Hi,
I'm currently considering purchasing a Model S 70D with a faulty battery and 180k km.
Firstly, I want to precise that I have extensive experience in electric vehicle maintenance and battery repair. I've worked on dismantling full batteries from vehicles like the Opel Ampera alias Chevy Volt, rebuilt custom battery packs for French PSA EVs, and worked on various other EVs using Tesla modules or others battery types. I'm equipped with the necessary tools, experience, and qualifications to work on high-voltage (HV) systems.
While I'm confident in my skills, I'm relatively new to Tesla vehicles and am seeking information to diagnose this car as accurately as possible before making a purchase.
The primary issue appears to be an HV isolation problem, likely due to water ingress into the battery pack. The current faults displayed are: bms_f123, bms_w035, bms_w073, bms_w123, and other GTW faults.
I haven't yet obtained the BMS_isolationResistance value, but I do know that all x14 battery modules are well-balanced (16mV difference) at around 3.95V (via scanmytesla app).
Before purchasing and potentially removing the battery pack for inspection, I'd like to be around 80-90% certain about the location of the issue.
I can perform any necessary checks on the car tomorrow. I have a PEAK CAN adapter on hand and access to the vehicle CAN bus under the MCU. I perfectly know that the bms_f123 issue is significant and can't be reset without a full battery isolation check. However, if I'm correct, and if the isolationResistance measured by the BMS is above 1MOhms when contactors are open, it might be worth resetting the error to determine whether the isolation issue truly originates from the battery pack or from another HV device like the heater.
I'd greatly appreciate any tips or guidance to diagnose this car correctly.
Thank you.
I'm currently considering purchasing a Model S 70D with a faulty battery and 180k km.
Firstly, I want to precise that I have extensive experience in electric vehicle maintenance and battery repair. I've worked on dismantling full batteries from vehicles like the Opel Ampera alias Chevy Volt, rebuilt custom battery packs for French PSA EVs, and worked on various other EVs using Tesla modules or others battery types. I'm equipped with the necessary tools, experience, and qualifications to work on high-voltage (HV) systems.
While I'm confident in my skills, I'm relatively new to Tesla vehicles and am seeking information to diagnose this car as accurately as possible before making a purchase.
The primary issue appears to be an HV isolation problem, likely due to water ingress into the battery pack. The current faults displayed are: bms_f123, bms_w035, bms_w073, bms_w123, and other GTW faults.
I haven't yet obtained the BMS_isolationResistance value, but I do know that all x14 battery modules are well-balanced (16mV difference) at around 3.95V (via scanmytesla app).
Before purchasing and potentially removing the battery pack for inspection, I'd like to be around 80-90% certain about the location of the issue.
I can perform any necessary checks on the car tomorrow. I have a PEAK CAN adapter on hand and access to the vehicle CAN bus under the MCU. I perfectly know that the bms_f123 issue is significant and can't be reset without a full battery isolation check. However, if I'm correct, and if the isolationResistance measured by the BMS is above 1MOhms when contactors are open, it might be worth resetting the error to determine whether the isolation issue truly originates from the battery pack or from another HV device like the heater.
I'd greatly appreciate any tips or guidance to diagnose this car correctly.
Thank you.