system is engaging and it gives the sound of a bad brake booster..

and the brakes to engage without me stepping on brakes.

When the rear streering is engaged electricly, it goes into gear but a light comes on that says;"Service".
The steering works for that one time and then disconnects
or goes out of gear and back to two wheel streering.
How do I service or take care of this problem myself?

I can't lock, or unlock vehicle with remote. The panic button on remote does nothing either. I changed batteries in both remotes, nether one works. Also,the power window, and door locks on passenger side are in-operative. I have checked what seemed to be ten thousand fuses, in three different locations, all are good, so where do I go from here? Please Help!!!!!!!