I removed the centre door roller assembly to replace one of the rollers.I had great difficulty getting enough slack in the cables to remove the assembly but got it done . I replaced the roller , put all back together and tried the door manually, it worked great . Tried it with power and when it was about 3 in. from closed it reversed. I closed it manually then hit open, it was trying to open without unlatching , I pulled on the handle to release the latch , it went to open but came to a very hard stop. I pulled the fuses , opened and closed it manually, reinstalled the fuses, same problem. I don't know if I threw something out trying to get some slack in the cables or what . HELP..