Ford Fiesta Steering Position Sensor power loss reset

I'm bench testing a Fiesta electric steering column for a retrofit into a mk1 Focus, and the testing is successful.

I can send it an rpm signal and a speed signal, and it will activate and vary power depend on the "vehicle speed".

I can also read the steering angle that it broadcasts, and I would really like to use that signal in my datalogging. The problem I face is that whenever power is shut off to it, the steering angle resets to zero.

This column has 2 power inputs, one constant on, and one switched. From my testing, I can see that as long as I leave the constant +12v connected, it will remember its last position AND track position changes while the switched +12v is off.

My car is a race car, with a small race battery. So I intend to shut this off completely so there are no parasitic drains on the battery. That means I will have to remember to center the steering before I power it on every time, otherwise my steering signal will be wrong.

Question is: How does the OEM deal with this? The way I see it, in an OEM car anytime the battery is disconnected or completely drained, the ecu will lose its correct steering position. They must have some solution I'm not aware of.

So is there any way I can correct or account for this? While avoiding parasitic drain, and without having to always remember to center the wheel?

OH! And one secondary question:

The steering motor powers on when I send rpm > 0. However, it does NOT turn off when the rpm and vehicle speed goes back down to 0.

I would like to save the battery. So I'm looking for a way to shut the steering off via canbus when the motor stops.

Anyone have any tips on this? It's not a big deal, but the more I can do to save the battery the better.