Weirdness after replacing window regulators..

[will x5]

Hi,

I just replaced the 2 front window regulators, and a rear one on my 2001 E53.. ... while out of the car i checked the old motors worked the new regulators up and down , by simply running +ve and -ve wires from a handy battery to the motor and then reversed them... the motors spun and the slides moved up and down... Installed everything back in the doors... the rear window goes up and down perfectly... the front driver window only goes down, and the front passenger window only goes up... no reverse movement ....

anyone ever hit this issue before? I am a bit stumped at how to proceed...
Would my testing of the motors that way affected them? ( cant see why as they were were working perfectly wgen testing ) ...any suggestions greatly welcomed..
cheers