Removal of the Micro-switch

TASK 28-25-71-000-001-A
Removal of the Micro-switch

WARNING: PUT THE SAFETY DEVICES AND THE WARNING NOTICES IN POSITION BEFORE YOU START A TASK ON OR NEAR:

THE FLIGHT CONTROLS
THE FLIGHT CONTROL SURFACES
THE LANDING GEAR AND THE RELATED DOORS
COMPONENTS THAT MOVE.

MOVEMENT OF COMPONENTS CAN KILL OR CAUSE INJURY TO PERSONS AND/OR CAN CAUSE DAMAGE TO THE EQUIPMENT.

WARNING: MAKE SURE THAT THE GROUND SAFETY-LOCKS ARE IN POSITION ON THE LANDING GEAR. THIS WILL PREVENT UNWANTED MOVEMENT OF THE LANDING GEAR, AND THUS POSSIBLE INJURY TO PERSONS AND DAMAGE TO THE AIRCRAFT AND/OR EQUIPMENT.

FIN: 20QU

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 3M (10 FT)
No specific	AR	CAP - BLANKING
No specific	AR	SAFETY BARRIER(S)
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	WARNING NOTICE(S)
98D27803500001	1	LOCKING TOOL ZERO POS

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
622KB
192MB

C. Referenced Information

REFERENCE	DESIGNATION
Micro-switch 20QU ** ON A/C NOT FOR ALL
Micro-switch 20QU ** ON A/C NOT FOR ALL

3. Job Set-up
Subtask 28-25-71-941-052-A ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.

Subtask 28-25-71-941-052-B ** ON A/C NOT FOR ALL

A. Safety Precautions
(1) As necessary, use the applicable SAFETY BARRIERS, specified by the operator's instructions and your local regulations.
(2) Put the WARNING NOTICE(S) in position to tell persons not to operate the slats.

Subtask 28-25-71-860-050-B ** ON A/C NOT FOR ALL

B. Aircraft Maintenance Configuration
(1) Install the 98D27803500001 LOCKING TOOL ZERO POS on the slat/flap control lever.

Subtask 28-25-71-010-050-A ** ON A/C NOT FOR ALL

C. Get Access
(1) Open the access door 192MB.

NOTE: If operating in battery power, do not keep the door open longer than necessary because the battery can discharge.

Subtask 28-25-71-010-050-B ** ON A/C NOT FOR ALL

C. Get Access
(1) Put the ACCESS PLATFORM 3M (10 FT) in position below zone 622.
(2) Open the access door 622KB.

NOTE: If operating in battery power, do not keep the door open longer than necessary because the battery can discharge.

Subtask 28-25-71-865-050-A

D. Open, safety and tag this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	FUEL/FQI/CHAN/1	1QT	A13
** ON A/C NOT FOR ALL
121VU	FUEL/FQI/CHANNEL/1 AND 2	8QT	L26
121VU	FUEL/RFL/DFL/SPLY	2QU	L24
** ON A/C ALL
121VU	FUEL/FQI/CHAN/2	2QT	M27
** ON A/C NOT FOR ALL
121VU	FUEL/FQI/CHANNEL/1 AND 2	8QT	L25
121VU	FUEL/RFL/DFL/SPLY	2QU	L23
** ON A/C ALL
122VU	ELEC/REFLNG/NORM	2PR	S27
122VU	ELEC/RFL/SPLY/LOGIC	4PR	U29
122VU	ELEC/REFLNG/ON/BAT	1PR	U28

4. Procedure
Subtask 28-25-71-020-050-B ** ON A/C NOT FOR ALL

A. Removal of the Micro-switch 20QU

WARNING: USE PROTECTIVE GOGGLES AND GLOVES WHEN YOU REMOVE OR INSTALL LOCKWIRE. EACH TIME YOU CUT LOCKWIRE, REMOVE AND DISCARD IT IMMEDIATELY. LOOSE LOCKWIRE CAN CUT YOU OR MAKE YOU BLIND, AND/OR CAN CAUSE DAMAGE.

(1) Remove the cable-tie that holds the support cable and the connector-plug (1) in position.
(2) Disconnect the electrical connector (1) from the micro-switch (7).
(3) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(4) Remove and discard the lockwire from the locknut (6) and the lockwasher (5).
(5) Remove the locknut (6), the lockwasher (5) and the position-washer (4) from the microswitch (7).
(6) Carefully remove the micro-switch (7) from the bracket (2).

Subtask 28-25-71-020-050-C ** ON A/C NOT FOR ALL

A. Removal of the Micro-switch 20QU

(1) Disconnect the electrical connector (11) from the micro-switch (1).
(2) Put the CAP-BLANKING on each disconnected electrical connector and receptacle.
(3) Remove and discard the lockwire from the locknut (4) and the lockwasher (3).
(4) Remove the locknut (4), the lockwasher (3) and the position-washer (2) from the microswitch (1).
(5) Carefully remove the micro-switch (1) from the bracket (10).

[Rev.10 from 2021] 2026.04.02 06:17:44 UTC