[jacquesm]

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.

[prepend]

They have no stats because the entire platform is new and different. I would guess they have a very poor prediction model.

[seec]

Well, he buys them for the same reason people buy Apple products: very performant, look good, and carry a lot of social status.

Otherwise, they make some very questionable engineering decisions for sure. On their motorbikes, you often have to disassemble half the bodywork just to change the battery; that's just beyond stupid. But like Apple, their products are kind of unique, so people deal with it.

[tengwar2]

BMW bikes have improved. It used to be with the last of the dry clutch flat twins that when the clutch failed (and it would fail), you had to remove the back half of the bike. Literally. As in not figuratively, to avoid doubt. The front half would be left standing, like some bisected cow artwork. Apparently it was a two day job.

[jacquesm]

Funny, I posted a pic to exactly that further down in the thread.

[seec]

I mean, they are generally excellent motorcycles. Their monocylinders are super smooth with great handling.

But often you have to deal with those weird engineering decisions that make repairs annoying. My local garage is a BMW car specialist, and it appears that it's basically the same deal.

Funnily enough, in my youth I visited the BMW factory in Munich, and I was amazed back then. But the maintenance fails to amaze as much, haha.

[lazide]

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.

[jacquesm]

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.

[bradfa]

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.

[jinzo]

They are not only linking it to the vehicle, they are doing a LOT of other checks on the battery - that it's not damaged in non-obvious ways. For that you need trained people (it's really high voltage and amperage stuff), tooling AND you really need to be sure you guarantee everything is OK.

Even the basic mechanical disconnect and lowering of the battery is far from simple (and requires A LOT more expensive tools than changing a wet belt - not because they are greedy, but because a lift that can lower such hevy battery costs a lot of money, mostly in materials), and that's not even opening it, making sure you don't get electrocuted when you work on it ect.

[20after4]

The lift costs about as much as one of their repair bills. That can hardly justify the cost.

[taneq]

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.

[11mariom]

> 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.

[lazide]

That is literally exactly what I’m saying.

In that situation, if you bypassed the fuse, or just kept replacing them without figuring out why it blew (too much load on a specific circuit), you very well might burn your house down by catching the wiring inside your walls on fire.

If it’s something that it is easy to connect loads too, then that is probably not super unusual and easy to fix, because people do that all the time, and you know what is happening and how to fix it. But you do need to fix it.

If it isn’t, then that is very concerning, because something caused that overload, and without that fuse your wires would have caught on fire instead of the fuse blowing. Inside your walls.

Either way, fuses are an emergency measure to stop the wires from destroying themselves from overload. They are destroyed in the process of saving your wires.

And if you are doing this all the time? You’ve got a very big problem brewing.

[torginus]

Ladies and gentlemen - behold the perfect consumer

[potato3732842]

Then why name it a goddamn fuse then?

[prepend]

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.

[kristjank]

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.

[jinzo]

This is a pyrofuse, it does not blow with overcurrent as regular fuse, but blows in the same way airbags blow - when detecting a crash. We can debate if they blow too quick, but if you are designing this system - where and truly lives can be in danger, you would probably err on the side of caution too.

[LorenPechtel]

The problem is not that the pyrofuse blows. Safer to be paranoid when it's the the battery pack. The insanity is what it takes to replace it, including throwing away perfectly good parts because of the anti-theft protections.

[idiotsecant]

Pyrofuse will definitely blow on overcurrent.

[jacquesm]

Usually not by itself though, and if it does that makes it a hybrid fuse, one that has both a pyrotechnical disconnector and a thermal/overcurrent one.

[lazide]

What sort of cars do you drive?

I’ve never had a fuse blow on a car less than 20 years old, and then it was due to shorts due to damaged insulation and bad grounds due to corrosion, which are legit problems that need to be corrected.

Also, unlike breakers, fuses are generally immune to issues with HF interference and the like - they work through basic thermoelectric effects which iron out all but the most extreme issues. If you’re moving multiple amps in a situation described as ‘RF’, or ‘high frequency’ in a DC system that’s not just noise!

That’s a real problem that needs fixing!

Not fixing the underlying problem behind a blown fuse (or constantly tripping breaker) is how your car (or house or whatever) burns to the ground.

Or you have a Lucas, in which case my condolences.

[kristjank]

I'll grant you that, I had a lot of beaters. A typical thing was that a lock solenoid pulled too much current in cold weather and consistently blew the central locking fuse.

[taneq]

It’s not a fuse. It’s a fuse plus guarantee plus liability.

[jacquesm]

> 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.

[monegator]

They'll refuse warranty on the XDrive if you don't use approved brand and model of tyres so... my bet is on them wanting to extort all the precious money they can from their poor customers

[OptionOfT]

They'll refuse warranty if the difference between thread is too much between front and back as that causes wear of the clutches. Just like you should have the same tire on the same axle.

Or if the tires are not the right size, especially in staggered setups.

If you come from a car that is FWD with AWD capabilities, it doesn't matter as much.

But BMW (at least the ones with the engine mounted longitudinally) which have xDrive are permanent AWD.

[petre]

This is why the Chinese brands will eat their cake.

[jinzo]

I'm sure it depends on market, but I also know 100% that if they will certify the battery as safe, and then you get electrocuted when entering your car because the battery was not safe - they will be on the hook, in all developed markets. No one else, that cares about people safety, do the same thing for under $100. Even Tesla, that almost completely disregards any safety - be it "Full Self Driving" or "let's just change this, without checking if the battery is actually safe", does not do it under $100.

[Glawen]

Do you realise how difficult it is to get "electrocuted" in a battery powered vehicle ? I suggest you document yourself on the matter.

The only real issue in reality is thermal runaway

[amelius]

Yeah, what is the max voltage of these batteries?

[jacquesm]

Depends on the brand and the model, there is a trend towards higher voltages because that implies lower currents and wiring is heavy and expensive.

It started out with (nominally, voltage can rise and fall based on charge levels) (30S) 144V packs, (96S) 352V is very common and there are (192S) packs that do 704V (but that are marketed as 400V and 800V respectively).

You don't want to get zapped by any of these, it's middle voltage DC which is quite dangerous, so the fuses definitely have a safety aspect in case of a crash, they are to protect emergency personnel from touching the frame and exposed wiring. But that's in case of a very serious crash, your average encounter with a rabbit might set off the crash detector (which can't really know ahead of time how bad a crash will be) but has extremely little chance of resulting in exposed wiring. In the case of BMW that rabbit could end up being pretty expensive.

[jinzo]

What are you talking about? Yes I know how quickly I can get electrocuted when the battery pack is open. I just need to touch two exposed busbars ~30cm apart. Or my tool needs to touch them.

[Glawen]

Exactly, you need to touch both plus and minus. You moved the goalpost from getting electrocuted driving your car due to shoddy quality remanufacturing of battery, to getting electrocuted while repairing the high voltage side of your vehicle. Remanufacturing quality does not come into play if you decide to touch plus and minus side of a HV battery.

[Tostino]

I disagree with your other takes in this thread, but you are 100% right here. This is dangerous stuff that needs to be treated with respect.

I don't think it should be locked away to just the MFG, but it does need to be respected.

[ricardobeat]

They mention in the article that replacing the same fuse on a Tesla cost €11.

[jacquesm]

Given that I've tried to hold BMW to their warranty and was shafted I would not bet on that.

[semanticist]

There's a difference between BMW ignoring their warranty and who gets found liable during the wrongful death lawsuit after the mechanic gets electrocuted due to poor/unsafe EV design.

I'm sure BMW would love to not be liable in those cases if they could just decide not to be liable, but inspections and fuses presumably turn out to be cheaper than the settlements they'd otherwise be paying.

[close04]

> 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.

[jinzo]

Yes, as changing a tire is completely the same tool-and-knowledge level than repairing a EV Battery.

If you would see how EV Clinic "repairs" Tesla batteries, you would not say they have any concern for liability.

[close04]

> Yes, as changing a tire is completely the same tool-and-knowledge level than repairing a EV Battery.

I think you are intentionally misrepresenting this and moving the goalposts to make your point. GP blamed safety and liability for the way the process looks like, not the complexity of the task. When it comes to safety you bet that an improperly installed or inspected wheel or tire can be dangerous.

A short internet search tells me [1][2] that some sort of tire malfunction causes tens of thousands of accidents and kills hundreds of people every year in the US alone. That doesn't include wheel malfunctions (e.g. wheel coming off). Yet this isn't locked behind some manufacturer approval and proprietary tools.

How BMW chose to approach this is profit driven. The old money printing machine from ICE maintenance, repairs, and spare parts is slowing down so they come up with new ways of extracting money. Like making the lives harder and more expensive for any non-BMW shop to do repairs. They're not alone in this, other brands do the same.

> If you would see how EV Clinic "repairs" Tesla batteries, you would not say they have any concern for liability.

More moving of goalposts mixed with not understanding what liability is, and where it belongs. So you tell me what's Tesla's liability when EV Clinic "repairs" a battery.

[1] https://www.smithlawcenter.com/practice-areas/defective-tire...

[2] https://www.safetyresearch.net/nhtsa-gets-real-on-tire-fatal...

[jinzo]

> I think you are intentionally misrepresenting this and moving the goalposts to make your point. GP blamed safety and liability for the way the process looks like, not the complexity of the task. When it comes to safety you bet that an improperly installed or inspected wheel or tire can be dangerous.

Sorry that you feel that way, it was not my intention. But improperly installed or inspected wheel or tire is A LOT less dangerous than crashed EV Battery. And in EU you have a lot of effort going even into this, Police can inspect (and does) the tire from the outside (+ regular mostly yearly MOTs). All new cars have to have pressure sensors in the tire. So I would say EU (where EV Clinic is present) is making a lot of the same strides to make everything around tires safer. And believe it or not, if you go buy any new car in EU, drive it 5 minutes and swap the wheels yourself, it'll flag an error! As the wheels need to have appropriate pressure sensors - that also need to be programmed into the vehicle for a lot of makes.

You think it's profit driven, I don't. Agree to disagree.

> More moving of goalposts mixed with not understanding what liability is, and where it belongs. So you tell me what's Tesla's liability when EV Clinic "repairs" a battery.

I was aiming at EV Clinics liability, not Teslas. And I can guarantee you that both Tesla and BMW take into consideration the bad press if someone, even non official mechanic, repairs their cars and then they kill someone/catch fire. Of course Tesla a lot less than BMW, I even have a feeling that this contributed more to how BMW does things, than profit.

[close04]

I posted some links with data. You still think that improperly installing the only thing that keeps a speeding car on the road is not dangerous? You disagree even when the data is provided so that sets the bar for what your disagreement means.

BMW has manufactured engines and cars for over a century and historically they were relatively easy to fix by anyone. Their image in the press never suffered because of bad unofficial repairs.

All of this is trying to find a retroactive explanation that fits the result when the real reason is staring you in the face: they make money by making the owner entirely dependent on BMW as much as possible.

Your explanations are flimsy and disproven by data or history.

[jandrese]

Improperly installed wheels that have fallen off of vehicles in motion have killed not only the occupants of the vehicle but pedestrians and other motorists (especially motorcyclists) in the past. We also allow people to fill vehicles with highly combustible fluids with little to no oversight, which has caused fires and deaths.

There is a certain level of risk that is inevitable with moving multi-ton machines at lethal speeds, and deciding that this particular issue is where we are going to draw the line is dubious.

The point that "allowing this fuse to be replaced affordably is too much of a safety issue" is a cop out is valid.