New owner of 1998 slk 230. The top worked fine for first two weeks while the weather was really hot. Yesterday morning the temp was 63 degrees attempted to retract the roof and the windows went down the trunk opened but the roof did not move. In the evening the temps returned to high 80s and the roof worked fine. This morning 62 degrees the roof did the same trunk opened but the roof never retracted. Could this be an indication of low hydraulic fluid? Thanks in advance.