32-42-00
ALL ú ú 02 Page 512 ú Jun 15/98
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400
MAINTENANCE MANUAL
S 845-249
WARNING:_______ MAKE SURE THAT PERSONS AND EQUIPMENT ARE CLEAR OF ALL
CONTROL SURFACES BEFORE YOU SUPPLY HYDRAULIC POWER. AILERONS,
RUDDERS, ELEVATORS, FLAPS, SPOILERS, LANDING GEAR, AND THRUST
REVERSERS CAN MOVE QUICKLY WHEN YOU SUPPLY HYDRAULIC POWER.
THIS CAN CAUSE INJURY TO PERSONS AND DAMAGE TO EQUIPMEMNT.
(6)
Pressurize hydraulic system No. 4 (AMM 29-11-00/201).
S 875-317
(7)
Do these steps six times to bleed any small quantities of air from the brakes:
(a)
Slowly push one of the two sets of brake pedals to the limit of travel to fully operate the brakes.
(b)
Hold these brake pedals in this position momentarily.
(c)
Slowly release the brake pedals. Stop for ten seconds before you operate the brakes again.
S 845-251
(8)
Set the parking brake.
S 795-319
(9)
Do a check of the brake bleeder assembly installed on each brake unit housing as follows (16 locations):
(a)
After two minutes with the parking brake set, make sure that there is no leakage at the brake bleeder assembly.
(b)
Make sure that a machine screw is installed in the bleeder valve of the brake bleeder assembly.
S 845-253
(10)
Remove the power from hydraulic system No. 4 (AMM 29-11-00/201).
S 845-255
(11)
Set the GND TESTS switch, on the P461 panel or in the main equipment center, to the NORM position.
S 845-322
(12)
From the GROUND TESTS menu, push the LSK that is adjacent to <RETURN to return to the CMC MENU.
S 845-257
(13)
Remove the electrical power, if it is not necessary (AMM 24-22-00/201).
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32-42-00
ALL ú ú 04 Page 513 ú Oct 10/96
BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
A
747-400 MAINTENANCE MANUAL
TASK 32-42-00-715-324
5. Ground Test - Autobrake Application
___________________________________
A. General
(1)
The Autobrake Application Test is used to verify the autobrake module components (solenoid/control valves/pressure switches) operate correctly. This test will apply an autobrake hydraulic pressure on all brakes based on the selected setting of the autobrake selector switch. For example, the hydraulic pressure applied with autobrake selector switch in the "1" position will be much less than the pressure if the selector switch is in the "MAX" position. If a fault is detected, "AUTOBRAKES" EICAS message will display.
(2)
During the test, the pressure at the brakes is monitored and compared to given values.
(3)
The test is normally completed with the autobrake system set to all possible levels.
(4)
If the results of the ground test are not satisfactory, refer to Fault Isolation Manual, FIM 32-42-00/101, for fault isolation procedures.
(5)
During the ground test, a time of 45 seconds without an input by the user will stop the test. The Control Display Unit (CDU) will then return to the GROUND TESTS menu. If this occurs, the ground test must be started again.
