2005 Chevrolet Trailblazer Steering problem

Just given you the whole story. Went to the truck and battery was dead. Hum started ok and but by the next day battery was dead again. I replaced the battery. The next day while turning the truck lost power steering but the truck was still running. Shut the truck off and restarted power steering came back. I decided to replace the power steering pump due to a lot play in the shaft. Also for maintenance I replaced the belt idler and tensioner.(Also the truck has a new rack and pinion about 6 months old in it.) The next day was driving and same thing happened again. List power steering during a turn but the truck stayed running. Checked everything fluid hoses and pump. All ok. Last time it list power steering I couldn't get it back for a while. While this may be just coincidence, I disconnected the batter for a minute and rehooked it back up then power steering came back. On all occasions the truck was only driven short distances. I'm at a total loss right now on it.