(2)  
Remove power from hydraulic system No. 4 (AMM 29-11-00/201).

 (3)  
Set the GND TESTS switch to the NORM position.

 S 845-404
 S 845-403
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 S 845-315
 (4)  
From the GROUND TESTS menu, push the LSK that is adjacent to <RETURN to return to the CMC MENU.

 S 845-316

 (5)  
Remove the electrical power, if it is not necessary
 (AMM 24-22-00/201).

 TASK 32-42-00-715-317
 4. Ground Test - Brake Release
___________________________
 A. General
 (1)  
The Brake Release Test is used to verify the proper operation of each antiskid channel. During this test, the channel selected "<BRAKE 1" will release hydraulic brake pressure for that brake.

 (2)  
When the Alternate Hydraulic system is selected, this test will release hydraulic pressure in tandem pairs. For example, if you select "<BRAKE 1", you will release brake pressure on brakes 1 and 2.

 (3)  
To do the Brake Release Test correctly, you must:

 (a)  
Do the test on the brakes at all wheel locations.

 (b)  
Do the test with the normal and alternate brake hydraulic systems.

 (4)  
The instructions in the procedure indicate that the test must be done on the brakes at all wheel locations. This is the usual procedure, but for fault isolation, you can do the test on only the brakes related to a failure.

 (5)  
If the results of the ground test are not satisfactory, refer to Fault Isolation Manual (FIM) for fault isolation procedures (FIM 32-42-00/101).

 (6)  
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.

 B.
Standard Tools and Equipment

 (1)  
Gage, Hydraulic Pressure, 0-4000 psi with a
 0.5625 (inch)-18 UNF male thread adapter
 (Aeroquip P/N 2266-6-8S) (Quantity 16)

 -Commercially Available
 NOTE: The adapter permits installation of the
____ pressure gage directly in the bleeder assembly port of the brake unit housing.
 C. References
 (1)  
AMM 09-11-00/201, Towing

 (2)  
AMM 24-22-00/201, Manual Control

 (3)  
AMM 29-11-00/201, Main Hydraulic Supply System

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 D. Access
 (1)  
Location Zones
 221 Control Cabin, LH
 222 Control Cabin, RH
 730 Wing Landing Gear - Left and Doors
 740 Wing Landing Gear - Right and Doors
 750 Body Landing Gear - Left and Doors
 760 Body Landing Gear - Right and Doors

 E.
Preconditions

 S 865-410
 (1)  
These preconditions are necessary for this task:

 (a)  
Electrical power is available (AMM 24-22-00/201).

 (b)  
The hydraulic systems are serviceable (AMM 29-11-00/201).

 (c)  
The Control Display Unit (CDU) is serviceable (AMM 34-61-00/501).

 F.
Prepare for the Test

 S 845-318
 (1)  
Make sure that the landing gear ground locks are installed
 (AMM 09-11-00/201).

 S 845-319

 (2)  
Supply electrical power (AMM 24-22-00/201).

 S 845-320

 (3)  
Make sure that wheel chocks are installed.
　
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