(2)
Applicability
(a)
Existing faults
(b)
Fault history
(c)
Ground test fault display
(3)
Fault message
(4)
Fault details
(a)
Detail 1 - message number
(b)
Detail 2 - flight deck effect
(c)
Detail 3 - most likely LRU(s) causing the fault
(d)
Detail 4
1) 4a - fault latched or not
2) 4b - hard or intermittent fault type
C. Before trouble shooting the yaw damper system, ensure hydraulic and electrical power is applied to the airplane and the rudder operates normally without the yaw damper system engaged. The flight control system B switch must be on to engage the yaw damper system. Ensure the yaw damper system, master caution, master dimming bus indicator lights, dim and test, autopilot engage interlock and warning light circuit breakers are closed before attempting to engage the yaw damper system. To prevent misleading indications, test operation of the autopilot disengage lights by pressing lenses to ensure bulbs illuminate. It should be noted that the yaw damper engage light is normally illuminated whenever the yaw damper system is not engaged. The air data computer does not have to be energized for self-test of the yaw damper system since no interlock voltages are provided to the yaw damper system. However, the air data computer must be installed since the yaw damper q-potentiometer is used in the system. Voltage thorough the q-potentiometer is provided by the yaw damper system. The yaw coupler BITE is calibrated with no airspeed inputs to the air data computer. Removal of black boxes and system components requires normal safety and maintenance precautions such removal of power prior to removal of components and capping of all exposed electrical connectors.
2. Yaw Damper BITE
A. BITE entry
(1)
Press ON/OFF on the YDC BITE panel. Observe the ENTER BITE? is displayed on the panel.
(2)
Within 10 seconds press YES. Observe that PLEASE WAIT is temporarily displayed followed by EXISTING FAULTS? on the YDC BITE panel. Observe the AUTOPILOT DISENGAGE WARNING lights illuminate steadily.
NOTE: If no keypad entries are made for 5 minutes, the YDC BITE display will turn off. It will be necessary to start over it this occurs.
May 01/00 22-12-01 Page 101
BOEING PROPRIETARY - Copyright . - Unpublished Work - See title page for details.
B. Existing Faults provides detail information on currently existing faults.
(1)
Ensure that the YDC BITE panel displays EXISTING FAULTS? from the main menu. If necessary, press MENU until the main menu appears and scroll using up or down arrows until EXISTING FAULTS? is displayed.
NOTE: Pressing MENU will take the BITE display to the next higher level until the main menu is reached.
(2)
Press YES.
(3)
If no faults are present, the panel displays NO FAULTS. If one or more faults exist, the panel will display the first fault message.
(a) To view details of the fault, press down arrow. MORE DETAILS? will be displayed on the panel. Press YES.
NOTE: Four lines of data are displayed in the MORE DETAILS? screen. Line 1 - Message Number Line 2 - Flight Deck Effect Line 3 - LRU(s) responsible for the fault Line 4 - Fault latched or not latched
1) Press the down arrow key to cycle thru the fault detail lines.
2) Record the maintenance message for future reference.
3) After the last fault detail line, SHOP DETAILS? is displayed on the panel. Press
NO.
4) Observe that the panel displays END OF LIST. Press MENU to return to the EXISTING FAULTS screen. a) If the same fault message is displayed, there are no more faults. b) If a different message is displayed, steps 3(a) thru 3(a)-2 can be repeated
to view details of the next fault.
(b) To bypass the details and view the next fault, scroll until MORE DETAILS? is displayed on the panel. Press NO.
(4) To reset latches, ensure the main menu is displayed on the panel.
(a)
Scroll until EXISTING FAULTS? is displayed. Press YES.
(b)
Cycle thru all (if any) faults until RESET LATCHES is displayed on the panel. Press YES.
(c)
Observe that ARE YOU SURE? is displayed on the panel. Press YES.
(d)
Observe that RESET IN PROGRESS is displayed on the panel. After 2 seconds, ensure that the panel displays NO FAULTS.
中国航空网 www.aero.cn
航空翻译 www.aviation.cn
本文链接地址：737 AMM 飞机维护手册 AUTO FLIGHT 自动飞行 2(54)
