6n2 drivers side window only works from outside

Hi all,

2000 6n2 drivers side window doesn't operate from the inside switch.

For info, the window mechanism still works by use of the key on the outside, i.e. goes up and down if I turn the key long enough.

I've switched the connection by removing the door cover and confirmed that the switch isn't the issue as I can operate the passenger side with the "wrong" switch.

So question I have, is this a wire connection issue? If so with a multimeter where/what wires should I be measuring?

Thanks