How to repair 2002 xk8 convertable top motor that has no power to raise the top?

Have you checked the hydraulic fluid level? Usually this problem is related to a low fluid level. Take off the cover on the right side of the trunk. Above the CD changer you'll see the hydraulic pump. You can easily see the fluid level right on the side of the pump. If it's low, fill it up with Pentosin fluid, which you can get at most auto parts stores.