Power steering light

06 Sport, 70K miles. I got a power steering light and power steering was dead. Cycled ignition off and on but didn't help. I disconnected the battery 5 minutes didn't help. Took it to the dealer. Maintenance "coordinator" saw the problem. They called back later and said the problem had dissappeared by the time the techs got to it. Been fine for 3 weeks now. Anyone with any experience with this?

As a reminder, this is an all electronic system - no fluid.