liudr:
retrolefty:
liudr:
I stand corrected. Here is what I found for one of the vehicles:Nissan chose an electrohydraulic power-steering setup in place of some of its competitors' fully electric systems, a best-of-both-worlds solution that provides the feel of a conventional hydraulic setup with the economy benefits of an electric rack. The decision pays dividends the second you start moving -- the steering communicates with the driver, loads up naturally, and suffers from minimal torque steer.
So yes the power steering is not going to work when power is out. I also suspect there is a program to translate the steering wheel turn into power on the electrohydraulic pump, and yes speed sensitive steering so a problem with that program may translate into spurious maneuvers. I was wrong thinking a motor moves the wheels. A pump does that.
But more fundementally does that means that a failure of the pump in the Nissan would still allow 'armstrong' direct mechanical steering control for the driver?
Lefty
I'm no mechanic but I doubt you can still turn because I think the pump is not mechanically attached to the wheel. The "other" cars mentioned in the internet blurb must be using electric motors instead of pumps to turn the wheel. That means you have to reach under your hood to spin that motor's rotor if you want to turn the wheels.
It doesn't sound like you have a good understanding on how even conventional power steering works. A pump's output can never be mechanically attached to anything as it's output is a fluid under pressure routed to something that can turn that fluid pressure back to a mechanical force. Standard power steering uses that method but still allows for manual steering even if the pump fails.
So still looking for a definitive answer with reference to any present consumer car uses true steer by wire only, where there is no driver manual (unassisted) steering available if primary power is lost?
Lefty