That trunk sensor is most often the trouble.

My car has 98000 miles on it, and I raise and lower the top more than anyone, I live in GA and have the top down many times each month, year around. The hydraulic system itself appears to be robust and well made - I truly believe that raising and lowering the top a lot does not "wear out the system" but instead, exercising it keeps it healthy. The few people who have come here with hydralic problems *SEEM* to be those with low miles and a car that is (perhaps?) "over-babied".

Not that babying a car is not my way - my car gets oil changes every 5000 miles, fleece filters, 100% pure gas (when I can get it) - it gets a lot of attention. It's just that I believe exercising mechanical systems is an effective and legitimate maintenance technique.