fuel flap wont open

[churp]

hi, my fuel flap wont open with the switch,

have plugged in vcds and can get it to open via activations, checked the switch output and it not recognising that the button is being pressed. there are no fault codes and rest of stuff all work on door assy.

Address 42: Door Elect, Driver Labels:. 1K0-959-701-MIN3.clb
Part No SW: 1T0 959 701 D HW: 1T0 959 701 D
Component: Tuer-SG 006 1202
Coding: 0000757
Shop #: WSC 06784 678 06784
VCID: 387F1DFF4B94B58A2D-806C
No fault code found.

there are 3 wires fitted to the switch, a purple, a yellow/grey and a brown wire. if you earth out the purple wire, the flap opens. have continuity on all 3 wires between the switch and the multiplug where it meets the module on the door connected to the window motor.
ideas welcomed

[Crasher]

So you can see in the drivers door electrics measuring blocks that the controller is not seeing the button being pressed? The switch works by taking an earth at pin 1 (brown) and sendingh is down to the door controller from pin 4 (liac) so if you check the brown of continuity to earth and if it is OK, jump the brown to the lica, if that woks than the switch is faulty, it is called E319. If the earth supply was faulty I would think the mirrors would not work and I can't imagine a wiring fault between the switch and the controller.

[churp]

hi, thanks for your help, early indications are that the issue lies within the switch, as sometimes I get continuity between the two pins and at others I don't get any, obviously would only get it when button used. intermittent faults are the best lol.
Crasher always a big help as usual. thanks. I endeavour to have this fixed before I need to refuel again, well thats the plan.... but I have a trusty wire just in case lol

[Crasher]

I hate intermittent faults, "if you are going to go wrong, stay broken for God's sake!"

[churp]

fingers crossed that its fixed. replaced switch and have tried a dozen times and it working as it should.