737 MAX Flight Crew Operations Manual
Supplementary Procedures
Chapter SP
Fire Protection
Section 8
MN-FLT-OH-201
SP.8.1
8 Fire Protection
Fire Protection
File Highlight
Fire and Overheat System Test with an Inoperative Loop
YA201 - YT602
To determine the specific inoperative loop:
OVHT DET switches.................................................................. A
Test switch ................................................................ OVHT/FIRE
If the FAULT light stays extinguished and both ENG
OVERHEAT lights and engine fire switches illuminate, loop A
is good.
If the FAULT light illuminates and the ENG OVERHEAT light
and engine fire switch for an engine stay extinguished, there is a
fault in loop A of the detection system for that engine.
OVHT DET switches...................................................................B
Test switch ................................................................ OVHT/FIRE
If the FAULT light stays extinguished and both ENG
OVERHEAT lights and engine fire switches illuminate, loop B
is good.
If the FAULT light illuminates and the ENG OVERHEAT light
and engine fire switch for an engine extinguished, there is a fault
in loop B of the detection system for that engine.
OVHT DET switches...................................................As required
Select the good loop for each engine (NORMAL if both loops
tested good).
Test switch ................................................................ OVHT/FIRE
If the test is successful leave the fire panel in this configuration
for flight.
March 1, 2021