> Vehicle manufacturing is ruthlessly optimized. Vehicle manufacturers wouldn’t add complexity to common systems if it didn’t pay off.
You make it sound as though this intended to be a benefit to the consumer or the end product. Having worked on and around cars, and being friends with people who do for a living, I am really unconvinced that the manufacturers do a lot of this for any consumer-friendly reason, rather than simply trying to squeeze a buck out of you.
I can absolutely tell you that Volvo, for example, does what the GP is talking about, and then some. On an old school GM or Toyota, if you break a simple switch or knob, or things that really should just be simple devices, you can just pull it out, go to the junkyard or a parts retailer, and put the new one in and be on your way. Not so for Volvo (and I'm sure this has caught on in other manufacturers): if your switch or control or whatever fails, and its hooked up to the CAN-bus, whatever replacement you find simply won't work until you've gone to the dealership (if they even let you use a part that didn't come from there at all) and gotten them to flash the part and whatever other crap needs flashing like a BCM to get them to be compatible (I think just flashing the serial number of a BCM or whatever it needs to play nice with to the switch), at the tune of a couple hundred or more dollars each time.
So in essence, a stupid simple part, that should have been $5-10 that the manufacturer likely never would have seen a dollar from in the aftermarket, is now a $200+ dollar flash at the dealership, using the manufacturer scan tool, and also increasingly requires only parts the manufacturer can generate. So no, I really am extremely skeptical, given what occurs *today* that 95+% of the junk on CAN bus is there for any reason other than to boost dealership and manufacturer profits for no other reason than the fact they can.
Building with one bus is just easier. It's not some nefarious end goal.
It's like putting everything over IP (VoIP, video over IP, audio over IP, etc.) and then just running Ethernet throughout your building. From an engineering perspective, it's just way easier. Routing wires -- on a circuit board, in a building, in a car, in anything -- is just a real PITA.
Now it's definitely true that having to flash something on the CAN bus to make it work is possibly due to greed, but the original idea of putting things on one bus is not.
> You make it sound as though this intended to be a benefit to the consumer or the end product. Having worked on and around cars, and being friends with people who do for a living, I am really unconvinced that the manufacturers do a lot of this for any consumer-friendly reason, rather than simply trying to squeeze a buck out of you.
The "consumer friendly" part is competing on price; they don't care about repair cost, in fact parts for repair is just recurring revenue on top on (till before pandemic) slim margins on selling the car
Isn't that what's supposed to happen in capitalism? Everyone working is getting paid, supply matching demand, prices reducing and ostensibly zero profit for established sectors.
I never got the impression the previous poster was saying this is a benefit for consumers; he's saying it's for the manufacturer, to cut costs.
Edit: that being said, all your points are completely valid.
I own a vehicle built in 1981. I can absolutely assure you that CAN is better for consumers. People seem to forget the two-inch thick bundles of wires, the hours spent tracing one turn indicator cable, the insulation of the cables in the middle starting to rot and things shorting out, water getting trapped in bundles, failures modes including stuff melting inside the dashboard from high-current stuff all being wired back to a central place... I could go on.
After my recent sample n=1 (2015 Honda), I'm left wondering how much mechanic griping is due to a lack of engagement with digital systems rather than a hard lack of ability.
I bought a $20 OBD2/J2534 cable, downloaded an easily-available ["pirated"] copy of Honda HDS, and seemingly had access to all the functionality a dealer would have. From looking at the Honda website, I could have paid by the day/week/etc for official access to flashing tools or the newer iHDS, which I might have needed for a newer car.
If I had wanted to reflash any of the modules, I probably would have wanted a better cable (though it's hard to know if module manufacturers really have such shoddy update processes that interrupting the flashing can really brick a device, or if that's just persistent superstition like so much in the car world). But I was able to replace the VSA/ABS module and perform the necessary "dealer reset" procedures no problem. I just wish I had obtained this setup before I went about misdiagnosing the problem based on a document that claimed to be the OEM service manual but actually wasn't. Luckily the part I misdiagnosed did end up being the problem!
Of course, I would love for there to be some sort of mandate for manufacturers to document the details of all CAN messages. Because there don't seem to be that many different module manufacturers, they must all be working to some kind of internal standards for their own interchange, and end-user visibility into computing systems is critically necessary for preventing computational disenfranchisement where people see these systems as impenetrable black boxes. But it feels at least in Honda land, much of that capability is practically available to the repair market (at least as of 2015 model years). One just needs to get over the activation energy of setting up the OEM software tool.
Good example. Do you know of anywhere that Volvo parts pairing / programming issue is written up or documented?
I'm working on Right to Repair and we get asked for examples like this from various government agencies all the time. It would be very helpful, thanks!
If you're looking for informal evidence, there's plenty of posts on SwedeSpeed and Volvo Forums (and probably Turbo Bricks, for those masochists that own a post-RWD car) bemoaning needing to constantly reprogram tons of things like door switches, and the various lengths owners and enthusiasts will go to in order to attempt to overcome these issues.
If you're looking for something a little more formal, I think the factory service manual probably calls out that the R&R on a ton of parts will involve reprogramming. I no longer own any post-Ford Volvos nor do I have any interest in European cars, so unfortunately I don't have any newer FSMs. A way you might be able to get at one on the cheap is to pick a popular model/year later Volvo (maybe like a 2016+ XC60?), and get a subscription to the make/model/year on Alldata (which was something like $20 a year for just a single combination), or hunt for an FSM on eBay, if it's old enough to still have a paper FSM.
My friend's 2016ish VW jetta straight up uses proprietary bolts and shit in it. He and I are the type to do all our own car maintenance but his car has pushed my patience beyond anything I've seen prior...
Dad used to rebuild and repair late model Volkswagens, and I got a first hand taste of what it's like servicing those. German cars are the absolute worst, especially in this regard. Everything little plastic piece is hundreds of dollars when it breaks, and it all had to have been installed by German contortionists. Need to do something on the engine? Better get if on the lift, because the whole front cradle needs to be dropped out from the bottom of the car if you want to get it done in anything short of a glacial pace. Vag-Com is an expensive and irritating piece of kit, maybe only second to Vida Dice (Volvo) in terms of level of frustration sometimes.
There's no way I would ever recommend someone who wanted to keep their car past the first 50 or so thousand miles ever buy a VW or a VW with slightly shinier wallpaper (Audi). There's a reason the service techs on those and BMWs get paid well, and why they're often hated by mechanics.
"they can be expensive, but you can buy them" seems to be a very surface-level view here.
Say I only need to replace a $5 switch as the parent poster suggests. My options then are pay $200 to the dealership to flash and install it (if they'll even flash a third party part) one time, or I can pay thousands of dollars for a tool I'll use once and do it myself.
That isn't a real choice, and the auto makers are adhering to the letter of the law but not the spirit of the law. Which is legal for them to do, but it doesn't make it any less scummy.
Ford I believe now requires a subscription for diagnostics but I haven't seen anything about per VIN charges yet. I'm not sure about the British or Japanese brands either. This is AFAIK regardless of dealership or independent shop.
Gm is $40 per VIN 1 year,
Chrysler is $35 for flashing but to do that you need 2 more subscriptions which totals about $120
There are aftermarket tools but the subscriptions are for a year and about $1000-$4000
The problem is as I always point, that people want complexity and technology for everyday but as soon as something breaks they want it to be like 1990.
The article complains about CAN bus not being secure but this sort of attack is very rare, you need special tools, skills, physical access to the network and time. Regular car thieves don’t go and make a key to steal a car, that would be the same as a 1980’s one breaking a window and start trying to decode the cylinder and then cutting a key!
How does a towing company get your car in 10 seconds? That’s how they’re stolen most of the time.
God damn. I swear if they could , they would make you buy a fucking new wrench every time you work on a different car. Such bullshit how they tie their tools to a per-vin registration.
this is much more about insurance companies only paying for cheaper 3rd party parts for repairs than it is anything anti-consumer, though I'm sure there's some of that, too.
the automotive parts industry is massive and if you allow third party parts manufacturers to make parts for your car, you are undercutting your own parts replacement business. how do you counter that? you require that replacement parts come from you. the only way to do that is via electronic means, because anything purely mechanical can (and is) reverse engineered quickly.
insurance companies fight against this in court because 3rd party parts are much cheaper than official parts, and usually come with an associated dip in quality as well, which is another reason auto makers fight for first-party parts businesses.
Honda doesn't want Snake Oil Autoparts stuff installed on cars which are still under warranty after a collision, for example, but the insurance company paying for those repairs definitely does.
> you require that replacement parts come from you. the only way to do that is via electronic means, because anything purely mechanical can (and is) reverse engineered quickly.
They lost the right to require things to do with thr car the
y sold the car.
Electronic lockouts will be cobsidered theft one day
> They lost the right to require things to do with [the] car they sold the car.
not if you want a warranty or any manufacturer support on the vehicle at all, and these are things that consumers value a lot.
> Electronic lockouts will be [considered] theft one day
among the most feverish people, they are considered a problem worth fighting, which I agree with, and I don't think it will ever be considered theft. the law just doesn't support electronic lockouts as theft, and precedent on this would be very difficult to undo without changes to laws defining what ownership actually is.
There are also long-standing legal requirements for automakers to be separate from car dealers, which also translate into making the repair/diagnostics equipment available.
yes. the same law (or, rather, the movement at the time within congress) is what standardized the OBD-II connector and mandated its inclusion in all cars from 1996(?) onwards: the idea that consumers should be able to repair their own big-ticket items should they choose to.
You make it sound as though this intended to be a benefit to the consumer or the end product. Having worked on and around cars, and being friends with people who do for a living, I am really unconvinced that the manufacturers do a lot of this for any consumer-friendly reason, rather than simply trying to squeeze a buck out of you.
I can absolutely tell you that Volvo, for example, does what the GP is talking about, and then some. On an old school GM or Toyota, if you break a simple switch or knob, or things that really should just be simple devices, you can just pull it out, go to the junkyard or a parts retailer, and put the new one in and be on your way. Not so for Volvo (and I'm sure this has caught on in other manufacturers): if your switch or control or whatever fails, and its hooked up to the CAN-bus, whatever replacement you find simply won't work until you've gone to the dealership (if they even let you use a part that didn't come from there at all) and gotten them to flash the part and whatever other crap needs flashing like a BCM to get them to be compatible (I think just flashing the serial number of a BCM or whatever it needs to play nice with to the switch), at the tune of a couple hundred or more dollars each time.
So in essence, a stupid simple part, that should have been $5-10 that the manufacturer likely never would have seen a dollar from in the aftermarket, is now a $200+ dollar flash at the dealership, using the manufacturer scan tool, and also increasingly requires only parts the manufacturer can generate. So no, I really am extremely skeptical, given what occurs *today* that 95+% of the junk on CAN bus is there for any reason other than to boost dealership and manufacturer profits for no other reason than the fact they can.