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Comment by qwertox | Hacker News Reader

From the referenced video "CT Wilson: the delegate blocking Right to Repair in Maryland" [0]: "You don't need the source code, to change your battery, ...".

I'm somehow confronted with this with my VW car. The battery is close to dead, and I want to replace it. I can do that. Yet the car needs to be informed that it now has a new battery in order optimize its power management (it's not an electric car, it's basically the most simple modern VW).

I need to go to the dealer and have them change the battery for me and reset the battery status, which is maybe 100€ in addition to the battery cost.

If the source code would be publicly accessible, probably a cheap OBD-2 adapter would be capable of doing this.

[0] https://www.youtube.com/watch?v=ej1MmjCPYqU&t=197s

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For that specific issue, you don't need the source code, you need the dealer diagnostic/programming toolkit. Hyundai GDS, BMW ISTA, each manufacturer has their own but I believe they're mostly reskinned and customized 3rd party products (I think Mazda & Ford have a shared toolkit).

These give you everything from the service manual (detailed info on how to do any repair operation, with steps and photos), diagnostic code scanning and guided troubleshooters, and access to the car's electronics for putting ECUs into service mode (like the electronic parking brake) or reprogramming them with updated firmware (which is complicated and you probably don't need to do it). The service steps will interface with the car's ECUs - if you need to change the transmission fluid, the software will prepare the transmission, help you get it up to temperature and maintain that temperature, and then reset the calibration of the transmission at the end. And it'll show the technician each mechanical step they have to do along the way. Very advanced stuff.

You can generally get this software a normal person, but it's a expensive subscription:

https://hyundaitechinfo.com/ https://bmwtechinfo.bmwgroup.com/

You can usually find cracked versions online, but recently they've been getting more and more locked down.

As for your battery replacement thing, there are 3rd party phone apps which can do it. You'll just need a compatible OBD adapter. I don't know what it is for VW, but for BMW BimmerLink gives you diagnostic info and lets you reset the battery, and BimmerCode lets you change some config options in the car ECUs to enable some useful small QoL features. I'm sure there is similar software for VAG cars.

I don't know for the most recent versions but until recently there always was a button configuration on all Fords which does this without obd adapter. Requires a bit of searching but there are plenty of forums describing it. The combinations might differ per model though.

Al that DRM also makes it neigh impossible to self service your car these days.

> For that specific issue, you don't need the source code, you need the dealer diagnostic/programming toolkit.

Presumably the source code to that toolkit would be just as good, and having access to the car's source code would let you build your own toolkit.

from hundred dollar hardware and software license to "just put this image on your raspi"

GP doesn't personally want the source code, they're saying if it was available there would likely be an open source and/or cheaply available third-party toolkit so they wouldn't need the (probably unobtainable?) manufacturer's official one intended for dealers.

> If the source code would be publicly accessible, probably a cheap OBD-2 adapter would be capable of doing this.

Buy an OBDeleven or VCDS if you own a VW and are doing any work on it yourself.

You can also adjust features (roll up windows with remote, etc). Run diagnostics in real time while driving, test every switch/sensor on the car. Also, it is needed if you do a brake job on the rear brakes to open/close the parking brake so you can put the pads in.

I don't believe you need to recode the battery if you replace with the exact same battery but you need to change it if you don't put in the OEM one [1]

Yeah we don't have the source code. But with long coding adaptations in the system you can do a large portion of what you need to do (engine/trans swaps). If going deeper is needed there are companies who reflash/recode ECUs but that is about as deep as you can go without doing independent module hacking.

[1] https://youtu.be/48w9Cg4ObEk

Are car batteries smart now? How would your car know what brand of battery you put in?

Added the video that explains it in the edit above.

If you put in the same battery it isn't an issue. You need to recode if you change the size or type.

LiFePO4 batteries that you'll find in some vehicles (more often than not for running accessory loads, not starting the engine - though some models are intended for dual purpose use) usually have a decent degree of intelligence baked into an on-board BMS system.

Typical car batteries are not yet so 'smart'. The post-battery-swap 'coding' that many euro vehicles need is to instruct the car-side BMS about the battery's characteristics so that it can tune things like its start-stop routine, alternator behavior, etc. to optimize battery life and resilience.

Any VW-approved diagnostic tool can recode the battery. Allegedly (I haven't personally had need to try it yet) the ODBEleven (https://obdeleven.com/en/) can do so.

It IS incredibly silly that you need a specialized tool to code the new battery, but unfortunately that's the direction the auto industry seems to be going.

Yes OBDEleven can code the battery in your VW.

> It IS incredibly silly that you need a specialized tool to code the new battery

It's not silly. It's ridiculous that car manufacturers abuse their customers this way. And people wonder why I stick with old cars.

If you need an entire application to reset a battery status (btw: why is that even needed?) the problem is with the process of resetting the battery status, not with having the source code of the application. Why is there not a simple procedure like pressing a button or a combination of buttons or a menu in the radio?

I can partially explain this since I've had to do this in the past. You have to program the BMS for the specific chemistry and capacity of the battery you install. It's not a reset. 99% of the time you don't even need to reprogram the BMS. But a lead, SLA, AGM, and Rolls have different properties. Like you couldn't replace a lead acid with a lithium ion battery because the charge algorithm could destroy the new battery.

Finally, cars are doing a lot more with the onboard starter battery. Or in case of hybrids, a lot less. A modern car is never truly off once the key is out. The BMS will need to know the real capacity of the battery so it can reserve enough charge to start the car.

If the car is able to disconnect it's starter battery, and can start up and run just fine after a disconnect, why does it need to be powered up at all when the car is off? What's so important for the car to do, that it can sit there draining the battery, but still be happy to completely disconnect the electrical system to preserve a startup?

At a minimum and at its most benign, it has to power sensors to detect key commands when you get near it, or functions like keeping the headlights on for a while after you lock it (usually branded "follow me home" or similar). There are probably more debatable things like checking for OTA updates or sending sensor data to some online services.

Mostly driver convenience. I drive a mid-tier VW with infotainment, power seats, satellite navigation, etc. If I don't drive the car after a few days it takes a few minutes for the car to fully boot up. No radio, GPS, climate control goes full blast, and it won't know what my power seat settings are. Now imagine having to do that every time you pull the key out, run in the supermarket, and go back to the car.

We're demanding a lot from the car battery lately and the BMS needs to know where it stands.

I know how a BMS works and I kind of understand why a reset is needed, but to replace a battery with a new one of the same characteristics (capacity, chemistry etc) should need a very simple reset procedure with no external tools. With the modern displays in most of the cars, you can put that in a menu there.

I am still riding a motorcycle with no battery and kickstarter. That is the ultimate reliability and dependability, the last thing you want in the middle of the mountains is the vehicle to stop because it does not have the latest monthly Windows update for .Net framework that works only OTA and there is no signal in that area. I am exaggerating a bit, but only for artistic purposes :)

Driving battery replacement to the authorized dealer network, when combined with various up-sell charges that they concoct some reason to tack on and it represents a very significant profit opportunity. It has nothing to do with the actual BMS and they aren't particularly interested in optimizing anything but their sales/service funnel.

So at this point the battery needs to come with a QR code on a piece of paper that, once installing the battery and starting the car then entering some service mode, you can hold in front of the backup camera so the car can read in the characteristics of the battery, eh?

Fine, but why do you need a special tool to reprogram the BMS? The car should have a "reset" button or something built into it that you can trigger when needed to accomplish this.

Yes. Why not have a texeditor for a config save file in the radio?

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