I know it's and older thread but maybe somebody will see this. I have the same problem where only the hatch functions. I have a second mdx, parts car now. I made sure all lock actuators worked before I pulled them, went to install the first one on the driver's door, it works, intermittently. Like if I pull the fuse and put it back in, it works immediately, once, then won't work again for a while. I checked both fuses and replaced them just in case but it hasn't changed anything. Obviously it's getting power? Not sure what to look for next.