTER the drain stopped.
Given the absence of other activity other than a few short trips over those weeks, I could only guess one of two possible causes:
-a bad firmware update - not necessarily that the firmware itself was bad, but that an update without a hard reboot could've caused some app to misbehave and run constantly, and prevent the car from sleeping. This could've caused an eventual end to the 12V battery, though it was already 3.5 years old.
-a bad 12V battery - it was already old, a warning did pop up once before the start of the high drain, and a failing 12V battery could cause many of the electrical systems to misbehave, thus causing some of the software apps to misbehave, thus further causing the car to not sleep, etc.
I'm tending to believe it was the latter, that a bad 12V battery can cause all sorts of subsequent misbehavior, including high drain and deep cycling of itself. Which is to suggest that in the OP's scenario, it could've been the Hansshow or it could have been an end-of-life battery to begin with. Probably the Hansshow wasn't necessarily drawing the 3A itself, but over time its own power usage could've accelerated the cycling and decline of the 12V, causing the car itself to misbehave. Or just the old age of the 12V being the root cause.
Who really knows, but knock on wood, our own two Tesla's 12V original batteries are 4 and 5 years old respectively, I should get them both replaced soon...
And yet there are 12volt aftermarket lithium batteries for our Tesla and no one is having issues with those.
There are pages and pages of people with issues with Ohmmu lithium batteries and recent problems.
Mountain Pass makes one that use an aviation based lithium battery. It’s expensive and not in wide use. I’ve not heard of issues with the new Tesla firmware and these but it doesn’t mean that is the case.
Can support your assertion with any more information?
There is a way to get into your car when the 12v battery is dead.
Get a brand new 9v battery. Open up the tow hook panel on your front bumper. Look around inside for two wires. Touch the wires to the 9v battery and hold them until the frunk unlocks.
You can now attach a battery charger to your 12v battery. After the battery has been charged for a few minutes, you should be able to wake the car up. At this point, keep the car awake until you are able to replace the 12v battery. You can operate the car as usual, just make sure that you don't allow it to go to sleep.
Before you attach a battery charger to your 12v battery, inspect the 12v battery first. If you see any signs of bulging do not connect the battery to a charger.
Note that the 12v battery must be at or below ~9 volts in order for the 9v battery to open the frunk. If the 12v battery is above 9v but still not high enough to wake the car up, you can use a 12v DC power source on the wires behind the tow hook cover to open the frunk. Some guys have reported using a car battery charger with success, but I'd consider this a "do it at your own risk" situation.
A useful tidbit of information that kinda makes all this gel: Once the car is awake, the 12v system is no longer powered by the 12v battery, it is powered by the HV battery pack through the DC/DC convertor. So as long as your HV battery is charged, and the car is awake, the 12v system will be powered, even if the 12v battery itself is dead.
Thanks for the info. I had read a 9V battery would no longer work and to use a 12V battery. Did not know the 9V would still work if the car battery voltage was below 9V. Looks like it would be smart to not rely on a 9V battery to open the frunk.
I tried using a 9V and couldn't get it to open, though the 9V I used was new, the package was fairly old. At that point, I was pretty sure I needed a new battery anyways, so just bought the 12V from Cdn Tire. Because the HV system was faulting, it was only to get the car open, so I could install the tow hook. I had put it in my trunk, not my frunk, because when my car slid into a ditch in the winter, I couldn't get the frunk open (it had frozen shut), so they towed it out "carefully" by hooking onto an axle or something (can't remember what exactly, just remember no one liked doing it). Anyhow, car wouldn't go into gear because the HV system was faulting and lots of messages regarding the electrical system shutting down. By the time the car was towed the next day, the new battery was completely drained.
Now that the PTC heater has been replaced, I still have a 'low voltage battery needs replacement' message, but I don't think it really needs replacing. I checked on the weekend, and it's measuring about 13.5V, and seems fine. I would like to 'clear' the message, and see if it comes back. I tried disconnecting the negative on the battery for an hour, and that didn't clear it and also tried changing the tire config (another post indicated that would do a hard reset), but it didn't do anything (doubt it did a hard reset).
Now that the PTC heater has been replaced, I still have a 'low voltage battery needs replacement' message, but I don't think it really needs replacing. I checked on the weekend, and it's measuring about 13.5V, and seems fine. I would like to 'clear' the message, and see if it comes back. I tried disconnecting the negative on the battery for an hour, and that didn't clear it and also tried changing the tire config (another post indicated that would do a hard reset), but it didn't do anything (doubt it did a hard reset).
smatthew
Active Member
For that error you need to disconnect the 12V battery AND the HV harness under the rear passenger seat.
This just happened to me. No fix yet. I don't have any accessories plugged in. I was just on business for a month, left the car plugged in, and came back to this very issue. Even the engineers at Tesla don't know what's wrong.
My story below:
Tesla Model 3 Charging Issue
Hey y'all, hope this finds you well. I've got a situation and was hoping this community can provide insight. (The car is a 2018 Tesla Model 3 LR, still under full warranty) I went on a month long business trip last month and came back to find my car completely dead while it was plugged into...
teslamotorsclub.com
My Model 3 was delivered August 2018. My "12v needs replacing soon" warning just came up last night after I plug it in to charge. Our 2017 Model X's battery was replaced in 2020 just before 3 years. The Model X didn't even give any warning but the tech said the logs said it gave warning at 4am and died around 10am. I was told the life of a Tesla 12v is normally 3 to 4 years, so I guess I am due.
I scheduled Mobile 12v replacement this morning. Lets see how fast they could come out to do it.
I scheduled Mobile 12v replacement this morning. Lets see how fast they could come out to do it.
I am dealing with this issue now. I prefer to not call roadside assistance and have a person arrive that has never worked with Teslas. Instead, I’d rather have a mobile tech come out and replace the batter/ jump start the car, etc. When I go into the app, there is no real service option that deals with 12V battery and it also seems like the earliest appointment is not until the end of the month. How do I reach Tesla to have someone address this right away?
Unless things have changed, there should be a "12 volt battery service" (or worded similarly) in the list of services you can select from. At least, there was when I needed to have my 12v battery changed about a year ago. Mobile service came out and had it done in about an hour. I was actually surprised at how much of the front end/frunk they had to remove in order to swap out the battery; I'm glad I didn't decide to do it myself.
This worked! Finally had chance to do it on the weekend. Was a little worried, because I really don't know what I'm doing, but found a pdf with steps and pictures and it was very easy. Lifted the back seat off with two levers that slide towards the driver's side, lifted a sytrofoam enclosure off the rear passenger side, and then the harness you unclip and push the clip down and it sort of pushes it off (it was a little difficult to figure out what I was doing), but got it off. Left it for two minutes, with 12V negative unhooked and the message is gone. Has been gone for two days, so I think the battery is fine.
Thank you for your help!
I couldn't find it either so I selected "Something Else" and put in "12v battery needs replacement" and they scheduled Mobile Service 1 week out. The estimate is $125 by the way for changing it. My car will be sitting in the driveway for the week, even though it is not dead yet. I don't want to drive it and have it shut down somewhere out there.
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