So, I've had this car for a year and a half. The only issue with it was the headliner was drooping. A common issue. I took it into the dealer and replaced the headliner. A very hefty expense. It was in the winter and the roof seemed to work fine.

As soon as it got warm out the roof would open and seemingly go all the way down, but it would not lock. In the mornings, after the night, and it is cool out it seems to work. Once it warms up outside it does not. It always locks in the up position.

Maybe the headliner and the weather are all red herrings - I can only report that it usually does not lock and sometimes does.

Any ideas of what it could be? I tried to take out some hydraulic fluid because I saw on Top Hydraulics Youtube that it should be near the min line when it was up and it was at the max line. Doesn't seem to change much.

Maybe it is a sensor? Does anyone know what sensor tells the rooftop to lock once it is all the way down?

Any other ideas?