737 MAX Flight Crew Operations Manual
Normal Procedures -
Amplified Procedures
MN-FLT-OH-201
NP.21.13
SPKR switch - ON
TEST/RESET switch - Push and hold
EMERGENCY/Test Selector (as installed) - Push and hold
Advise any maintenance personnel using the FLT Interphone
that a test will be done on this communication channel.
Simultaneously push the Push-to-Talk switch, the
EMERGENCY/Test selector (if installed) and the
RESET/TEST switch.
Verify oxygen flow sound is heard thought the flight deck
speaker.
Push-to-Talk switch - Release
TEST/RESET switch - Release
Mask/Boom switch - BOOM
EMERGENCY/TEST selector - Push and hold
If applicable: Regulator selector - Rotate to EMER
Continue to hold the TEST/RESET switch down and push the
EMERGENCY/TEST (if applicable) selector for 5 seconds.
Verify that the yellow cross shows continuously in the flow
indicator.
Verify that the crew oxygen pressure does not decrease more
than 100 psi.
If the oxygen cylinder valve is not in the full open position,
pressure can:
Decrease rapidly, decrease more than 100 psi or increase
slowly back to normal.
Release the TEST/RESET switch and the EMERGENCY/TEST
selector (if applicable). Verify that the yellow cross does not show
in the flow indicator.
Regulator selector (as installed) - Rotate to 100%
Normal/100% selector - 100%
Crew oxygen pressure - Check
Clock ............................................................................................. Set
TIME/DATE pushbutton .............................................. UTC time
-700 and -800 Fleets Only
NOSE WHEEL STEERING switch .............................. Guard closed
March 1, 2021
