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2022 Model 3 LR.(Salvage vehicle) HV Battery contactors not closing due to crash event in VCfront

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Hello smart Tesla motors club folks,

I would be grateful if anyone can read/ comment on this post and help me fix this.

I have 22 Model 3 (Production date 01/22 & SW version 2022.28.2) with the new Li-Ion 12v battery design. Got the vehicle from auction with airbag deployed.

The M3 is about 90% fixed now. Also, performed the following:

1. Replaced blown Pyro fuse.
2. Airbag fixed & RCM reset - complete.
3. Bought new Li-Ion 12v battery - currently supported by a 12-16v supply source to prevent damaging LV Li-Ion battery.
4. Already have Toolbox 3 access.

Currently have the following faults:

VCFRONT_a191 Electrical system power reduced
VCFRONT_a192 Electrical system is unable to support all features
VCFRONT_a478 Schedule Service – Vehicle may not restart
VCFRONT_a402 Electrical system backup power is unavailable - Vehicle will consume more energy while idle
HV Battery contactors not closing. Sometimes they close but they open after a bit of time.

I am experienced person who likes to work on electronics/ Tesla diagnoses. As we know, the 22 M3 and MY with new 12v Li-Ion design have a technology where if the car gets in a accident/ airbag deploys, the VCfront will receive a crash event on the memory. We also know that on newer SW/Firmware vehicles, a clear post crash load can be initiated from service mode or Toolbox 3 and those faults above might go away (assuming you have new 12v Li-Ion battery), and HV battery contactors will close.

I tried to update the car to SW 2023.2.10 so I can get the Clear post crash load option on the new firmware; SW download stops at 75%. Why? Any reasoning? I tried doing it again and again 5 times, but it would always stops at 75% download (not even installing yet), See picture. I need your help so I can perform clear crash load after. Maybe help me in how to update VCfront to the new SW/FW?

I know there is a thread named: Salvage 2022 Model Y LR. High Voltage Battery contactors not closing. Car has the new Li-Ion 12v battery. I read all the comments.
Note: I know I can buy a new VCfront, just deploy SW and fix it that way. The point of this post is to collaborate together to come up with new ideas/ way to install a newer FW/SW on a VCfront with crash event. There has to be a way. I can even take the VCfront out of the vehicle and connect it to a laptop, just need your help in a method to deploy SW on it.
 

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Hello, I also have a 22 M3.
I’ve done everything you have so far.
My update is also stuck at 75%.
I’m debating if I should buy a new VCfront.
My only concern is, if I do get a new one from tesla. Do I need toolbox to calibrate it or program it to the vehicle?
 
The main problem that I see here is the software version 2022.28 it came with many issues, I had a similar situation in my model 3 and a friend of mine in his model S as well and we both had to send the cars to Tesla SC to manually push the update to each module one by one, my understanding this is a feature available only at Tesla SC not available in the Toolbox (If anyone knows how; please share).
However try redeploy the software but keep to connect all modules, headlights, taillights, for some reason that might prevent software updates (happened to me before and I had to redeploy again after connecting all lights and modules and worked fine)
 
I do really appreciate your statement:
The point of this post is to collaborate together to come up with new ideas
Being on that canva, can you guy give me more details about:
We also know that on newer SW/Firmware vehicles, a clear post crash load can be initiated from service mode
  1. Do we know a set of things that are possible to be done from service mode ?
  2. Do I understand correctly that by service mode is about pushing MCU GUI into service mode?
 
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1. Yes lots of this are now possible in the service mode.
2. See


But on vehicles with post crash load shed, usually service mode doesn’t load, and you either need to use Toolbox to clear that flag, or replace the vcfront.
But even with replacing the VCfront withe new one; most likely you will need the ToolBox to redeploy the software updates to get the car to recognize the new hardware
 
Does this software redeploy approach also be valid for action like:
  • traction inverter change? after old drive unit got broken
    or
  • performing RCM reset?
It's valid for any new/used hardware connected to the car for the first time, like Headlights, foglights, any module, etc... but not for RCM reset.
However, for the drive unit, you will need to perform different functions through the ToolBox only; you can search for it through the ToolBox functions (can't recall what is the name)
 
Hello smart Tesla motors club folks,

I would be grateful if anyone can read/ comment on this post and help me fix this.

I have 22 Model 3 (Production date 01/22 & SW version 2022.28.2) with the new Li-Ion 12v battery design. Got the vehicle from auction with airbag deployed.

The M3 is about 90% fixed now. Also, performed the following:

1. Replaced blown Pyro fuse.
2. Airbag fixed & RCM reset - complete.
3. Bought new Li-Ion 12v battery - currently supported by a 12-16v supply source to prevent damaging LV Li-Ion battery.
4. Already have Toolbox 3 access.

Currently have the following faults:

VCFRONT_a191 Electrical system power reduced
VCFRONT_a192 Electrical system is unable to support all features
VCFRONT_a478 Schedule Service – Vehicle may not restart
VCFRONT_a402 Electrical system backup power is unavailable - Vehicle will consume more energy while idle
HV Battery contactors not closing. Sometimes they close but they open after a bit of time.

I am experienced person who likes to work on electronics/ Tesla diagnoses. As we know, the 22 M3 and MY with new 12v Li-Ion design have a technology where if the car gets in a accident/ airbag deploys, the VCfront will receive a crash event on the memory. We also know that on newer SW/Firmware vehicles, a clear post crash load can be initiated from service mode or Toolbox 3 and those faults above might go away (assuming you have new 12v Li-Ion battery), and HV battery contactors will close.

I tried to update the car to SW 2023.2.10 so I can get the Clear post crash load option on the new firmware; SW download stops at 75%. Why? Any reasoning? I tried doing it again and again 5 times, but it would always stops at 75% download (not even installing yet), See picture. I need your help so I can perform clear crash load after. Maybe help me in how to update VCfront to the new SW/FW?

I know there is a thread named: Salvage 2022 Model Y LR. High Voltage Battery contactors not closing. Car has the new Li-Ion 12v battery. I read all the comments.
Note: I know I can buy a new VCfront, just deploy SW and fix it that way. The point of this post is to collaborate together to come up with new ideas/ way to install a newer FW/SW on a VCfront with crash event. There has to be a way. I can even take the VCfront out of the vehicle and connect it to a laptop, just need your help in a method to deploy SW on it.
I'm in the same boat.
2022 MY 4/22 has 12 V LI batt that will not charge. Bought one on Ebay Darn it is 16Vy
Not hearing the HV contactor close
 
I'm in the same boat.
2022 MY 4/22 has 12 V LI batt that will not charge. Bought one on Ebay Darn it is 16Vy
Not hearing the HV contactor close
First of all you can change those LI lvb they don't usually need to be replaced. BMS in them will shut it down under 11V maybe 12 so they don't ever actually get totally discharged unless sitting for a really long time. Replaced your Vcfront?
 
First of all you can change those LI lvb they don't usually need to be replaced. BMS in them will shut it down under 11V maybe 12 so they don't ever actually get totally discharged unless sitting for a really long time. Replaced your Vcfront?
Usually salvaged cars sat on auctions for long enough where the LV battery needs replacement. You can test by checking voltage between the small pin that is closest to the center of the battery and the negative battery terminal. If that voltage is below 9V then you need to replace the battery.