NOTE:  MASTER CAUTION and OVHD annunciator lights may remain on due to signals from other systems.
4) ISOLATION VALVE light
5) Both REVERSER UNLOCKED lights

(2)  Test thrust reverser indication system as follows:
(a)  
Press either MASTER CAUTION light and verify that both MASTER CAUTION lights and all master caution annunciator lights remain off.

(b)  
Press to test ISOLATION VALVE and both REVERSER UNLOCKED lights and verify that they illuminate.

(c)  
Position the LIGHTS switch on the P2 panel to TEST. The following lights shall illuminate: 1) Deleted. 2) ISOLATION VALVE light 3) Both REVERSER UNLOCKED lights 4) Both MASTER CAUTION lights 5) OVHD annunciator light

(d)  
Return the LIGHTS switch on the P2 panel to BRT. All lights shall extinguish.

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NOTE:  MASTER CAUTION and OVHD annunciator lights may remain on due to signals from other systems. If this occurs, extinguish these lights by pressing either MASTER CAUTION light.
(3)  
Test engine override switch operation as follows:

(a)  
Rotate both reverse thrust levers aft to interlock stop. (Angular travel of reverse thrust lever from OFF to INTERLOCK is approximately 90 degrees.) 1) Thrust reverser deflector doors shall remain stowed, and all lights shall remain

extinguished.

(b)  
Rotate both reverse thrust levers to the OFF position.

(4)  
Test engine No. 1 thrust reverser operation as follows:

(a)  
Position engine No. 1 thrust reverser override switch to OVERRIDE. 1) ISOLATION VALVE light will remain off. 2) Forward thrust levers will be free to advance. (Return levers to IDLE STOP after

trial movement.)

(b)  
Rotate reverse thrust levers rapidly aft to limits of travel.

1)  Engine No. 1 thrust reverser shall deploy fully within 2 seconds after completion of thrust lever movement.
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2)  Engine No. 1 reverse thrust lever shall be free to rotate aft to the reverse thrust temperature indicating detent. Aft rotation of engine No. 2 reverse thrust lever shall be limited by the interlock cam and engine No. 2 thrust reverser shall remain stowed.
3)  Engine No. 1 REVERSER UNLOCKED light will illuminate.
(c)  Rotate both reverse thrust levers rapidly to the OFF position. 1) Engine No. 1 thrust reverser shall fully stow within 3 seconds after completion of
reverse thrust lever movement. 2) Engine No. 1 REVERSER UNLOCKED light will extinguish. 3) Forward thrust levers will be free to advance. (Return levers to IDLE STOP after
trial movement.)
(d)  Position engine No. 1 thrust reverser override switch to NORMAL.
NOTE: ISOLATION VALVE light may come on momentarily.
(5)  
For engine No. 2 thrust reverser operational test, follow the same procedure outlined in step (4) using the No. 2 override switch, and monitoring the No. 2 REVERSER UNLOCKED light.

(6)  
Verify operation of biased shuttle valves by operating thrust reversers with standby hydraulic system pressurized in addition to A and B systems.

(a)  
With landing gear selector lever in DOWN position, pressurize standby hydraulic system.

(b)  
Position engine No. 1 thrust reverser override switch to OVERRIDE and engine No. 2 override switch to NORMAL.

(c)  
Rotate both reverse thrust levers rapidly aft to limits of travel.

1)  Engine No. 1 thrust reverser shall deploy fully within 2 seconds of completion of thrust lever movement.
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2)  Engine No. 1 reverse thrust lever shall be free to rotate aft to the No. 2 detent. Aft rotation of engine No. 2 reverse thrust lever shall be limited by the interlock cam and engine No. 2 thrust reverser shall remain stowed.
3)  Engine No. 1 REVERSER UNLOCKED light shall illuminate.
(d)  Rotate both reverse thrust levers rapidly to the OFF position. 1) Engine No. 1 thrust reverse shall fully stow within 3 seconds of completion of
lever movement. 2) Engine No. 1 REVERSER UNLOCKED light shall extinguish. 3) Forward thrust levers will be free to advance. (Return levers to IDLE STOP after
trial movement.)
(e)  
Position engine No. 1 thrust reverser override switch to NORMAL.