Originally Posted by woode (Post 2143515)

Yes, I am positive in my case. I literally could not turn the steering wheel more than a few inches using all my strength. When the car is moving it is generally easier to turn without power steering at all.

Originally Posted by Ultramaroon (Post 2143531)

I looked for an actual copy of the TSB. Found the number but didn't have any more luck.

According to what I found the pump motor would overheat because it was fighting a filter clogged with rust. That does NOT fit with your experience. Did you ever find out what really happened?

Originally Posted by woode (Post 2143538)

No, it only happened that one time.. and I sold the car not long after so never had the TSB performed.

Originally Posted by woode (Post 2143515)

Yes, I am positive in my case. I literally could not turn the steering wheel more than a few inches using all my strength. When the car is moving it is generally easier to turn without power steering at all.

Originally Posted by Tomking (Post 2145016)

That is exactly what has happened to me, I put my full weigh on it and was only able to pull a few inches. Whether it was lost of power or locking issue, it is very series issue.

For those in doubt, I am in my 50's and have been driving lots of car without power steering in the early 80 so I would know what it feel like.

My "Steering locked" issue remained until I turn off the car and leave it for 10 secs before turning it on again. It was not cutting in and out like some mentioned here.

Originally Posted by Sarlacc (Post 2142204)

Anyone got any input on how electric power steering works in general, and on our cars in particular?

Originally Posted by Tomking (Post 2145016)

That is exactly what has happened to me, I put my full weigh on it and was only able to pull a few inches. Whether it was lost of power or locking issue, it is very series issue.

For those in doubt, I am in my 50's and have been driving lots of car without power steering in the early 80 so I would know what it feel like.

My "Steering locked" issue remained until I turn off the car and leave it for 10 secs before turning it on again. It was not cutting in and out like some mentioned here.

Originally Posted by Ultramaroon (Post 2145364)

This is the stuff that kills people.

Originally Posted by mav1178 (Post 2145406)

.. only if it's an actual lock issue.

If my steering was locked, I would not be able to turn it at all, let alone "a few inches".

-alex

Originally Posted by Ultramaroon (Post 2145421)

I am fully converted to OP's argument. He confused the issue with his defensive response about people not owning the car and how it's hard to turn when it's off but this sounds different.

Originally Posted by chaoskaze (Post 2141174)

Ur high school must be amazing, the stupidest thing I ever did was cramming 9 guys into 1 Corolla...

Originally Posted by Ultramaroon (Post 2139793)

...they don't stick on. They flop open.

Originally Posted by HunterGreene (Post 2145435)

And one last thing...Thanks for the new sig, Ultra ;)

Originally Posted by mav1178 (Post 2145433)

Then the question is:

with the car in the "On" position but engine not started, is the amount of force needed to turn the steering wheel the same as when the initial problem occured?

If so, it's not a lock issue.

If not, it's an isolated lock issue that is most likely related to a bad steering input sensor, motor, or both.

-alex

Originally Posted by HunterGreene (Post 2145435)

Frankly, I am surprised that the thread is still on-topic, given that both Tcoat and Ultramaroon have chimed in.


And one last thing...Thanks for the new sig, Ultra ;)

Originally Posted by mobybrz (Post 1060509)

Yes, there is a power steering ECU. It is connected to the CAN, the TRQ1 and TRQ2 steering sensors, and an angular resolver (angle sensor). It outputs to the power steering motor.

What you mention between the IS versions isn't (or at least is extremely likely to be) different ECUs. It is more likely different *maps* juts like we are all aware of with ECUTEK on the engine ECU. Theoretically, it should be possible to perform the same reverse engineering work on the power steering ECU to allow maps to be edited or adjusted. I wouldn't be surprised if there is a different EPS map between the FR-S and the BRZ given the differences in suspension.

As it stands, I would imagine the GT86/FR-S/BRZ steering maps based on mostly on speed and driver applied torque. There is might be/likely is an influence from the VSC mode settings, steering angle, gear, and measures of yaw angle (side slip/rotation, the same measure that drives VSC intervention).

To give an example, one could theoretically create a map that is designed to assist the driver i an accident avoidance manuever on the highway. The ECU could detect a likely avoidance maneuver and provide an increased steering torque initially (effecitvely increasing the drivers turning rate) before ramping down the provided torque (slowing the drivers turning rate) to prevent an overcorrection and help dampen any potential for a tank slapper. You could use (again theoretically) anything coming over the CAN to influence the map.