1. Introduction
There are 2 types low voltage batteries which are equipped in Tesla cars.
- Lead-Acid (12V)
- Lithium-Ion (16V)
How to check which type of battery is equipped in your Tesla car?
Software > Vehicle Additional Information > Low Voltage Battery Type
You should replace your car car low voltage battery with the same type of battery. If you need help to choose correct battery for your car. Please free to contact us.
We also Repair low voltage battery for all Tesla cars. Please free to contact us
How to close MOSFET
In some situation and one of most common situation after accident, System will open MOSEFET to protect low voltage battery. Please read below more details about in which situation, system will open MOSFET.
There are 3 ways to close it. Please feel to contact us to get know how it can be fixed. We will be happy to help you.
2. Repair existing 16V LV Battery instead replacement
In most of cases, it could be possible to recover 16V Low Voltage Battery. Please contact us to get to know how to recover LV Battery. Some of workshop partners can do for you in your region.
3.1 When could be possible to recover?
Please read more details below. Else, please feel to contact us with your alert screenshot.
3.1 Cost to fix
Our remote diagnosis and support fee.
3. Accident Repair Tesla 16V Low Voltage Battery?
In most of cases, low voltage battery will drain after accident and MOSEFT will get open. In most cases, it is possible to recover battery.
Please contact us, we will be happy to help you to let you know whether you need to replace or its possible to recover battery.
- How long was car standing after accident?
- Was it drained below 9V?
Car might not recognize low voltage battery, if car was standing long time. You may need to replace LV Battery.
4. Remote Diagnosis and Support to close MOSFET
Please send us your "Service Alert" Screenshot via Contact or Whats App +49 (0) 15226242038. For quick support and interactive support, please contact us via What's App. We will be happy to provide you support to clear alerts with affordable prices without going to service center which could save your money and time. We can help you to explain the possible cause, how to diagnose, how to fix/reset/repair etc.
Reasons not to close MOSFET
Some of most common possible causes could be followings:
Low Voltage Battery not supported by High Voltage Battery
Service Mode - High Voltage
Check if you see anything in Red under High Voltage. There are some sub-menu under Voltage. Everything should be in green. Its important that low voltage battery is supported by High Voltage.
Contactors
Contactors are open
Service Mode - High Voltage
PCS
VCFront
Load Shed
ECPA
Harness
One of reason could be that harness are damaged, not properly connected, routed after recent repair or accident repair work. Please make sure its not damaged, installed properly.
Learn New Battery After replacement
Touchscreen > Low Voltage > Power Distribution > Battery Icon > Learn New Battery and click Run to start the process.
If the battery is CATL_LI_ION. It need to reinstall the car software.
Software Reinstall/Update
If the battery is CATL_LI_ION. It need to reinstall the car software.
Steps to close MOSFET
Please make sure that VCFRONT, PCS, ECPA, DC-DC, HVP are green and contactors are closed.
Jump Start/LV Maintainer
How to close MOSFET, ECPA.
There are couple of ways. It could vary depend on conditions, alerts. There are different techniques to clear/reset/close. Please feel to contact us.
How to clear via Service Mode
If you would like to know how to close via Service Mode. Please feel to contact us.
If you have already tried to close. However, it did not work. Please feel to contact us. We could help you remotely to close it.
How to clear via Toolbox
Actions - LVBMS Reconnect LV Battery - Run
How to close with other techniques
Please feel to contact us. We will help you.
5. Appointment to replace Tesla Low Voltage Battery in best affordable Workshop
Alert Code
Some of most common possible alert code.
You might have received one of following alert.
VCFRONT_a182
- VCFRONT_a182_replace12VLVBattery
VCFRONT_a402
- VCFRONT_a402_LVBatteryCannotSupportVehicle
- The vehicle controller has detected a condition where the low voltage (LV) battery is unable to support vehicle electrical systems.
- 6425300, 3272200
VCFRONT_a477
- VCFRONT_a477_LVBatteryUnrecoverable
VCFRONT_a478
- VCFRONT_a478_LVBMS_MOSFET_Open
VCFRONT_a495
- VCFRONT_a495_LVBatteryRecoveryBlcoked
VCFRONT_a496
- VCFRONT_a496_LVBatteryExitDriveWarning
VCFRONT_a528
- VCFRONT_a528_LVBatteryCommsDiscnctd
Please send us your "Service Alert" Screenshot via Contact or Whats App +49 (0) 15226242038. We will be happy to provide you support to fix/reset alert with affordable prices without going to service center which could save your money and time. We can help you to explain the possible cause, how to diagnose, how to fix/reset/repair etc.
Buy 16V Lithium Ion Low Voltage Battery
Battery Part Number
If you would like buy 16V Lithium Ion Low Voltage Battery. Please have a look in our catalog or contact us.
| Model | Part Number | Part Name |
| 3 | 1598486-00-F |
6 How to remove and replace Tesla Low Voltage 16V Battery?
How to Disconnect & Connect
Guide to disconnect & connect. Link
How to Replace 16V Low Voltage Battery
If your car has software FW 2023.44 or later version. Touchscreen > Low Voltage > Power Distribution > Battery Icon > Learn New Battery and click Run to start the process.
If the battery is CATL_LI_ION. It need to reinstall the car software.
Guide for Tesla Lead Acid 12V Low Voltage Battery
In case, if you car is equipped with 12V Battery. Please have a look in another guide Link
Frequently Asked Questions
MOSFET
What is MOSFET?
Tesla lithium-ion 16V Battery consist with MOSFET Transistor on circuit board. MOSFET is internal switch/transistor, which opens the circuit in some circumstance to protect the battery.
When MOSFET Transistor open?
It opens to protect battery from damage in some of following conditions:
- Low State Of Charge (SOC)
- Cell under/over voltage
- Pack under/over voltage
- Pack charge/discharge over current
- When State Of Charge (SOC) is less than 10%
- It could happen when you drive until HV Battery charge get zero miles/km
- When HV Battery charge is zero (when you are outside town and car is not connected to charger)
- Car is idle after accident for couple of weeks. Please let us know how many days/weeks car was idle after accident. We will let know if its possible to close MOSEFT.
- If any cell from four cells voltage is less than 3.46V or more than 4.3 V
- We could remotely check it. It is also possible, you could check yourself. Please contact us. We will be happy to help you. Service Mode - Low Voltage - Click on Low Voltage Battery Symbol. You will able to see cell voltage. Please send us photo. We will be happy to help you.
- If Battery pack voltage is less than 13.8V or more than 17.2V
- We could remotely check it. It is also possible, you could check yourself. Please contact us. We will be happy to help you. Service Mode - Low Voltage - Power Distribution. Please send us Photo.
- If discharge current is greater than 400A.
- When someone has used to jump start another car
Please feel to contact us to close it. We will perform remote diagnosis and support to close it.
What could be the Voltage when MOSFET is open?
It could be zero. It might not read anything. It might show some readings, however it might not capable.
How much should be the voltage?
It should be around 15.6V (15.5V) during normal operation
What is operating Voltage Range?
15.5 - 15.8
What is State of Charge Target?
Runs at targeted state of charge between 75-85%
What is Ah Capacity
6.9 Ah
Tool needed to close MOSFET?
You need power supplier, which can produce/handle between 13.5 -15.5 Volts. It must handle 40 amps, 50 amps would be preferred.
Please do not use 12V power supply. Its not enough for 16V Battery.
Car does not recognize the battery
Car might not recognize if battery was lower than 9V. So, you might need to replace battery. Please contact us for more details.
Battery Recovery
When MOSFET will close
It wil close when
- HV is working
- PCS is supporting
Cell Voltage
CATL_LI_ION > 2.1v
TESLA_16V_LI_ION > 1.8V
TESLA_48V_LI_ION (Cybertruck) > > 1.8V
Some more information about Tesla 16V LV Battery
16V Battery has
- Battery Management System (Does cell balancing, 4 Cells)
- Self-Protection Mode (It shuts off input and output to protect from over and under-charge in certain circumstances)
- LIN Data Communication (communication line between Low Voltage Battery and VCFRONT)
16V Battery has 5 Terminals (Positive, Negative, Electronic Connector Position Assurance (ECPA) LIN Data)
Battery has circuit board and connector.
Push-Fit Electrical Connector?
Is it possible to repair?
Yes, its possible to repair in some cases. You might not need to replace replace.
Can I repair/replace myself?
It could be possible. If you have needed Tools, Know-How, Time etc. Please feel to contact us. We will be happy to provide you remote support.
Note: Please do not work with high voltage components. If you do not need needed/proper Tools, Know-How etc. It could be dangerous.
Can I do at Local Workshop, Independent Tesla Workshop?
Yes, you can. However, please make sure that workshop knows how to work to Tesla Cars. If local workshop need any support. Please feel to contact us. We will be happy to provide online shop. You can also find workshop in our Workshop Locator.
Mobile repair service?
We could also provide mobile services. Please feel to contact us where are you located and what kind of repair are you looking for.
Car not under warranty, salvage, accident, flood, modified cars?
It is highly recommended to perform repair with independent workshop to save money.
Alert still appearing after repair?
There could be many reasons. Some of reasons could be please make sure that repair was done in correct way, did you restart system after performing repair? did you Reinstall Firmware? Did you use used spare parts? Still appearing alert: Please free to Contact Us. We will be happy to provide you online support. Phone/Whats App +49(0)15226242038
Where is low voltage battery located inside the car?
Under the front frunk.
How to check whether current battery is bad?
How to check which type of battery is equipped in your Tesla car?
Software > Vehicle Additional Information > Low Voltage Battery Type
How to check Lead-Acid (12V) in Tesla cars?
Software > Vehicle Additional Information > Low Voltage Battery Type > Lead-Acid
How to check Lithium-Ion (16V) in Tesla cars?
Software > Vehicle Additional Information > Low Voltage Battery Type > Lithium-Ion
Which Tesla cars are equipped with Low Voltage Lead-Acid Battery?
Car produced in
- Gigafactory Shanghai before approximately October 2021
- Fremont Factory before approximately December 2021
Which Tesla cars are equipped with Low Voltage Lithium-Ion Battery?
- Car produced above dates are quipped with a Lithium-Ion Low Voltage Battery.
How to Jump Start?
Please read more details in Owner's Manual or DIY.
