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BMW PHEV: Safety fuse replacement is extremely expensive

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Re: BMW PHEV: Safety fuse replacement is extremely expensive

#421

Post by labcomputer »

nandomrumber wrote: post #138
mvkel wrote: post #130

This is what makes Teslas sustainable and other car cos, like Porsche, not. A battery pack for a Model 3 is $10K. So even if the whole car is only worth $20K, it's still worth keeping on the road. The Porsche Taycan battery pack is $70K. The moment you have any issue at all with it, the car will be considered totaled.

Is that $10k the list price, or have you actually seen a recent invoice from a mechanic for a Model 3 battery swap?

I have no info on Tesla batteries. But, just as a point of reference, you can now buy knock-down 48V battery "kits" from China for under $90/kWh. They include everything you need: case, cells, BMS, circuit breaker/isolator, and fire suppression. Assembly takes about an hour. (The raw prismatic cells without the rest go for ~$50/kWh).

Shipping from China to the west coast runs an additional $30/kWh due to the weight of the cells and volume of the box (shipped in several boxes to reduce cost). So you can have a 300 lbs, 15 kWh 48V battery shipped to your door for about $120/kWh).

High voltage EV batteries need additional components (like HV contractors) due to stacking so many cells in series, but it seems entirely plausible that Tesla's economies of scale allow them to offer a 75 kWh battery for $10k (~$133/kWh) plus installation.

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#422

Post by idiotsecant »

prepend wrote: post #336

It’s funny how I extrapolate car design sessions in my head based on software design sessions. I sold my bmw after 15 years of multiple bmws because their design is so poor for maintenance. I had cooling system problems that required hours of labor to get to just to replace a plastic part that cost $5 where an aluminum one would cost $7. It seems to me that bmw was designing for best case scenarios where everything g…

Management only cares about analyzing and completing the 'happy path' because customers only buy 'happy path'. Customers don't (with rare exceptions) buy 'unhappy path', even though statistically it is a near certainty that where they will find themselves at some point.

I guarantee no engineer wanted an expensive, difficult to replace pyro fuse. Unfortunately, it doesn't particularly matter what individual engineers want, it's what the system wants, and the system wants to make money.

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#423

Post by BigGreenJorts »

BobaFloutist wrote: post #410
Gravityloss wrote: post #378

Earlier quoted context omitted.

Porsche had a research program about a very reliable car in the 70s. It has some odd technical choices from today's perspective. https://www.hagerty.com/media/automotive-history/when-porsch... One would assume taxi companies etc would be willing to pay for cars that have high uptime and reliability. But I think they drive mostly the same stuff as regular people. At least one would assume they could get beefier suspen…

I don't think it's a coincidence that an enormous number of rideshare/delivery drivers drive priuses though. Reliable, not too expensive, low maintenance, and high mpg is kind of exactly what you'd expect them to look for.

Not to mention still roomy!

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#424

Post by mikepurvis »

PeterStuer wrote: post #388
prepend wrote: post #336

It’s funny how I extrapolate car design sessions in my head based on software design sessions. I sold my bmw after 15 years of multiple bmws because their design is so poor for maintenance. I had cooling system problems that required hours of labor to get to just to replace a plastic part that cost $5 where an aluminum one would cost $7. It seems to me that bmw was designing for best case scenarios where everything g…

My last 4 cars were BMW. I love the way they drive, but ... I think they are optimized for the EU leasing market. 4 years, 120.000km. If you buy one for long ownership and want more out of them (they can most certainly do 400=500k km reliably), you have to take care of them from day 1. You change the maitainance schedule (which by default is set to lowering fleet lease costs and who cares beyond that), learn about an…

I was looking for this reply as well; definitely my perception that a lot of mid- to high-end cars are engineered to drive and feel great for 4-5 years, and after that it's kind of a crapshoot. You can see it as well with the various subscriptions, for app connectivity, M2M infotainment data, etc— all of it is oriented around that same time horizon.

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#425

Post by Glawen »

jinzo wrote: post #335
Glawen wrote: post #289

Earlier quoted context omitted.

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

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.

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.

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#426

Post by bdangubic »

SoftTalker wrote: post #93
pests wrote: post #58

Earlier quoted context omitted.

When my buddy got his first Tesla back in 2018 he had a ICE rental for some reason and he left it running in the driveway all day once on accident.

The complete lack of awareness with which some people operate cars never ceases to amaze me.

lol - quite amazing!

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#427

Post by notjonheyman »

BobaFloutist wrote: post #410
Gravityloss wrote: post #378

Earlier quoted context omitted.

Porsche had a research program about a very reliable car in the 70s. It has some odd technical choices from today's perspective. https://www.hagerty.com/media/automotive-history/when-porsch... One would assume taxi companies etc would be willing to pay for cars that have high uptime and reliability. But I think they drive mostly the same stuff as regular people. At least one would assume they could get beefier suspen…

I don't think it's a coincidence that an enormous number of rideshare/delivery drivers drive priuses though. Reliable, not too expensive, low maintenance, and high mpg is kind of exactly what you'd expect them to look for.

The only slight pain in those priuses is removing the windshield wiper assembly to get to the spark plugs closest to the firewall. It's not like they didn't have enough room in the engine bay to the left to better engineer this. But it's something that you rarely have to do. Maybe 2-3 times for the life of the car if it reaches 300k+ miles.

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#428

Post by bdangubic »

l1tany11 wrote: post #70
bdangubic wrote: post #24

Earlier quoted context omitted.

as long as you don’t compare them to any car. teslas in 2025 belong in a museum lol I own tesla s 2014, my neighbour has 2025, same car. tesla x was cool… in 2017. tesla 3 is like a worse looking kia and model y is like if you took tesla 3 and pumped some air in it.

2025 S is the same as your 2014 S? That’s some hilarious cope. Stop lying. You know it’s completely different. Yes, a model S is still a model S. And the F150 is still a pickup truck. Surprise!

2025: https://www.kbb.com/tesla/model-s/2025/

2014: https://www.kbb.com/tesla/model-s/2014/

If this was like “find 5 differences game” you’d lose :-)

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#429

Post by sublimefire »

somerandomqaguy wrote: post #140
consp wrote: post #123

Earlier quoted context omitted.

It is a BMW problem and the rest is clickbait. If you own a BMW you know all this as it has been the case for over decades. It's also not a eu thing as all manufacturers are locking things up, Ford and other US brands are trying as much as all other manufacturers. They just haven't reached BMW levels yet.

UN Regulation No. 155, and 156, and the Cyber Resilience Act (CRA) are requiring car manufacturers to implement cryptographic validation that allows only authorized software from the manufacturer to be run.

This is just signing, nothing cutting edge. Verification of signatures is a fairly old tech. What is the exact problem here? Is it that manufacturers do not publish the signed binaries or is it that you want to run something on your car compiled by you?

Re: BMW PHEV: Safety fuse replacement is extremely expensive

#430

Post by ErroneousBosh »

hnburnsy wrote: post #27

If you love cars or Top Gear, watch Mat Armstrong on YouTube. Mat restores crash damaged cars. The BS he has to go through because car manufacturers either won't sell him parts, won't sell him repair manuals, and unnecessarily cryptographically lock parts to the VIN is sometime heartbreaking. He has run across this pyro fuse issue many times. Sometimes he has even has to buy two cars just to repair one because of thi…

Meanwhile, if you work on old Landrovers from the Defender 90/110 to early RR L322, you need this: https://rangerovers.pub/downloads/rave.zip (500MB zip, PDFs of all service and user manuals).

Even if you don't work on them, grab yourself a copy. You never know when you might need to know how to rebuild a Borg Warner transfer box or ZF 4HP24 gearbox.

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