2003 Dodge Caravan Power Steering

When it rains hard, the power steering fails, the alternator light comes on, and the defroster won’t work. When the rain lightens up, I hear a belt screeching, and then then the power steering will come back on. Mechanics have replaced the steering rack, steering pump, and belt tensioner, but none of these has fixed the problem. This problem happens when I’m parked and when driving. Any suggestions?

Is the splash shield in place under the engine?