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Comment by jperras | Hacker News Reader

While disappointing and costly for Tesla, thankfully a power steering failure isn't typically a big deal, safety-wise.

If you've never driven a vehicle without power steering: it's marginally harder to turn the wheel, which really only affects you in parking lots and making turns from a dead stop (as is mentioned in the article).

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Try driving a car designed for power steering with a failed pump. It's much, much, much harder than a car that was designed from the beginning to be used without power assist. Moving or not it's a hand-over-hand struggle to turn the wheel.

It’s not “you’re going to die now” harder.

More like “this isn’t comfortable, better pull over and see what’s wrong” harder.

Depends on what is going on around you when it happens, how long it takes you to realize that something is wrong, and what to do about it. It wouldn't surprise me if many people would not even realize that they have power assist in the first place, and just assume that the wheel somehow got stuck and there is nothing they can do.

Although I would imagine that the most common failure case is the wheel slowly getting harder to turn over a period of days or weeks.

For a strong guy yes, no problem, for a much lighter or weaker person it can be a huge problem. Tesla is a heavy car, it would require some serious muscle to initiate a slow turn without powersteering.

It probably depends also on the car. I drove a friend's little Datsun pickup for a while with a failed pump, and while it was drivable, you did have to get used to using both hands to turn the wheel, especially at low speeds when you had to turn a little sideways and use and overhand grip to wrench the wheel around. Good times!

Some cars probably have more built-in leverage. A sports car may be the worst since it will have a pretty low ratio to begin with. My Camaro might not really be drivable because it has a low ratio rack as well as 285's on the front which are going to be a great big PITA to move.

If you're driving a vehicle with purely drive-by-wire controls and no mechanical linkage, you're going to crash. As far as I know the industry hasn't really deployed that yet, but it's on the way (conceptually at least).

I'm driving my VW Fox from 2005 with a broken pump for 12+ months now.

The only bad thing is parking, you get used to it. Gotta take the jacket off before attempting to park in or park out, or you are going to sweat a lot.

I had power steering disable itself randomly in a 2005 VW Polo. The required steering forces below 40km/h were suddenly extremely large. It was about 5 to 10 times the force that I remember from a heavier and larger car without any power steering that I have driven prior.

I guess you are lucky that your steerimg system is designed to fail more gracefully.

A Fox on tiny tyres is not the same as a 2 ton Tesla on wide tyres, where steering force required is concerned.

My power steering once failed when the accu died with (almost) all the electronics in the middle of the turn. With all the adrenaline in the blood, you won't have much problems controlling your car then ;)

You are right, it's quite a different experience comparing to cars from a few decades back.

> Try driving a car designed for power steering with a failed pump

I do this fairly regularly - I race an early 90s Honda Civic in a wheel-to-wheel series where the power steering pump has been closed-looped on purpose (weight savings, one less thing to fail during an 8-24 hour endurance race, etc.)

One has to remember that cars that were designed to be without power steering usually has 5 turns of the wheel from one side to the other, while cars with power steering only has 3, again usually. So a car that was designed to have power steering and looses it, is not really comparable to cars designed to be without one, and is a real pain to drive, especially in the city.

I have also been told that the steering column for power steering is not as strong because the design loads are lower.

It doesn't matter whether it is a servo or a human that turns the shaft, the design loads are a function of the weight of the car and the front/rear weight distribution as well as of whether or not the front wheels are driven or idlers.

You might be confusing a few things - older steering columns were very rigid (and thus "strong"), but were also a fairly major concern in frontal or rear collisions: they would essentially impale the driver if hit at the right angle.

Modern steering columns have a telescoping construction that allows them to collapse in the event of an impact so that this isn't a big of a concern.

Wont affect Tesla. Supplier is footing the bill.

Also, I expect most owners will wait until 1h fix (presumably much cheaper for all parties) is available.

As with nearly all recalls, it will most likely affect their stock price in the short term.

It's a bigger issue on an ICE car where leaking power steering fluid can leak or spray onto hot engine components.

A sudden loss of power steering can be very dangerous. Imagine you are on the inside left turning lane, an unexpected power steering failure could cause you to drive into the vehicle turning on the outside lane because your turning radius is now far wider.

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