I discovered that my front roof locks were not reaching the ratchet depth and thus the motor stalled while still receiving power. I believe this is very bad for the motor. So I adjusted the receiver nuts to get them working properly. I made the adjusting tool as follows. I took a deep socket with the same outside diameter as the locknut, modified two jig saw blades to fit into the nut grooves and secured them to the socket with two gear clamps. I thought this information may be helpful.