1. Introduction
This is generic alert. There could be many reasons for this alert.
BMS_w172 is an external isolation warning. One of High Voltage components (excluding high voltage battery) has too little resistance between HV Components and chassis ground.
In most of cases, it could be issue with battery coolant heater, Large Drive Unit, A/C Compressor, Fuse etc. however other HV Components could be faulty.
The best way would be do isolation testing to find out the exact faulty components.
2. How to Diagnose
This alert could come because of one or more system/feature is disabled/faulty. It need to check additional alerts to find out the cause of this alert.
It could be possible to find out the exact cause via Remote Diagnosis, Service Mode.
2.1 How to check additional alert
It could be possible to find out exact cause via Remote Diagnosis, Service Mode.
2.2 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
2.3 Service Mode
It could be possible to do self diagnose via Service Mode.
How to read service alerts in Service Mode
- On the touchscreen, click Controls > Software
- Touch and hold the large word "MODEL" for 2 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 diagnosis) Link
In case, If you need support for diagnosis. Please Connect Us.
If you need support. 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.
3. How to Fix it
Some of alert could come because of software bugs. Some of alert could resolve after restarting the system, software update/reinstall. In some case, car might need hardware repair.
3.1 Restart Touchscreen
Restarting the touchscreen could resolve the issue.
- Shift car into park.
- Hold down both scroll buttons on the steering wheel until the touchscreen turns black.
- Wait approximately 30 seconds for the touchscreen to restart.
Please read more details in another guide (how to do). Link
3.2 Powering Off the Car
If restarting the touchscreen have not resolved the alert/issue. You could try Powering Off the car.
- Please shift car into park
- On the touchscreen please touch Controls > Safety > Power Off
- Please wait for at least for two minutes without interacting with the car. Please do not open the doors, touch the brake pedal, touch the touchscreen etc.
- After 2 minutes, please press the brake pedal or open the door to wake the car (Source Tesla)
3.3 Software Bug
One of reason could be problem with software bug. Updating latest software version might solve the issue. Please read more details in another guide. Link
3.4 Coolant Heater
One of reason could be that coolant heater. Please check more details about possible alert code, how to check, how to repair etc in another guide. Link
3.5. AC Compressor
Please check out more details about about A/C Compressor repair. Link
3.6 Fuse
One of reason could be that fuse is blow up.
3.7 Drive Unit
In case if you have Model S/X with Large Drive Unit. It could be issue with coolant leakage.
Cost
Cost could vary depend on issue, type of workshop, location. If you are looking for online support or affordable independent workshop. Please free to contact us or have a look in Price List
Online Support
In case, if you have any question or need any support/help. Please feel to contact us Contact Us or Whats App +49 (0) 15226242038
Find, compare and Book workshop to Fix it
If are you looking for best workshop who is expert to fix such issue with good price. Please contact us we will be happy to organize an appointment with workshop or find, compare and book best workshop in Workshop Locator
Book an Appointment
If you would like to book an appointment.
Book an Appointment to Fix an affordable Workshop
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
Alert Code
Possible alert code
1. BMS_w172
BMS_w172_SW_Drive_Iso_Warning
The battery management system (BMS) has detected low isolation conditions during multiple drive cycles.
In case if you have Model S/X and got BMS_w172 together with BMS_u008. In most cases, it could be issue with Coolant Heater, Compressor, Fuse
Please send us "Service Alert" Screenshot via Contact or Whats App +49 (0) 15226242038. We will be happy to help to fix alert.
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.
For Repair Workshop Owner
If you car repair workshop owner and would like to add your workshop in our list. Please contact us.
For Car Mechanic
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.
Frequently Asked Questions (FAQs)
