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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

#41

Post by denysvitali »

rconti wrote: post #34

I _do_ find it weird that the LCDs from crashed cars are so expensive. I wonder if newer models have better screens, so people with older cars upgrade? Or if they're a common failure point? I have a Model 3, but I can't say I follow the forums.. but I've never heard of screens failing -- I'm sure it happens but I think if it was common problem I'd have heard of it.

Some newer models have better (bigger) screens, and some are incompatible since they've slightly changed the connector. Old models (pre highland/ jupiter facelift) have used the same display shown in the article for a very long time across M3 and MY. What usually happens is that they physically break because people are not that careful, so the touch screen ends up breaking - although you really have to put a lot of force to break that display.

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

#43

Post by kube-system »

MBCook wrote: post #37
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…

I will say I’m surprised how far apart the two boxes are in the car. I guess they’re not where I thought. I would assume they’re both up near the dash.

The passenger side kick panel or behind the glove box are two very common places for vehicle computers -- some cars have them under the hood, which I always thought was a bad idea.

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

#44

Post by spuz »

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…

Even if you know that cars consist of a single wiring harness, it's not implied that they aren't modular and the individual cables cannot be purchased separately.

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

#45

Post by mixdup »

AlotOfReading wrote: post #20
ferongr wrote: post #4

Earlier quoted context omitted.

>then I needed to find a brake controller that can work with the higher voltage (14.4v vs the normal 12v) Put a voltmeter on the battery terminals of a regular car at 2000rpm and note the voltage. You'd be surpised (the alternator can produce as high as 15V on some cars).

Automotive transients can be wild. I did a bringup with a board that had specified 100+v range specified for transients and finicky quality requirements on the output. The power supplies took up most of the (very large) board.

14v is not a transient, if your voltage was 12v with the car running, there's something wrong with the charging system (DC-to-DC in an EV, alternator/generator in an ICE)

13-14v is normal in all 12v automotive systems as the charging voltage

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

#47

Post by [deleted] »

spuz wrote: post #44
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…

Even if you know that cars consist of a single wiring harness, it's not implied that they aren't modular and the individual cables cannot be purchased separately.

[deleted]

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

#48

Post by a1o »

> A DC power supply capable of providing 12V

Hey, I just remembered my school used to have ages ago some cool power supplies (I think from Agilent?) that were very idiot proof, they had current limit with a dial that I think didn’t went over 1A or perhaps even less, and they would instantly disarm on short circuit (and indicate it with a led), and also the voltage dial I think wouldn’t go over 25V. I remember it was very big and heavy, but it survived countless students that used the lab daily.

Nowadays, is there any power supply available that is that resistant or is the recommended approach to get an used old one? Does anyone have a power supply at home that is also used by kids with a brand/model they would recommend? Thanks!

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

#49

Post by kube-system »

spuz wrote: post #44
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…

Even if you know that cars consist of a single wiring harness, it's not implied that they aren't modular and the individual cables cannot be purchased separately.

Cars usually consist of multiple harnesses -- as it is in this case as well. The harnesses are the cables in a car. That is the part you can purchase because that is the part.

There's a list of them here: https://service.tesla.com/docs/Model3/ServiceManual/2024/en-...

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

#50

Post by guyzero »

Congrats, OP has recreated a test/development bench, the bane of developers working on automotive software development all around the world. They're so close to being a real vehicle that you think you'll be able to get a lot of work done, but they're not, so you don't.
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