Functional Test of The Brake Cooling System

TASK 32-48-00-710-001-A
Functional Test of The Brake Cooling System

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 32-00-00-860-001-A	Flight Configuration Precautions with Electrical Power
TASK 32-00-00-860-001-A-01	Flight Configuration Precautions without Electrical Power
TASK 32-00-00-860-002-A	Ground Configuration after Flight Configuration with Electrical Power
TASK 32-00-00-860-002-A-01	Ground Configuration after Flight Configuration without Electrical Power

3. Job Set-up
Subtask 32-48-00-860-050-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) On the panel 402VU, make sure that the BRK FAN CONTROL pushbutton switch is released.
(2) Energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-861-002).
(3) Take the applicable safety precautions before you open the LGCIU circuit breakers (Ref. AMM TASK 32-00-00-860-001).

Subtask 32-48-00-865-055-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	LIGHTING/XFMR/115V.5V/ESS BUS	29LP	H03
** ON A/C NOT FOR ALL
49VU	LIGHTING/XFMR/115V.5V/ESS BUS	29LP	H01
** ON A/C NOT FOR ALL
121VU	LGCIU/BAT SPLY/SYS2	59GA	R33
** ON A/C NOT FOR ALL
121VU	HYDRAULIC/BRK FAN/WHEELS/3 AND 4	2GS	L35
121VU	HYDRAULIC/BRK FAN/WHEELS/1 AND 2	1GS	L32
121VU	HYDRAULIC/BRK/FAN/CTL	3GS	M32
121VU	HYDRAULIC/LGCIU/SYS2	2GA	Q35
121VU	HYDRAULIC/LGCIU/SYS1/GRND SPLY	52GA	Q34
** ON A/C NOT FOR ALL
121VU	LGCIU/BAT SPLY/SYS2	59GA	R32
** ON A/C NOT FOR ALL
122VU	LIGHTING/TST/BOARD/SPLY	30LP	X06
122VU	LIGHTING/ANN LT SPLY/XFMR/BUS 2	27LP	X05
122VU	LIGHTING/ANN LT SPLY/XFMR/BUS 1	26LP	X04
122VU	LIGHTING/ANN LT SPLY/XFMR/STAT INV	28LP	X03

4. Procedure
Subtask 32-48-00-710-050-A ** ON A/C NOT FOR ALL

A. Test of the BRK FAN CONTROL Pushbutton Switch

ACTION	RESULT
1.On the panel 25VU, put the ANN LT selector switch in the TEST position.	The ON and HOT legends of the BRK FAN CONTROL pushbutton switch come on.
2.On the panel 25VU, put the ANN LT selector switch in the BRT position.	The ON and HOT legends of the BRK FAN CONTROL pushbutton switch go off.
3.On the panel 402VU, push the BRK FAN CONTROL pushbutton switch.	On this pushbutton switch, the ON legend comes on.
4.On the panel 25VU, put the BRT/DIM selector switch in the DIM position and then in the BRT position.	The ON legend of the BRK FAN CONTROL pushbutton switch gets dimmer then gets fully bright.
5.On the panel 402VU, release the BRK FAN CONTROL pushbutton switch.	On this pushbutton switch, the ON legend goes off.

Subtask 32-48-00-710-051-C ** ON A/C NOT FOR ALL

B. Test of the brake cooling system.

ACTION	RESULT
1.On the panel 121VU, open the circuit breaker 2GS. On the panel 402VU, push the BRK FAN CONTROL pushbutton switch.	On this pushbutton switch, the ON legend comes on. On the wheels 1 and 2 of the left main landing gear, make sure that the fans operate correctly. Make sure that the air flows in the correct direction. (from in the wheel to out of the wheel).
2.On the panel 402VU, release the BRK FAN CONTROL pushbutton switch.	On this pushbutton switch, the ON legend goes off. The fans of the wheels 1 and 2 stop.
3.On the panel 121VU, open the circuit breaker 1GS and close the circuit breaker 2GS. Do the test specified in paragraphs 1 and 2, for wheels 3 and 4 only.	You must get the same results as paragraphs 1 and 2, for wheels 3 and 4 only.
4.Close the circuit breakers 1GS and make sure that the circuit breaker 2GS and 3GS are closed. On the panel 402VU, push the BRK FAN CONTROL pushbutton switch.	On this pushbutton switch, the ON legend comes on. Make sure that the fans on the four wheels operate correctly.
5.On the panel 121VU, open the circuit breaker 3GS.	The fans on the four wheels stop.
6.On the panel 121VU, close the circuit breaker 3GS.	On the four wheels, the fans operate.
7.On the panel 121VU, open the circuit breakers 2GA and 59GA to do the simulation of the landing gear not downlocked.	Make sure that the four fans stop.
8.On the panel 121VU, close the circuit breakers 2GA and 59GA.	Make sure that the fans operate.
9.On the panel 402VU, release the BRK FAN CONTROL pushbutton switch.	On this pushbutton switch, the ON legend goes off. On the four wheels, the fans stop.

Subtask 32-48-00-860-051-A ** ON A/C NOT FOR ALL

C. Aircraft Maintenance Configuration
(1) After you close the LGCIU circuit breakers, put the aircraft back to the correct (ground) condition (Ref. AMM TASK 32-00-00-860-002).
(2) De-energize the aircraft electrical circuits (Ref. AMM TASK 24-41-00-862-002).

5. Close-up
Subtask 32-48-00-942-052-A ** ON A/C NOT FOR ALL

A. Removal of Equipment
(1) Make sure that the work area is clean and clear of tools and other items.

[Rev.10 from 2021] 2026.04.01 00:50:32 UTC