If the ignitor has the pilot on, but the gas valve does not open, shut it down. Let it cool off. Now, along side of the pilot you should have a flame sensor that is made of porcelain with a metal tip that sets in the pilot flame. Use some steel wool or fine sanding cloth and clean the metal tip of this sensor. If its dirty, it will not send a signal to the module or circuit board to fire the main gas valve. This should take care of this problem, unless it goes deeper. This is where you start.
Shastalaker7

Cleaned tip. Performed controller self test... passed. There's approx 3 ohms measured at all sensors. Cleaned dust from entire unit using compressed air. Still, no 24 volts measured @ gas valve electrical leads.