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Running Tesla Model 3's computer on my desk using parts from crashed cars

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Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#121

Post by colechristensen »

bluGill wrote: post #27

I used to work for a company that made third party scan tools. We had racks of ecus disconnected from the car with just a diagnostic connector and power. nothing got to a real car without first trying it on the rack. I remember on time we figured out a bmw (pre obdii) had the bytes offset from the standard documentation (it was a semi-standard protocol that some other cars used at the time), we went from we communica…

I spent the last week successfully reverse engineering my car / various scan tools to get the right information to diagnose a fuel pump problem (and to do so without the incredible awkwardness of many of the tools)

It's pretty amazing what Claude + Ghidra + knowledgable coaching can accomplish. It was basically just setting direction, setting up an incremental workflow with the right kind of documentation, and questioning some of its theories and assumptions from time to time.

I'd love to release a lot of it but I'm torn between releasing artifacts created with expensive software I paid for and thinking that many of those things should really be freely available to anyone (specifically the things which definte the protocol to talk to the car and mapping of what various things are reported vs what they actually mean.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#122

Post by SecretDreams »

longislandguido wrote: post #58
kube-system wrote: post #13

> Turns out that actual cars don’t have individual cables. Instead they have these big “looms”, which bundle many cables from a nearby area into a single harness. This is the reason why I could not find the individual cable earlier. They simply don’t manufacture it. I was really surprised to read this at the end of the article -- how could someone be this deep into a project of this depth and not realize this?! Not o…

Software people tend to overestimate their knowledge of other disciplines, writing it off as "easy" or work beneath them. Being overpaid compared to your peers certainly doesn't help dispel this feeling. Some people have built entire careers around designing wire looms.

It's called misplaced confidence and it isn't exclusive to software engineers. Doctors, engineers, presidents... The list goes on.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#123

Post by killjoywashere »

desmondwillow wrote: post #96
longislandguido wrote: post #58

Earlier quoted context omitted.

Software people tend to overestimate their knowledge of other disciplines, writing it off as "easy" or work beneath them. Being overpaid compared to your peers certainly doesn't help dispel this feeling. Some people have built entire careers around designing wire looms.

Consider whether this is an uncharitable comment --- someone with little expertise in a discipline has made a rookie mistake and didn't realize that the wires weren't produced individually. Professionals overestimating their knowledge is a very common thing!

Fair, but software engineers are especially known for this. There was an XKCD about it

https://xkcd.com/1831/

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#124

Post by nishanseal »

This is awesome. Curious if these are plug and play and if that's the case where is the memory that tells you what the mileage is. If it's attached to the computer than the mileage would be off if you switch/repair it.

Completely unrelated. Would be interested if you figure out how to retrofit the new adaptive shocks on performance models to the older cars. Something I would love to do if I had hobby time. I'm pretty sure they fit physically, but needs to be connected to the main computer. I likely would never touch the main computer unless I got root access. In my brain I was thinking about a separate system made with raspberry pi's.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#125

Post by Rohansi »

a-dub wrote: post #83
sneakymichael wrote: post #67

Earlier quoted context omitted.

Interesting take–– I feel the total opposite; I love the UI.

i think a lot of people do. i don't know what it is, there's maybe just something about the car graphic that doesn't sit right with me. the front/side view when parked just seems cheesy for some reason. maybe because it's meant to show unclosed doors or something and when everything is set the car's status is car which is redundant.

It does show open doors etc. but if not that then what would you show on the screen? You can already shrink it so the rightmost 3/4 of the screen is the map, leaving just 1/4 of the screen for the car visualization and indicators.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#126

Post by jandrese »

Onavo wrote: post #79
kube-system wrote: post #13

> Turns out that actual cars don’t have individual cables. Instead they have these big “looms”, which bundle many cables from a nearby area into a single harness. This is the reason why I could not find the individual cable earlier. They simply don’t manufacture it. I was really surprised to read this at the end of the article -- how could someone be this deep into a project of this depth and not realize this?! Not o…

EVS have actually managed to reduce the number of wire bundles (mostly due to switching to Ethernet instead of CAN Bus)

Tesla also went to a 48v wiring harness in some of their vehicles to allow them to power more equipment with less copper. It might be one reason why they use nonstandard connectors, so people don't attempt to hook 12v equipment to the system and also the higher voltages might require connectors rated for it.

Now they just have to take the next step and have everything in the vehicle running on PoE.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#127

Post by tclancy »

colechristensen wrote: post #121
bluGill wrote: post #27

I used to work for a company that made third party scan tools. We had racks of ecus disconnected from the car with just a diagnostic connector and power. nothing got to a real car without first trying it on the rack. I remember on time we figured out a bmw (pre obdii) had the bytes offset from the standard documentation (it was a semi-standard protocol that some other cars used at the time), we went from we communica…

I spent the last week successfully reverse engineering my car / various scan tools to get the right information to diagnose a fuel pump problem (and to do so without the incredible awkwardness of many of the tools) It's pretty amazing what Claude + Ghidra + knowledgable coaching can accomplish. It was basically just setting direction, setting up an incremental workflow with the right kind of documentation, and questi…

Wait, why wouldn’t you post it/ write it up?

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#128

Post by a-dub »

Rohansi wrote: post #125
a-dub wrote: post #83

Earlier quoted context omitted.

i think a lot of people do. i don't know what it is, there's maybe just something about the car graphic that doesn't sit right with me. the front/side view when parked just seems cheesy for some reason. maybe because it's meant to show unclosed doors or something and when everything is set the car's status is car which is redundant.

It does show open doors etc. but if not that then what would you show on the screen? You can already shrink it so the rightmost 3/4 of the screen is the map, leaving just 1/4 of the screen for the car visualization and indicators.

maybe it's the quasi-photorealistic nature of the car image that bothers me. it's not a photo, it's not a schematic, it's not a diagram. it's too artificial to look like a photo, yet too realistic to look like a schematic. or maybe the physically implausible lighting.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#129

Post by xyzzy123 »

varenc wrote: post #99

From the article > Tesla offers a “Root access program” on their bug bounty program. Researchers who find at least one valid “rooting” vulnerability will receive a permanent SSH certificate for their own car, allowing them to log in as root and continue their research further. Pretty interesting. Sounds like Apple's Security Research Device Program[0], where you're loaned a rooted iPhone, but with a clear qualificati…

Having shell is extremely handy for further discovery. SO handy that if they were just gonna patch the bug and lock you out, you would simply not disclose it.

Re: Running Tesla Model 3's computer on my desk using parts from crashed cars

#130

Post by Reason077 »

incrediblylarge wrote: post #92
juleiie wrote: post #84

Earlier quoted context omitted.

What happens?

A professional scientist I know (tenured, professor) recruited me to set up a backtesting framework for a predictive finance model. When the results were not as they expected (this person does not work in finance and never has), they asked to see the code, then told me that claude had found a problem with the way some of the calculations were done (there was actually no problem), supplied the claude comments, and tol…

This sounds rather similar to the form of scientific fraud where you first create a conclusion, then invent/manipulate the data until it supports your conclusion.
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