Have fun trying to troubleshoot something that uses a controller of some sort .vs fuse system without thousands of dollars of equipment.
Really... have fun. I rather check the fuses and trace the wiring for that part using a meter.
“Why does a car like the Tesla still have old-style fuses?”
51–60 of 72 posts
Re: “Why does a car like the Tesla still have old-style fuses?”
#52Because cars are not expected, under normal circumstances, to experience abnormal amounts of current on any given circuit. Unlike a house, where you can easily plug in something into the outlet that can overwhelm the circuit, in a car each circuit is designed specifically for a given maximum load. When you blow a circuit in a house, you have most likely massed up and plugged too many things into one outlet, or your d…
> These components are not expected to fail, even though they often do. Don't believe me, talk to any mechanic. However, because they are not expected to fail, they are often installed deep inside the car. So, now, if your headlight module fails, it costs $400 in parts, and several hours of labor to fix the same problem. Progress? Hell, when the HEADLIGHT BULB fails, which is something that IS expected to happen, it…
The issue is the engine compartments for a lot of vehicles are arranged by subcontracted firms. I know a guy who works for a company that does this for Ford, GM and Dodge, and there's not a mechanically inclined person in the bunch.
They're playing jigsaw with an engine compartment trying to get all the parts in in the most compact, but still workable, way possible.
It's sad when you think about it, because not only does it squeeze a lot of at-home maintenance out, which used to keep vehicles affordable, but now almost everyone discussing new vehicles discusses the maintenance costs.
Honestly, I'm not surprised the domestic car market essentially failed, because they're $40,000 printers. No one gives a crap about the up front price anymore, because they know they're getting screwed on the after-expenses so everyone's looking up how much their yearly maintenance expenses are going to be to make sure they don't end up paying more than the vehicle in a decade.
Re: “Why does a car like the Tesla still have old-style fuses?”
#53I'd worry about this if I had a fuse blow in my car in the last 10 years.
Re: “Why does a car like the Tesla still have old-style fuses?”
#54Because cars are not expected, under normal circumstances, to experience abnormal amounts of current on any given circuit. Unlike a house, where you can easily plug in something into the outlet that can overwhelm the circuit, in a car each circuit is designed specifically for a given maximum load. When you blow a circuit in a house, you have most likely massed up and plugged too many things into one outlet, or your d…
> This relay was expected to fail at some point (though they very rarely actually did fail)
> These components are not expected to fail, even though they often do.
I think this is wrong. If you look at QA statistics, you will find that parts are getting _more_ reliable. The old relays were expected to fail becuase they _did_ fail. The new modules are not expected to fail, and this is indeed the case. They fail much less often, and of course this means that in the occasional cases where failure occurs, it will be difficult to replace or repair.
Overall reliability is increasing and to say otherwise would seem to be a glib misstatement or misunderstanding.
Re: “Why does a car like the Tesla still have old-style fuses?”
#55Earlier quoted context omitted.
> These components are not expected to fail, even though they often do. Don't believe me, talk to any mechanic. However, because they are not expected to fail, they are often installed deep inside the car. So, now, if your headlight module fails, it costs $400 in parts, and several hours of labor to fix the same problem. Progress? Hell, when the HEADLIGHT BULB fails, which is something that IS expected to happen, it…
The issue is the engine compartments for a lot of vehicles are arranged by subcontracted firms. I know a guy who works for a company that does this for Ford, GM and Dodge, and there's not a mechanically inclined person in the bunch. They're playing jigsaw with an engine compartment trying to get all the parts in in the most compact, but still workable, way possible. It's sad when you think about it, because not only…
I worked in an auto shop a while back. One surprise is that a substantial part of a mechanics' toolkit is devoted to turning bolts and screws in hard-to-reach places. It's almost like a racket or something - auto companies put critical bolts in weird places, tool companies build tools to turn them anyways.
Re: “Why does a car like the Tesla still have old-style fuses?”
#56He's talking about fuses for the low-current auxiliary circuits. From the title, I thought he was talking about fuses in the battery and propulsion system. Fuses very rarely blow for random reasons today. There's been some progress since the "Lucas, Prince of Darkness" era.
The high-power system uses fuses because, if things overload there, you want power disconnected reliably and you want it to stay off. Lithium batteries do not handle overloads well. Not at all.
Re: “Why does a car like the Tesla still have old-style fuses?”
#57Because cars are not expected, under normal circumstances, to experience abnormal amounts of current on any given circuit. Unlike a house, where you can easily plug in something into the outlet that can overwhelm the circuit, in a car each circuit is designed specifically for a given maximum load. When you blow a circuit in a house, you have most likely massed up and plugged too many things into one outlet, or your d…
> These components are not expected to fail, even though they often do. Don't believe me, talk to any mechanic. However, because they are not expected to fail, they are often installed deep inside the car. So, now, if your headlight module fails, it costs $400 in parts, and several hours of labor to fix the same problem. Progress? Hell, when the HEADLIGHT BULB fails, which is something that IS expected to happen, it…
Yea, I like progress, but I don't like progress that hasen't
been thought through to the point of, "What will happen when
the component fails? Will the Technician be able to fix the
failed component--in a reasonable amount of time?". I see too many items being throw away because it makes no financial
sense to fix. I feel, as consumers, we need to ask for, and buy products that are able to be repaired. I know most people don't care, but some of us like to fix our cars, appliances, electronics, etc.. I don't blame it all on manufactures though. I remember
when I went to automotive school in the ninties. Saturn made
a conscious effort to make a vehicle that mechanics could easily work on, but no one seemed to care. Yes, Saturn was plaged by other problems, but I did appreciate the fact that
the engineers at least tried to build something--knowing that
components will need to be replaced, or fixed. For years, I
see this trend towards more gadgets(components that will fail) added to every consumer product, and every year these
products become harder to fix? I cringe when I see an automobile loaded with extra stuff that can break. I don't
think there's a mechanic out there that doesn't breath a little sigh of relief when a customer comes in with an older
simple automobile? The average person out there asks me why I keep that older
Toyota p.o.s. as a spare car. Mechanics never question why I keep my p.o.s..
Re: “Why does a car like the Tesla still have old-style fuses?”
#58The short answer is cost and that fuses are perfectly sufficient. Blade fuses are 100 for a dollar. PTCs are a handful for a dollar. Infineon ProFETs are a couple dollars per. When's the last time you blew a fuse on your car? For most of us, it's never. For those of us who have, there was almost certainly an electrical fault that was the root cause.
When a panel fuse on a car has actually gone out, it's an indication that Something's Gone Terribly Wrong and simply pushing a button on a popup isn't the right move. Tow it to the shop.
I say "actually" because I presume it's possible to have a false failure now and again - there may be a nonzero number of times in which the fuse just pops, that fuses just wear out.
Re: “Why does a car like the Tesla still have old-style fuses?”
#59This is a perfect example of the KISS principle. Since I would never presume to call Woz stupid, let's call it the KISW (Keep It Simple Woz) principle in this case. Woz is proposing that Tesla take well proven, very reliable, simple, inexpensive fuses that are very rarely even seen by customers and replace them with complex integrated circuits and software that will need a lot of testing, almost certainly be more exp…
Agreed. However, adding a single CAN bus ADC to the fuse PCB (to sense no voltage on circuits with a blown fuse) would cost almost nothing, and would allow the computer to provide information on the blown fuse and instructions on how to replace it. IMHO, breakers = expensive needless feature creep, but user feedback = welcome to 2015. EDIT: I was thinking of the 12V accessory fuses. In light of the reply from Tesla,…
yep getting a shock from the battery pack from a tesla is going to be bad news if not fatal.
That is one of the downsides of ev's whist an electric shock from mains is unpleasant its unlikely to be fatal higher voltage and amperage shocks are very nasty.
Re: “Why does a car like the Tesla still have old-style fuses?”
#60Well, even planes use CB today instead of fuses (and remote CBs on top of that, meaning they can be turned on/off electronically) I think WOZ is suggesting an active current control that, while doable, is probably too risky (and you really don't want to blow the expensive parts)
> Well, even planes use CB today instead of fuses (and remote CBs on top of that, meaning they can be turned on/off electronically) If you have something drawing too much current in a plane, and so it is a fire risk, it still might be overall safer to continue to use it. For instance, if it is something involved in lowering the landing gear you might decide it is safer to risk a small fire in order to get the gear do…
Also you have trained personal and emergency plans on board of a plan in contrast to your average street car