Annunciator Panel

Question 1

Answer 1

Indicates the APU Master switch is ON and APU Generator power is available but is not powering any AC Bus. Normally the only amber annunciator light on for takeoff.

Question 2

Answer 2

Indicates the left Generator Bus is not powered

Question 3

Answer 3

Indicates the left generator relay is open

Question 4

Answer 4

Indicates the oil pressure in the left CSD is below a predetermined value

Question 5

Answer 5

Indicates the Emergency Evacuation lights are not ARMED and the aircraft is electrically powered. (Light will be OFF when switch is ARMED and Emergency DC Bus is powered)

Question 6

Answer 6

The AC crosstie relay has automatically locked open so that the system cannot crosstie a faulty bus and a good bus. It cannot be reset in flight. (Indicates a nuisance lockout if on by itself. One attempt can be made to reset on ground. NOTE: This light can illuminate with AC Bus Crosstie switch in AUTO or in OPEN)

Question 7

Answer 7

Indicates DC Transfer Bus is unpowered. Since Master Caution & Warning lights are powered by DC Transfer Bus, the Caution light should be OFF. (If the Master Caution light is ON, the annunciator light is “lying.” Then light indicates a failure of the Bus Sensing circuit, which can be verified by doing a Fire Warning test.)

Question 8

Answer 8

Indicates the right Generator Bus is not powered.

Question 9

Answer 9

Indicates the right generator relay is open.

Question 10

Answer 10

Indicates the oil pressure in the right CSD is below a predetermined value.

Question 11

Answer 11

Indicates one, or both, DC Buses are unpowered. Check DC load meters to verify the dead Bus or Buses. (If both DC load meters on the same side read zero, this could indicate a faulty AC Bus on that side of the electrical system)

Question 12

Answer 12

Pressure in the L or R hydraulic system is below approximately 1,000 psi. (The Hydraulic Low Pressure Light sensor is downstream of the Spoiler Bypass Valve. If the light is on but hydraulic pressure is normal, the Spoiler Bypass Valve may be OFF)

Question 13

Answer 13

The temperature of the hydraulic fluid in the L or R hydraulic reservoir is above acceptable limits & the L or R hydraulic system must be shut down.

Question 14

L/R FUEL HEAT ON

Answer 14

Indicates that the respective Fuel Heater Valve is not closed.

Question 15

IGN SYS A/B SELECT

Answer 15

Indicates that the Selector Switch is in the respective position. A is burner can #7 B is burner can #4

Question 16

L/R START VALVE OPEN

Answer 16

Indicates that the respective start valve is not closed.

Question 17

L/R OIL STRAINER CLOGGING

Answer 17

Indicates a pressure differential of 35 psid across respective oil filter. (OK to be on for up to 5 minutes if the oil is -25 C or colder)

Question 18

L/R LOW OIL PRESSURE

Answer 18

Indicates that respective engine oil pressure is 35 psi or less. (DC Transfer bus powered, indication of oil pressure during a battery start).

Question 19

L/R INLET FUEL PRESSURE LOW

Answer 19

Indicates that fuel supply pressure to the respective engine is below 5 psi.

Question 20

L/R FUEL FILTER PRESS DROP

Answer 20

Indicates that a pressure differential of 5 psid across the respective engine fuel filter. (If fuel is cold - 15 C this may indicate ice forming in the filter).

Question 21

L/R REVERSER ACCUMULATOR LOW

Answer 21

Indicates that pressure is below a specific value.