Comment by jinzo
12 hours ago
Is it insane? I'm working in this field, and I know how quickly you can come up with such a number if you are BMW and you are deathly afraid that someone will get electrocuted while working on your car, driving it or rescuing someone in a crash. It's a safety and liability issue, where they go to great lengths to actually re-certify a battery after crash. The whole thing is setup so, that even the dummy electricians in an average BMW shop can safely certify that this battery is still safe. It's a lot easier to kill yourself (or someone else) when working on a EV Battery than wet belt. Also a lot harder to repair said battery than wet belt. And that goes for all EVs and manufacturers that actually care about people (Tesla, demonstrably does not).
If you and BMW are correct - if we take it for a fact that a simple fender-bender can make batteries develop life-threatening faults, which absolutely require a 4k euro inspection that involves complete disassembly and specialist equipment, then that means that EVs are unsuitable for public use.
So either all EVs need to be scrapped forever, or BMW needs to engineer a more tractable solution to the problem, or BMW is overreacting and overcharging customers.
No, from my experience, a simple fender-bender does not cause this.
In the article, it was mentioned that the issue can be caused by hitting the curb, there's a guy in the comments who says his VW grenaded itself this exact way just while charging (luckily his car was in warranty).
Yeah, that's OP's point then, that a fender bender causing this is an overreaction from BMW
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Yes, it is insane. It's a fuse. They must have some stats on how often those things need replacing and it should have been accessible. The customer has - when they buy the car - absolutely no way of knowing what kind of surprises like this there are hidden in the vehicle and besides, it kills the second hand market so you can only trade your vehicle to a BMW dealership where they can absorb those costs for a fraction of what it will cost an end user. BMW is a crap brand in spite of their reputation, we've had one leased Mini in our company and it is the very last time we do business with BMW, that thing was more in the shop than out of it with electrical issues. A friend had pretty much every BMW ever made since he got wealthy enough to afford them (car enthusiast) and his experience is much the same, but he keeps buying them.
They have no stats because the entire platform is new and different. I would guess they have a very poor prediction model.
It’s not a fuse. It’s a fuse plus guarantee plus liability.
> It’s a fuse plus guarantee plus liability.
This is BMW we're talking about. Their guarantees are worth absolutely nothing if my experience is anything to go by and them accepting liability is not something you should have to pay 4K for if other brands can do the same thing under $100.
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> It’s a fuse plus guarantee plus liability.
If that was the issue you wouldn't be allowed to change your wheels on the side of the road. They'd be locked down to the car and require a complex software procedure to guarantee they were swapped correctly and won't endanger lives.
This is a professional shop raising the issues. They are liable for how the repair is done. BMW is just liable to lose money if people can easily fix their car at some other, cheaper, professional garage.
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Fuses are not items that should be replaced normally - they are self-destroying emergency protections for the electrical system.
If it is protecting that end users can plug arbitrary loads into, that is one thing - but this doesn’t sound like that?
Why did that fuse blow? Because if that is not addressed, it’s likely to just blow again.
I think the people that replace fuses are aware of the potential issues around them. The article - which I'm sure you've read so don't take this as commentary on your comment - details that in other electric vehicles, for instance Tesla this is handled quite differently:
"While Tesla’s pyrofuse costs €11 and the BMS reset is around 50€, allowing the car to be safely restored, BMW’s approach borders on illogical engineering, with no benefit to safety, no benefit to anti-theft protection — the only outcome is the generation of billable labour hours and massive amounts of needless electronic/lithium waste."
It's not a choice between 'ridiculously inaccessible with the potential to create more damage than your car is worth' and 'push to reset'. There are many options in between, some of which would be a happy medium between the two that protect both safety, the environment and the customers' wallet. Which BMW's solution clearly isn't.
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This fuse blows because a crash was detected and it is to protect the people inside the car and rescuers. The article argument is that it can blow even for small crashes where no damage to the battery occurs but rehabilitating the vehicle still incurs an outrageous cost. This is not a simple over current protection fuse.
$1000 for the module with the fuse seems ok to me. Another $3000 to link the module to the vehicle is the outrageous part.
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> Fuses are not items that should be replaced normally - they are self-destroying emergency protections for the electrical system.
Next time when the fuse switch in my home I'll buy new home. I shouldn't normally switch on auto-fuse again!
Fuse blows, so you know something went wrong, you check corresponding part, fix it, and enable/change fuse. Nothing special. In home perspective - it could be plugging too many energy needy receivers into one outlet.
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Ladies and gentlemen - behold the perfect consumer
The article gave examples for why the fuse blows - it falsely thinks the vehicle was in an accident and trips. Hitting a pothole or a rabbit.
It is unlikely to blow again under normal use.
Then why name it a goddamn fuse then?
Yep, might be there was a known issue that was addressed, at which put in a new one. But just replacing a fuse (or, simultaneously worse and better, just resetting a breaker) without further investigation is just kicking a very spicy can down the road.
I had a doozy of a trip issue on one project, a motor would occasionally (not always, no real pattern, hot/cold/etc. didn’t matter) trip the breaker, requiring a sparky to come out and open up the panel to reset it. We tried a bunch of things, megger-ing the motor, testing peak startup current on each phase with a fancy meter, checking phase-to-neutral current (Larger than you’d think! But this was normal, apparently.)
Everything was normal. In the end all we could think something was weird about the contactor. They took it out (I was off site at the time) and took it down to the substation to test it out.
With three phases connected to the contactor (and nothing connected on the other side) they energised the coil, and with an almighty bang it tripped the main incomer and took the entire sub offline.
Turns out there was a manufacturing defect in the contactor and sometimes for a millisecond, if the phase of the moon was right, it dead shorted two phases.
So there, even when you know everything, you don’t know everything.
Fuses are necessary on any electrical system, and especially in a car, which is an electrical shitshow (floating ground, high-voltage and high-frequency interference), fuses blow all the time. Granted, usually on a well-maintained and new car it happens very rarely, but saying that it's a catastrophic and concerning event is dumb.
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Many people drive older cars worth less than £4000.
Sticking to old/cheap cars seems like an increasingly good option with so many scare stories about the pain and extreme expense of getting modern cars, particularly EVs, repaired.
And the impending ban on new ICE vehicles seems likely to lead to more older cars being kept on the road for a lot longer.
My current car is my last. It's a 1997 and it runs pretty much as good as new and I expect the thing to outlive me.
Depends on the parts situation. As someone who works on my own cars I've become increasingly distressed at the car parts industry. Even OEM parts, when they are still available, seem to have had a dramatic decrease in quality over the past couple of decades. This is even assuming the correct part is shipped in the first place, which is another problem that has become entirely too common, especially in an age where everything is computerized. So many times you get a box with the correct part number on the outside but the wrong part inside.
If you have the parts and the will it's possible to keep any car running close to forever. That said if you've gotten to the point where the frame is totally rusted out then maybe it's time to consider moving on.
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Yeah - a car hits a similar valuation around ~15 years of age, meaning a failure of this component limits the financially viable lifespan of a car to this amount - mechanics do engine rebuilds for less money.
ICE bans are going to cause the value of old cars to skyrocket
Yes, it's insane. People working in the field have their perception warped by what they see around them.
I mean, I don't think my perception is warped by what I see. But by "am I willing to risk that my repair will kill someone, because they wanted cheaper repair"? Or even if not kill, maybe just burn down their car (+ house,...). "Am I willing to use cheap tools, not rated for 800V (or 400V) god knows how many Amps?". Because this is not software development - you can be killed REALLY quickly working on a HV EV battery pack. It's no joke. For sure it'll cost more than working on a regular car, where there is danger, but a lot less. And that's just the basic thinking, without going deeper into why its more expensive to repair stuff like this.
The article and comment aren't debating whether the fuse plays an essential role. There's no reason to make the process of fixing the issue after a minor incident expensive, extremely convoluted, and very prone to error.
Making it a very complicated and expensive fix isn't what's saving your rescuer or mechanic from getting electrocuted while working around your car.
> There's no reason to make the process of fixing the issue after a minor incident expensive, extremely convoluted, and very prone to error.
Yes there is. Either nobody is engineering towards that aspect or it is a conscious decision, deliberating between two different buckets: bill-of-material cost per unit and estimated impact on your warranty & goodwill budget. Whatever is deemed to be cheaper will win.
Source: I work at an automotive OEM and one of my first projects almost two decades ago was how to anchor after-sales requirements into the engineering process. For example, we did things like introducing special geometry into the CAD models representing the space that needs to be left free so a mechanic can fit his hands with a tool inside. These would then be considered in the packaging process. If you consider these are two completely different organizations, it becomes a very tricky problem to solve.
It's like the manufacturer discovering to their complete surprise they are building a car. :-D
> BMW refuses to provide training access for ISTA usage
Refusing access to training isn't a BoM issue by any means. Neither is a repair process that's so error prone that it can do even more damage to the car. We are surrounded by evidence that manufacturers in every field are taking decisions that are hostile towards their customers in the chase for profits. With the rise of EVs with far fewer moving parts needing constant maintenance, the manufacturers had to shift to different revenue streams, like killing repairability and locking everything behind manufacturer approval.
This is a professional shop voicing the complaints, not a random guy trying to do a fix on the side of the road.
Imagine someone told you they work for Apple and the reason everything is soldered, glued, stacked in a way it will never survive disassembly, and every bit of software and hardware in the device needs the manufacturer's blessing to be replaced or just keep running is because it was cheaper and safer this way.
> it becomes a very tricky problem to solve.
It was a solved problem for everything mechanical where locking it down or preventing people from learning wasn't really an option. How did it become tricky again just now when we deal with far more flexible software and possibility to lockdown?
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You seem to be ignoring the fact that the battery pack status after a crash is essentially unknown. It should go through a thorough and competently conducted safety inspection or it may kill someone in the future. Of course, this doesn't excuse extra red tape tacked into the procedure, but the core idea of an inspection is just unavoidable.
> Of course, this doesn't excuse extra red tape tacked into the procedure
That's exactly it. I understand the importance of safety but reading the list of complaints I just cannot believe that safety is the key driver for the design decisions.
> ISTA’s official iBMUCP replacement procedure is so risky that if you miss one single step — poorly explained within ISTA — the system triggers ANTITHEFT LOCK.
> Meaning: even in an authorised service centre, system can accidentally delete the configuration and end up needing not only a new iBMUCP, but also all new battery modules.
> BMW refuses to provide training access for ISTA usage
Everything about this screams greed driven over-engineering. Since when are error prone processes and lack of access to information better for safety?
We live in a world where everyone justifies taking user hostile actions with some variation of "safety". Software and hardware are locked down, backdoored, need manufacturer approval to operate even when original parts are used, etc.
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You, you are the problem.
It's not excusable to do this to the product because of some hand wavey napkin math about liability.
Understand how people will interact with your product and then use that information to avoid doing things like routing power where firefighters want to cut and you'll accomplish the same thing without a stupid expensive hair trigger fuse.
I am a problem, but on the other spectrum - OEMs ain't getting the repair €€€ because people like me repair stuff (but a different approach than Vanja).
Then, almost no manufacturer that sells in the EU knows how to do this (Renault is almost the only one that doesen't have pyrofuses in the battery, almost everyone else has). The catch is, the routed power is not problematic, the problem is when something gets squished and redirects that routed power to somewhere else. Which tends to happen in a metal tincan.