S 845-321

 (4)  
Release the parking brake.

 S 485-322

 (5)  
Install a pressure gage at each of the brake units of the main landing gear (16 locations):

 (a)  
Make sure that the brakes are not operated manually.

 WARNING: THE BRAKES MUST NOT BE IN OPERATION WHEN YOU CONNECT OR
_______ DISCONNECT THE TWO PARTS OF A HYDRAULIC BRAKE DISCONNECT. IF YOU TRY TO CONNECT OR DISCONNECT A HYDRAULIC BRAKE DISCONNECT WITH THE BRAKE IN OPERATION, HYDRAULIC FLUID UNDER HIGH PRESSURE CAN RELEASE. THIS CAN CAUSE INJURY TO PERSONNEL AND DAMAGE TO EQUIPMENT.
 (b)  To remove all pressure from the brake unit, disconnect the hose half of the hydraulic brake disconnect from the brake half.
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 (c)  Remove the brake bleeder assembly from the brake unit housing.
 NOTE: Each brake bleeder assembly has a bleeder valve
____ installed in an adapter. The adapter is installed in the brake unit housing.
 CAUTION: BE CAREFUL DURING INSTALLATION OF THE PRESSURE GAGE IN THE
_______ PORT ON THE BRAKE UNIT HOUSING. DO NOT INSTALL THE PRESSURE GAGE WITH MORE THAN 110 POUND-INCHES OF TORQUE. IF YOU USE TOO MUCH TORQUE DURING INSTALLATION OF A PRESSURE GAGE, YOU CAN DAMAGE THE BRAKE UNIT HOUSING.
 (d)  
Install a pressure gage in the port on the brake unit housing.

 (e)  
Connect the hose half of the hydraulic brake disconnect to the brake half.

 S 845-247
 WARNING: MAKE SURE THAT PERSONS AND EQUIPMENT ARE CLEAR OF ALL CONTROL
_______ SURRACES 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 EQUIPMENT.
 (6)  
Pressurize the applicable hydraulic system (AMM 29-11-00/201).

 (a)  
Pressurize hydraulic system No. 4, to do the test with the normal brake hydraulic system.

 (b)  
Pressurize hydraulic system No. 1 or 2 to do the test with the alternate brake hydraulic system.

 S 845-324
 (7)  Do the steps that follow to supply pressure to the brakes:
 NOTE: Completion of these steps permits pressurization of the
____ brakes without the shutoff valve of the parking brake module closed. This will let hydraulic fluid move freely through the brake return lines when the brakes are released during the test.
 You can also supply pressure to the brakes manually. To do this, the parking brake must be released and you must push one set of brake pedals fully down. This will supply pressure to the brakes. The brake pedals must be held in this position all through the test to supply pressure to the brakes manually.
 (a)  
Make sure this circuit breaker on the Main Power Distribution Panel, P6, is closed: 1) 6L18, PARK BRAKE

 (b)  
If necessary, release the parking brake.

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 (c)  
Open this circuit braker on the P6 panel:
 1) 6L18, PARK BRAKE

 (d)  
Set the parking brake.

 S 845-243
 (8)  
Set the GND TESTS switch on the overhead maintenance panel, P461, to the ENABLE position.

 S 845-245

 (9)  
Prepare the CDU for the test:

 (a)  
Push the MENU key on the CDU to show the MENU.

 (b)  
Push the line select key (LSK) that is adjacent to <CMC to show the CMC MENU.

 (c)  
If <RETURN shows after you push the LSK, push the LSK that is adjacent to <RETURN until you see the CMC MENU.

 (d)  
Push the LSK that is adjacent to <GROUND TESTS to show the GROUND TESTS menu.

 (e)  
　
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