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Dead 12V Battery Issue - Frunk doesn’t open

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I was away for 6 weeks and when I came back I found my 2021 Tesla is dead, after researching I realized that my 12V battery is dead.

I tried opening the doors and frunk using the app and the card. Nothing worked.

I did exactly what it said in the manual by connecting 9V and 12V batteries to the cables in the tow hook port.

Didn't open and didn't hear the latch moving at all.

Now I'm stuck, what can I do to access the battery?

Given that I charged the battery before I leave till 85%.
 
What kind of 9V and 12V batteries did you connect? Your garden variety 9V may not have enough amperage to unlatch the frunk. A low amperage battery charger or even a tender should have enough oomph to do the job.

You notice that the instructions suggested something like a jump pack.

I tried a new car battery for the V12 and the 9V I used a normal Energizer battery.

Suggestions?
 
I tried a new car battery for the V12 and the 9V I used a normal Energizer battery.

Suggestions?
Check polarity to make sure you didn't mix up positive and negative. Also aid the frunk unlock by lifting up a bit with your finger. It's possible your 12V battery in your car still has some charge, enough to disable the frunk popping, but not enough to allow you to unlock. It's this awkward situation that is most worrisome.

When you say you tried the app, are you using the bluetooth based phone key? This is different from the LTE based unlock.
 
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Got a ride to the service center in the morning to buy a replacement 12v battery. Service person checked with the mobile ranger and made a appointment the same afternoon. Mobile ranger use the new 12v battety and it pop the frunk and swapped the battery.
 
Does this also happen to MY and old '17 X?
Not sure about the Y, but I would assume the emergency opening procedure is the same as a 3. On the X there are two hidden straps in the lower front grill are that must be pulled to open the frunk. Once you have the frunk open it is pretty easy to change out a dead battery. All of this is covered in the manual.

The model X is known for having short 12V battery life. At 2 years some people replace them proactively. The 2022 and on Model Xs, no longer use a standard 12V battery and instead use a smaller (hand size) and lighter 16V Li-Ion battery. I assume at some point all of the cars will use a similar battery.
 
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Not sure about the Y, but I would assume the emergency opening procedure is the same as a 3. On the X there are two hidden straps in the lower front grill are that must be pulled to open the frunk. Once you have the frunk open it is pretty easy to change out a dead battery. All of this is covered in the manual.

The model X is known for having short 12V battery life. At 2 years some people replace them proactively. The 2022 and on Model Xs, no longer use a standard 12V battery and instead use a smaller (hand size) and lighter 16V Li-Ion battery. I assume at some point all of the cars will use a similar battery.

TSLA should put a voltmeter and warning system on the 12V.
 
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It does. And it gives you a warning in the app. *That is if it's not an sudden/instant failure when the car is "off." At that point, you're SOL.

GTK I had mine proactively replaced by SC b/c it was bulging/odor in 2020. But ranger said now bulging is considered normal??. AZ heat is harsh on these so I'm hoping TSLA will replace again proactively b/f next summer, while under warranty (expires 6/23)


15-Jun-2020
Concern: Tech noted during inspection, foul odor?? coming from frunk area.
Replaced 12V Battery. Verified Proper Operation.
Correction: Battery - 12V (Remove & Replace)
Parts Replaced or Added
Part Quantity
ASY,12V BATT AND VENT PLUG,M3(1129182-00-B) 1.0

Pay Type: Basic Vehicle Limited Warranty
 
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I was away for 6 weeks and when I came back I found my 2021 Tesla is dead, after researching I realized that my 12V battery is dead.

I tried opening the doors and frunk using the app and the card. Nothing worked.

I did exactly what it said in the manual by connecting 9V and 12V batteries to the cables in the tow hook port.

Didn't open and didn't hear the latch moving at all.

Now I'm stuck, what can I do to access the battery?

Given that I charged the battery before I leave till 85%.

Got a ride to the service center in the morning to buy a replacement 12v battery. Service person checked with the mobile ranger and made a appointment the same afternoon. Mobile ranger use the new 12v battety and it pop the frunk and swapped the battery.

Ok, Im confused here. The OP in this thread is @Ghassan A. . Then, in post #5, it appears @Sinh2bo is responding in a continuation of what @Ghassan A. situation was, making it appear these two accounts are the same person.

Before I start trying to see if these two accounts are one person (and ban one or both), perhaps both of you can let me know whats going on here?
 
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Check polarity to make sure you didn't mix up positive and negative. Also aid the frunk unlock by lifting up a bit with your finger. It's possible your 12V battery in your car still has some charge, enough to disable the frunk popping, but not enough to allow you to unlock. It's this awkward situation that is most worrisome.

When you say you tried the app, are you using the bluetooth based phone key? This is different from the LTE based unlock.
I tried again and made sure the polarity is correct to no success.

As for the app, I tried the LTE based app. I couldn’t connect using Bluetooth
 
I tried again and made sure the polarity is correct to no success.

As for the app, I tried the LTE based app. I couldn’t connect using Bluetooth
LTE unlock requires the car being fully awake, plus it is also dependent on reception/local cell service. The bluetooth might still work if it's not fully awake. Did you try pulling the handle to see if screen shows anything? Is your HV battery dead also? What state of charge did you leave it at?

As another mentioned, when you apply the power to the tow hook leads do you hear any sounds from the latch? If you do, you can aid it a bit by lifting with your fingers.

Do you have a multimeter to check that the batteries that you are using have charge (just to eliminate all possibilities)?
 
Ok, Im confused here. The OP in this thread is @Ghassan A. . Then, in post #5, it appears @Sinh2bo is responding in a continuation of what @Ghassan A. situation was, making it appear these two accounts are the same person.

Before I start trying to see if these two accounts are one person (and ban one or both), perhaps both of you can let me know whats going on here?
I have only one account, which is Ghassan. I don’t know who @Sinh2bo is.
 
LTE unlock requires the car being fully awake, plus it is also dependent on reception/local cell service. The bluetooth might still work if it's not fully awake. Did you try pulling the handle to see if screen shows anything? Is your HV battery dead also? What state of charge did you leave it at?

As another mentioned, when you apply the power to the tow hook leads do you hear any sounds from the latch? If you do, you can aid it a bit by lifting with your fingers.

Do you have a multimeter to check that the batteries that you are using have charge (just to eliminate all possibilities)?
I tried opening the handle, the screen stayed off.

When I left the car it was at 85% charge.

As for the sounds, I didn’t hear any sound with the battery, so I tried a new 12V battery, same issue. Then I brought another car while it’s on and used the cables and same thing.

I brought a voltmeter and set it to DC voltage, it only showed -0.06V. So I tried the 9V battery again thinking the cables are switched. To no success.
 
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