Yellow pressure question

[Capt. Pip]

Hi,

Doing my yellow pressure test with the DC on it shows pressure on captain side. Every time I am about to take off for some reason the yellow pressure is 0. It also prevents me from extending gear on landing. Am I forgetting something?

Pip

[Huibrecht]

ENG 2 - 3 pumps ON (all flight)
PTU pump ON and AC pump AUTO during approach

[Capt. Pip]

They are but still 0 pressure

[Capt. Pip]

I mean, should there be yellow brake pressure during flight (> 0)?

[smashingjonor]

You only get brake pressure when you activate the brakes, which means that they indicate 0 in the air because you are not using them.

The brake system is not connected to the landing gear retraction/extension mechanism so seeing 0 brake pressure doesn't mean anything for the landing gear extension/retraction, unless you have 0 hydraulic pressure on the hydraulics panel on the overhead.