Looking for help with this on my saf.

Basically just stopped working one day, light on button doesnt light up as it should and it doesnt de mist screen.

Have removed the button to check that out.

Can anyone help with resistances etc.

Im going across pin 1 and 2 and they are open circuit, when the button is pressed you get continuity across them but the second you take your finger off the button it goes open circuit again.

Anyone any ideas on how to propery test the switch or the multiplug on the car?

cheers