Help?? Its dark and cold and the windows stuck!!

[rob hod]

        Sods Law, Its cold and dark and on the way home the rear left window
gets stuck part way down.

    Can anyone help with  a bit of diagnostics?

    The window will go further down but not back up.

    Both the console switches and door switches will move it down but not
up.

    Could it just be a fault with the door switch that is preventing the
console switch working in the up position?

    Does the motor get a reversed polarity supply to move it up?

    Any help much appreciated,  i'm off into the dark with a multimeter and
screwdriver set.







rob