Questions on Atwood water heater- troubleshooting

[willerjim]

Hello,

1982 280 motorhome

I am getting 12v to the controller

Switch in bathroom stays let red..... not lighting

4 wires on the controller

Power
switch goes to sensor on tanke
switch dotto
ground
ignitor

I AM GETTING 12 V INTO THE BOX. WHEN IT IS PWERED UP, I CAN HEAR A FAINT HIGHT PITCH NOISE AS THOUGH IT IS TRYING

HOW DO I KNOW IF IT IS A CONTROLLER- OVER $100- OR THE IGNITOR?

HOW MUCH VOLTAGE DOES THE SPARK PLUT TYPE WIRE PUT OUT?

THANKS

Also anyone tell me how to add pics to these posts? I click "attach" above and nothing

Jim in Denver