LaCrosse Power Steering Assist Adjustable?

Hi,

Can anyone tell me if the steering assist on an '05 LaCrosse CXS can be adjusted or not. Mine has too much resistance and I am very aware of having to put more effort into small steering adjustments than I am used to.

I understand the steering assist is controlled by the computer, so I was wondering and hoping I could have the assist increased slightly to lessen the resistance at the wheel.

Thanks.

Rob