The spoiler lowering switch is located on the underside of the trunk lid being pointed at with the screwdriver in the image below.

To determine if this switch is your problem remove the brown wire connector and use a jumper wire, as shown in photo to simulate a closed circuit across the connector. See photo with jumper wire below. With jumper wire in place the BCM now sees a closed switch signal and believes the spoiler is in the lowered position and it is ok to lower the top. Turn on your car and unlatch the roof D ring. As you do this you should see the windows go down and top should work. If the window do not move you have some other problem. This sub minature switch is subject to a lot of contact wear because it is closed all the time you are driving and the spoiler is down. I purchased the switch from JAMECO but as others have pointed out there are additional sources.