250407 black screen

Hi

I have 250407 giving me Black Screen. RED Power Light on. Fuse and Power Supply Good.
VR2 no 5V Output and No Input. Vr1 oV Input and 0v Output.
CN2 10 and 11 NO 9VAC.
C49 5V. IC's give 5V.
Checked:

1)Power Switcn (SW1) OK
2)L4 and L5 L2 OK
3)CR4 Bridge Recitifer OK

Again no Input at Vr1 and Vr2 and No Output at Vr1 and Vr2

help

Gerritt it was the Switch, no contact at 9VAC..thank you Gerritt!

took switch from Working Motherboard and then it worked. I cleaned the non-working with sand paper and working now also