Tesla High-Voltage Battery repair guide (Remote diagnosis and support to clear alerts)

1. Introduction

In this guide, you will get all information about How to diagnose, How to repair, How to remove and replace, How much it could cost part and labor, How to get remote support, Find and compare best affordable workshop in your region and book an online appointment for repair, Information about spare part number and name, How and where to buy new, remanufactured and used spare parts with best price etc.

For quick support, Please write us via Whats App +49(0)15226242038. We will be happy to help you. 

In most of cases high voltage battery could be repaired instead battery replacement with new battery, which could save 10-20 thousands of euro/dollars, which is also sustainable.  

1.1 What could cause the high voltage battery to fail?

There are many reasons. Some of most common reason may be followings:

• One of typical cause is moisture accumulation, water ingress in Battery.
• Isolation Alert
• Physical damage
• Cell Imbalance

There are some Tesla Battery Independent specialist shops which offer battery REPAIR with affordable prices. OEM and most of workshop just replace High Voltage Battery pack without repair, which is not sustainable and cost couple of thousands euro/dollars to customers. Please feel to contact us, we provide remote support to repair for workshop person, car owner DIY etc. Please contact us for more details.

2. How to Diagnose

It is possible to do diagnose via Remote Diagnosis, Service Mode. 

2.1 Remote Diagnosis

Please read more details about Remote Diagnosis in another guide (How to do, Cost etc.) Link If you need support. Please Contact Us Phone/Whats App +49(0)15226242038

2.2 Service Mode

It could be possible to find out the exact cause of the alert with the help of services alerts in Service Mode.

How to check service alerts in Service Mode

• On the touchscreen, click Controls (vehicle icon) > Software
• Touch and hold the large word "MODEL" for 4 seconds and then release.
• Enter "service" as access code.
• After clicking on Service Alerts. You can read service alerts. If there is anything wrong with car. It will show in active alerts.

Please read more details in another guide (How to do enable Service Mode) Link

In case, If you need support for diagnosis. Please Connect Us.

Please send us "Service Alert" Screenshot via Contact or Whats App +49 (0) 15226242038. We will be happy to help you to explain alert and how could be fixed, cost, support for fixing if possible online support or to organize an appointment with independent best affordable workshop.

Depend on alert/fault code, car might need to be repaired/serviced.

How to diagnose fault inside Battery pack?

Our remote diagnosis solution can help you to find the fault in battery pack, faulty brick, module etc, which could save your time. 

We had recently a customer who open the battery pack. He found everything perfect. He cleared the alert. When you put battery pack back he got again same alert. He contacted us. We performed diagnosis and informed him faulty module and brick number. 

If you need support. Please contact us via Whats App +49(0)15226242038

Customer Feedback screenshot

3. Most common Failures

Some of most common failures

Imbalance

When cell voltage will be more or less than minimum and maximum threshold. It will create imbalance issue. 

Cell Voltage threshold (Minimum and Maximum)

How to fix

There are some methods to make cell balancing. Please contact us for more details.

4. How to remove HV Battery

Disablement High Voltage 

• Follow Vehicle HV Disablement Procedure
• Follow safety procedure from OEM related to car/model
• Procedure could vary 

Take down the HV Battery

Remove Top Plastic Cover (Battery Insulation Blanket)

• Check if you see any sign of water below plastic cover. 

Remove bolt which holds top cover of battery pack

There are mica sheets on top of each battery Module 

There are coolant hoses inside battery pack

How to drain the battery 

It could be drain out the battery with Toolbox or other ways. Initiate battery drain process.

5. HV Battery Pack Architecture

Pack

Tesla's High Voltage Battery pack is made up with 16 Modules in series. 1 Module gives approximately 24 Volts (16 Module * 24 Volts = 400 Volts total).

Where are module located/numbering?

• Module 1 is located on the left side at the back. 
  
• Module 7 is located on the left side at the front. 
• Module 8 and 9 are located very front (8 on bottom and 9 on top)

16 Module Pack Architecture

	9
	8
7		10
6		11
5		12
4		13
3		14
2		15
1		16

14 Module Pack Architecture

7	8
6	9
5	10
4	10
3	12
2	13
1	14

Module 

A module is made up with bricks.

There are 6 bricks in 1 module. Module has approximately 24V (6 Bricks x 4 Volts). Module is made up with 444 individual cells. 

Bricks

Brick is a group of cells electrically connected in parallel. 

85kWh Battery pack

Brick is made up with 74 cells connected to the same plate in parallel. 

When you diagnose via some Tools/Application. They call it cells however, its brick. 

Cell

Cell is smallest component in Battery Pack. HV Battery module is made up with multiple battery cells connected in series.

A fully charged cell voltage is a little over 4 Volts and empty little over 3V.

There are 18650 cells inside battery pack. Cells are cylindrical in shape with 18mm diameter, 65mm length/tall and 47 grams weight. Cell stores up to 3500 mAh. Cells can be charged as high as 4.2V and discharged as lows as 2.5V.

Values are different depend on battery generation/model. Please contact us to get to know more for your model.

Cell Material: lithium-ion

 

BMB Module

It is located outside the battery pack. Some of components could be corroded because of moisture/water ingress and it get bad connection.

6. Labor Cost

Labor cost could vary depend on type of workshop, location. If you are looking for best affordable Tesla independent workshop. Please free to contact us Call/Whats App +49(0)15226242038 or find best affordable workshop in our Workshop Locator

6.1 Labor Cost in Authorised Service Center

It could cost labor rate per hour * Flat Rate Time. Labor rate per hour could vary depend on location. However it could cost in between 175 - 275 euro/dollars per hours. Flat rate time could vary depend on work. If you would like to know Flat Rate Time for particular work. Please contact us.

6.2 Labor Cost in Independent Workshop

It could vary depend on type of workshop, city/region/country etc.

Please have a look on some of most common repair/services prices Price List

9. HV Battery part number (details)

Model	Year	Part Number	Part Name
S
X
Y
3

Part number could vary depend on model year, region etc. If you need help to find/order correct part for your car. Please free to contact us Call/Whats App +49(0)15226242038

Remote Support

In case, if you have any question or need any support/help. Please feel to contact us Contact Us or Call/Whats App +49 (0) 15226242038.

Find, compare and Book workshop to Fix it

If are you looking for best workshop who is expert to perform such repair/services with good prices. You can find and compare hundreds of Tesla independent workshops. Please feel free to contact us. We will be happy to organize an appointment with workshop. Please find best workshop through our Workshop Locator

Book an Appointment

If you would like to book an appointment in best affordable workshop. Please book an online appointment.

Buy New/Used Spare Parts

If you would like to buy spare parts. Please have a look in our catalog or Contact Us Phone/Whats App +49(0)15226242038

How to remove and replace

Alert Code

Some of most common possible alert code.

You might have received one of following alert.

BMS_f003, BMS_w003

• BMS_f003_HW_Module_Alarm
• BMS_w003_HW_Module_Alarm
• The battery management system (BMS) has detected that one or more of the battery modules has reported an alert. This alert may be set falsely at extremely low

BMS_f017, BMS_w017, 

• BMS_f017_SW_Brick_OV
• BMS_w017_SW_Brick_OV
• The battery management system (BMS) has detected that a brick is reporting a voltage above the maximum acceptable cell voltage.
• Potential Impact Inability to

BMS_u018

• BMS_u018_SOC_Imbalance_Limiting
• The battery managed system (BMS) detects a condition internal to the high voltage (HV) battery that requires it to limit the maximum allowed brick voltage.

BMS_a018

• BMS_a018_SW_Brick_UV
• Alert Description The battery management system (BMS) has detected that a brick has fallen below the minimum brick voltage.

BMS_w021

• BMS_w021_SW_Dr_Limits_Regulation
• Alert Description The battery management system (BMS) limits power because the pack current, pack voltage, or brick voltage, is outside of the expected bounds.

BMS_u025

BMS_a079

Please contact us for more details.

BMS_w090

BMS_f097

• BMS_f097_HW_BMB_Under_Voltage
• A battery monitoring board (BMB) reports a brick under voltage event, indicating that the BMB has detected a brick voltage lower than the minimum allowed brick
  

BMS_f098

• BMS_f098_HW_BMB_Over_Voltage
• A battery monitoring board (BMB) reports a brick over voltage event, indicating that the BMB has detected a brick voltage higher than the maximum allowed brick

BMS_f107, BMS_w107

• BMS_f107_SW_Cell_Voltage_Sensor
• BMS_w107_SW_Cell_Voltage_Sensor
• Alert Description The battery management system (BMS) detects a brick voltage measurement that is inaccurate.
• Please contact us, we will provide you more details about this alert and how to fix/reset.

BMS_a146

• BMS_a146_SW_Brick_Overdisc  
• The battery management system (BMS) has detected that a brick is over-discharged. Potential Impact: Inability to charge, drive, or support the low voltage (LV)

BMS_W163

• The battery management system (BMS) has detected that contactors have undergone stress from a wide-open throttle (WOT) event.

BMS_w164

• BMS_w164_SW_Brick_SOC_Imbalance
• The battery management system (BMS) detects a state of charge (SOC) imbalance between bricks associated with the same module.

BMS_w165

• BMS_w165_SW_Module_SOC
• The Battery Management System (BMS) detects a state of charge (SOC) imbalance between modules.
• Potential Impact: No expected impact on vehicle functionality.

BMS_w166

• BMS_w166_SW_AhToBeCharged_Imbal

BMS_W173

• BMS_w173_SW_Brick6_Sense
• The battery management system (BMS) has detected battery monitor board (BMB) brick 6 voltage sense inconsistencies.

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.

Do not repair only Battery Pack, Do Preventative Battery Repair

If you open the HV Battery. It could be good to check couple of things as preventative maintenance, most common issues in particular HV Packs, so HV Battery will be in good condition for next couple of years (Kilometers) and customer does not worry for next couple of years. 

You should repair all possible causes.

Please feel to contact us. We will be happy to provide you info/list what could be checked. 

Donation/Support

If you feel you have benefited from this guide. Please consider donation, which will help us to create more such free guide for you. It will also show us that this guide was helpful for you. Click on "Donation"

Repair Shop Owner/Mechanic

If you are workshop owner/mechanic and offer Tesla Repair/Service and would like to add your workshop in our list. Please have a look in our Become a Partner Page or contact us.

For Mechanic/DIY Expert

There are some car owner who like to buy spare parts from OEM or Aftermarket and prefer to do Mobile Service, DIY or need support. If you would like to offer this services to car owner in your region. Please contact us. 

Comment

Please leave us comment if you have any questions, if you would like to add/edit/delete some content in guide, if you would like to have guide on any another topic etc.

Share this guide Link

Please feel to share this guide/website link.

FAQ

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.

Can I do it/repair yourself/myself (DIY)?

Some of repair could be done at DIY. In case, if you needed Tools, Know-How, Time etc. Please feel to contact us. We will be happy to provide you online 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.

Mobile repair service?

In some of cases, 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.

Car under warranty?

In case if your car is under warranty. It is recommended to perform certain repair works (HV Components, ADAS etc) with OEM during warranty period. Wear and Tear Part Repair could be done with independent workshop to save money. Please read more details in another guide. Link 

How HV Battery can fail?

There are numbers of reasons.

Some of common most common reasons are 

• water ingress 
  • It could come through different ways. Please feel to contact us to know which ways. 

Pressure Test

My Tesla car shows 0 range?

There may be many reasons for this issue. Please feel to contact us. We will be happy to help you. 

Case 1: One of customer replaced module in HV pack and car showed 0 range. He contacted us. We provided him remotely solution and issue got resolved. Please feel to contact us. We will be happy to provide you solution. 

Which Tools do need to repair high voltage battery repair?

Need battery bench, which could hold around 1000 kg. HV Battery could wight around 600 kg.

Gloves, PPE, Safety Glasses, Isolated Tools. You could check tools from KamasaTools