I found this thread in google on 2.25.08, so since its being added to google 3 years later after the post, then I want to add this... Yes, volscot who posted above, is absolutely correct. I have a 96 Mercury Sable having the same problems... No Power steering in Reverse and occasionally in forward gears.
I removed the Radio Mute fuse (far right, next to bottom row). Its a 5amp fuse, btw. After removing it, there has been no more problems. Now my power steering works in reverse. Since removing that fuse my Windshield wipers, Power Locks, Power Steering has not intermitently cut off like it always has been the past 2 months after driving about 15-20 mins.
Yes, the post here (or another site I forgot) reveals that anyone can fix this problem. After about 1997-1998 Ford started changing the name of the part from a Neutral Safety switch a Transmission Range sensor. So when you search Autozone.com or Advanced Auto parts websites, it doesn't return any results and makes it seem that you have to go to Ford dealership which is not true. Instead of searching the correct term of Transmission Range Sensor, instead search Neutral Safety Switch. The part is 25.99 at
Autozonep. They have an OEM version that needs ordering for 77.99 but haha, disregard.
Now heres the
repair instructions. Now that you know what the pictures look like, then look below your brake resevoir flud container. You'll see this part. It has a cable/linkage thingy in the middle of it and a connector at the end. Its easy to get to from the top of the engine and it is only two bolts holding it down... A 2nd grade student could replace this...

But when you locate it, then just read the instructions at the link above.
But until you get around to replacing this part, stop all of your power steering failures and power window/lock, radio, windshield wiper and RR defroster from failing intermitenly by doing this:
Remove the fuse called Radio Mute (far right, next to bottom slot) - Its even labled in the fuse cover. Its a 5 amp fuse. Remove it and all your problems will go away, trust me