Annunciators

Question 1

PSEU

Answer 1

Fault detected in PSEU, or

Overwing exit flight lock fails to disengage

Inhibited in flight

Extinguishes with parking brake set or both engines shutdown

Question 2

ON DC (IRS)

Answer 2

Respective IRS is operating on DC power

Right ADIRU disconnects after 5 min

Activates ground crew call horn on the ground

Question 3

DC FAIL (IRS)

Answer 3

Respective IRS has lost it’s backup DC power

(If both illuminated, battery almost dead)

Question 4

FAULT (IRS)

Answer 4

Fault in respective IRS NAV or ATT mode

Question 5

ALIGN (IRS)

Answer 5

Steady - respective IRU in align mode

Flashing
-Movement during alignment, or
-No position entered, or
-Significant difference between old and new position

Question 6

ENGINE CONTROL

Answer 6

Non-dispatchable engine fault

Inhibited in flight, must be on ground with engine running

Question 7

REVERSER

Answer 7

Thrust reverser is commanded to stow

Extinguishes after 10 seconds when reverse is fully stowed and isolation valve is closed

If illuminated for > 12 seconds, malfunction in reverser system has occured

Question 8

PASS OXY ON

Answer 8

Passenger Oxygen Masks activated manually or automatically

Question 9

LOW QUANTITY (Standby HYD)

Answer 9

Illuminates when standby hydraulic quantity reservoir is less than 50%

Always armed

Standby system leak empties reservoir and reduces system B to approx 72%

Question 10

LOW PRESSURE (Standby HYD)

Answer 10

Low output pressure of electric standby hydraulic pump

Armed when
-Standby hydraulic pump selected on
—Either FLT CONTROL switch to STBY RUD, or
—ALTERNATE FLAPS to ARM

-Force Fight Monitor, or

-Automatically
—FLT CONTROL A or B is ON (normal), and
—Low pressure in A or B, and
—Airborne flaps extended, OR
—On the ground > 60kts

Question 11

STBY RUD ON (Standby HYD)

Answer 11

Standby hydraulic system is activated

-Manually via FLT CONTROL A or B to STBY RUD, or

-Force Fight Monitor

-Automatically
—FLT CONTROL A or B on, and
—Low pressure in A or B, and
—Airborne flaps extended, OR
—On the ground > 60kts

Question 12

LOW PRESSURE
(HYD Panel below FLT CONTROL switches)

Answer 12

Low hydraulic pressure to respective flight control actuators

<1,300 PSI

Question 13

FEEL DIFF PRESS

Answer 13

Excessive differential pressure in elevator feel computer

Can be caused by:
-Loss of HYD system A or B, or
-Elevator PITOT blocked/failed, or
-Activation of Elevator Feel Shift Module

Question 14

SPEED TRIM FAIL

Answer 14

Failure of a channel or Speed Trim System [or MCAS function (MAX)]

Dual channel system

Question 14

MACH TRIM FAIL

Answer 14

Failure of a channel or Mach Trim System

Dual channel system

Question 15

AUTO SLAT FAIL

Answer 15

On recall, failure of a single Stall Management Yaw Damper Computer (SMYD)

Otherwise, indicates failure of the Auto Slat system

Dual channel system

Question 16

YAW DAMPER

Answer 16

Yaw Damper is not engaged or inoperative

Yaw Damper requires:
-HYD System B
-B FLT CONTROL switch ON
-SMYD computers

Loss of system B renders the Yaw Damper inoperative, HOWEVER the YAW DAMPER caution light will NOT illuminate