(3)  
AIPC 73-21-80, Fig. 1

 (4)  
WDM 73-21-71, WDM 73-21-72, WDM 73-21-73, WDM 73-21-74

 (5)  
WDM 77-12-21, WDM 77-12-22

 (6)  
WDM 77-12-23, WDM 77-12-24

 (7)  
SSM 73-21-08, SSM 77-12-21

 B.
Access

 (1)  
Location Zone 115 Area Between Nose Gear Well and Fuselage, LH

 C.
Procedure

 S 424-005-N00
 (1)
Install the applicable engine speed card (AMM 20-11-22/401).

 S 864-006-N00

 (2)  
For the applicable engine, close these circuit breakers and remove the DO-NOT-CLOSE tags:

 (a)  P6 Main Power Distribution Panel
 1) 6K10 SPEED SENSOR ENG 1 1
 2) 6K11 SPEED SENSOR ENG 1 2
 3) 6K12 SPEED SENSOR ENG 2 1
 4) 6K13 SPEED SENSOR ENG 2 2
 5) 6K14 SPEED SENSOR ENG 3 1
 6) 6K15 SPEED SENSOR ENG 3 2
 7) 6K16 SPEED SENSOR ENG 4 1
 8) 6K17 SPEED SENSOR ENG 4 2

 D.
Do a test of the Engine Speed Cards.

 S 864-008-N00
 (1)  Supply the electrical power (AMM 24-22-00/201).
 S 864-022-N00
 WARNING:_______MAKE SURE THAT YOU OPEN THESE CIRCUIT BREAKERS. IF YOU DO NOT REMOVE THE POWER FROM THE PITOT/STATIC, THE AOA, THE TAT AND THE ENGINE P2/T2 PROBES, THEY WILL BECOME HOT DURING THIS PROCEDURE. IF THE PROBES GET HOT, IT CAN CAUSE INJURIES AND DAMAGE TO THE EQUIPMWNT.
 (2)  Open these circuit breakers and install DO-NOT-CLOSE tags:
 (a)  P6 Main Power Distribution Panel
 1) 6D34 PROBE HEAT IND LEFT

 EFFECTIVITYùùùùùùùùùùùùùùùùùùùùùùùùùùùùùù. ú

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////////////////////////A / PW4000 SERIES /747-400 / ENGINES/MAINTENANCE MANUAL ////////////////////////
2) 6D35 PROBE HEAT IND RIGHT
 S 864-023-N00
 (3)  For the applicable engine, open these circuit breakers and install DO-NOT-CLOSE tags:
 (a)  P6 Main Power Distribution Panel
 1) 6H19 PROBE HEAT ENG 1
 2) 6H21 PROBE HEAT ENG 2
 3) 6H23 PROBE HEAT ENG 3
 4) 6H25 PROBE HEAT ENG 4

 S 864-009-N00
 (4)  Erase the EICAS maintenance page.
 (a)  Make sure the applicable ENG (X) SPEED CARD message is not
 displayed.

 S 864-010-N00
 (5)  
Move the channel 1 test switch on the N2 speed card to the TEST position.

 S 864-011-N00

 (6)  
Make sure the applicable ENG (X) SPEED CARD message comes on after 70 seconds.

 S 864-012-N00

 (7)  
Move the channel 1 test switch to the NORMAL position.

 S 864-013-N00

 (8)  
Erase the EICAS maintenance page.

 (a)  Make sure the applicable ENG (X) SPEED CARD message is not
 displayed.

 S 864-014-N00
 (9)  Put the channel 2 test switch to the TEST position.
 NOTE: Hold the channel 2 test switch in the TEST position.
____
 S 864-015-N00
 (10)
 Make sure the applicable ENG (X) SPEED CARD message comes on after 70 seconds.

 S 864-016-N00

 (11)
 Release the channel 2 test switch.

 (a)  Make sure that the switch goes back to the NORMAL position.
 S 864-017-N00
 (12) Erase the EICAS maintenance page.
 (a)  Make sure the applicable ENG (X) SPEED CARD message does not
 come on.

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BOEING PROPRIETARY - Copyright (C) - Unpublished Work - See title page for details.
S 864-018-N00
 (13)
 Close the E/E access door.

 S 864-024-N00

 (14)
 Remove the DO-NOT-CLOSE tags and close these circuit breakers:

 (a)  P6 Main Power Distribution Panel
 1) 6D34 PROBE HEAT IND LEFT
 2) 6D35 PROBE HEAT IND RIGHT