Front passenger seat gets stuck halfway back, what causes this? Can I fix mysel?

Hello, something is stopping that motor from moving -- usually it's a restriction, as you've supposed. But unfortunately, if you don't see anything, the seat will have to come off and inspection of the motor mechanism and track is needed. There's no other real answer - you just have to investigate and figure out what's causing it to happen. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops