Steering by wire ???

[DWncchs]

Are the late model cars "steering by wire" ? I didn't know until recently the throttle was "by wire" and it looks as if some of the hybrids are "braking by wire" (which scares me) but STEERING ?
My Saturn has electric assist steering and I get that but the owners of new Corolla's are reporting the car wanders on the highway,that sounds as if there is no shaft connection between the steering wheel and the front wheels.

[big_G]

Sure would keep the lawyers busy....imagine the wrecks when someones car loses a battery/alternator going down the road? I doubt a car company would be so stupid. Wait...maybe Toyota would do it.

[mrvette]

Look, in jobs past I have been shoved around plenty by EMI/RFI, and there simply is NO group of tests devised by man or beast or computer that can replicate 5 million cars on the road with all the possible variations in this EMI/RFI enviornment...period....

that and plain AGE and grounds, rust, wiring, connections, assy techniques, plating on interconnects, you get the rong set of shit going on and the very best laid plans go in smoke.....

I would never have a car where the basic mechanical functions are done through computers....even the mighty Boeing had a tail rudder malfunction....

and they are some of the best engineering groups in the whole damn world....

I don't even care for ABS, tell the truth....

[clutchdust]

I've been asking for weeks now why the hell we have to have electric gas pedals anyway. It's stupid. But of course the answer is the environazis/politicians mandated unnecessary laws all in the name of CAFE and "saving the planet".

[69427]

Originally Posted by clutchdust

I've been asking for weeks now why the hell we have to have electric gas pedals anyway. It's stupid. But of course the answer is the environazis/politicians mandated unnecessary laws all in the name of CAFE and "saving the planet".

Couple reasons. The first is a reduction in emissions due to the ECM being able to coordinate the fuel flow changes with the throttle changes. (The ECM no longer has to play catchup with the injector pulses every time the driver nails the throttle or lets up on the throttle.) Pretty much just an effort to deal with EPA regulations. The second reason is a reduction in vehicle weight and parts count. Several functions can be combined into one. The throttle body can do its normal function, along with replacing the cruise control hardware, and also any C4-like ASR/traction control hardware that might be used in the vehicle.

[69427]

Originally Posted by DWncchs

Are the late model cars "steering by wire" ? I didn't know until recently the throttle was "by wire" and it looks as if some of the hybrids are "braking by wire" (which scares me) but STEERING ?
My Saturn has electric assist steering and I get that but the owners of new Corolla's are reporting the car wanders on the highway,that sounds as if there is no shaft connection between the steering wheel and the front wheels.

I'm not aware of any production vehicles being steer by wire. (Please correct me if there are any.) There are a few that have electric power assist, as you are familiar with, but the mechanical connections are still the same as previous steering setups (steering column, u-joints, and a R&P box). While it's certainly possible to make a steer by wire vehicle, it's what we used to call "lawyer bait". It's an item that's just too easy to be used by an ambulance chaser to sue you, even if the vehicle was not at fault.

[TimAT]

Originally Posted by mrvette

I would never have a car where the basic mechanical functions are done through computers....even the mighty Boeing had a tail rudder malfunction....

and they are some of the best engineering groups in the whole damn world....

I don't even care for ABS, tell the truth....

Yep they did. But it was a mechanical (worked by air pressure) limiter that failed- no electrickery involved. Other than the servos that shut off hydraulic pressure- and that was a pretty basic switch- once a specified air speed was reached it clicked off the servos to limit rudder travel.

[mrvette]

Originally Posted by 69427

Couple reasons. The first is a reduction in emissions due to the ECM being able to coordinate the fuel flow changes with the throttle changes. (The ECM no longer has to play catchup with the injector pulses every time the driver nails the throttle or lets up on the throttle.) Pretty much just an effort to deal with EPA regulations. The second reason is a reduction in vehicle weight and parts count. Several functions can be combined into one. The throttle body can do its normal function, along with replacing the cruise control hardware, and also any C4-like ASR/traction control hardware that might be used in the vehicle.

I dunno man at 600 rpm the sparks are 40 per second...at 6000 it would be 400/second....400 hertz, a computer clock runs a minimum of what?? 2 Megs?? it's gone around the corner fell asleep got up had coffee before the next injector needs fire...

I dunno, servo motor is a servo motor, so the cruise is now on the throttle body directly....maybe I give it 1/2 a lbs saved....got more dirt on a car a week old, then that.....

As for ASR/traction control, I dunno, I have to ask why bother?? I been driving 50 years without it....course I don't have phone text either....

[DWncchs]

Originally Posted by 69427

I'm not aware of any production vehicles being steer by wire. (Please correct me if there are any.)

I don't actually know of any,my thread was prompted by many news reports stating that the electronic steering on new Corollas have the drivers reporting the car just weaves back and forth on the highway and turning the steering wheel does nothing. That "sounds" like there is not a shaft connecting the wheels and steering wheel.

The other thing I heard was about the Prius brakes and that they switch over from "the hydraulic brakes" with a momentary LOSS of braking. Switch over from what ? to what ? I'm "assuming" some of the braking is part of using braking energy to recharge the battery's.

I've done a little bit of Google research on these but really haven't had much time to devote and was hoping you guys might have the answers.

[clutchdust]

Originally Posted by 69427

Couple reasons. The first is a reduction in emissions due to the ECM being able to coordinate the fuel flow changes with the throttle changes. (The ECM no longer has to play catchup with the injector pulses every time the driver nails the throttle or lets up on the throttle.) Pretty much just an effort to deal with EPA regulations. The second reason is a reduction in vehicle weight and parts count. Several functions can be combined into one. The throttle body can do its normal function, along with replacing the cruise control hardware, and also any C4-like ASR/traction control hardware that might be used in the vehicle.

Yep, that's pretty much the exact reason I said. What I don't buy is the reduction of weight. You ever see what a race team pulls out of a production car to prepare it for track duty, and there's at least a couple pounds (sarcasm) of wires and computers and other unnecessary crap. I'd be really interested to see an ounce by ounce comparison between a mechanical pedal, cable and linkage vs. a servo pedal, wiring harness and servo inlet.