Funny mirror issues!

I have just replaced my drivers 10 pin wire mirror, but the one i have put on goes up when instead of down in reverse and does not return to its original position, so after a few reverses it ends up looking into space!
any ideas on this one!!??

Disconnect the ten pin plug and either you or your pàssenger stick your hand out of the window to adjust it?

Sounds like your replacement is duff. I keep hoping someone will produce an article on how to fix these, but I'm beginning to suspect that it's more hassle than they're worth. I think the problem is related to the microswitches used for positioning the motors getting worn. My passenger mirror operates in reverse too now.