The fluid reservoir is on the driver's side toward the back of the trunk. You need to take off the liner and see if it's full. It's clear plastic so you can spot it easily. If it's full it's the pump, if it's not there's a leak some where. Of course it could be the seals around the piston itself. Had that happen to me on my old Lebaron convertible. That was back in 2005 and it was $700 to fix it then.