Re: 737 Pressurisation Q
Yup, ASFKAP you are right.
"Jurassic Classic" Dual Bleed Light illumination depends on valve position.
For it to illuminate either the APU bleed air valve and the number one engine bleed air valve have to be open, or, the APU bleed air valve, number two engine bleed air valve and the isolation valve need to be open.
Haul.