Functional Test of the Differential Pressure Sensor (DPS) with the Bleed Test Set P/N 99127B04 and the Bleed Test Kit P/N 99127-281

TASK 36-11-18-720-802-A-01
Functional Test of the Differential Pressure Sensor (DPS) with the Bleed Test Set P/N 99127B04 and the Bleed Test Kit P/N 99127-281

WARNING: MAKE SURE THAT THE PNEUMATIC SYSTEM IS DEPRESSURIZED BEFORE YOU START WORK. PRESSURIZED AIR CAN CAUSE INJURY TO PERSONNEL.

WARNING: BE CAREFUL WHEN YOU DO WORK ON THE ENGINE PARTS AFTER THE ENGINE SHUTDOWN. USE APPLICABLE THERMAL GLOVES. THE ENGINE PARTS CAN STAY HOT FOR ONE HOUR AFTER SHUTDOWN AND CAN BURN YOU.

WARNING: YOU MUST NOT TOUCH HOT PARTS WITHOUT APPLICABLE GLOVES. HOT PARTS CAN CAUSE AN INJURY.

WARNING: MAKE SURE THAT THE SAFETY DEVICES AND THE WARNING NOTICES ARE IN POSITION BEFORE YOU START A TASK ON OR NEAR:

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

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

WARNING: BEFORE YOU INSTALL/REMOVE THE GSE TOOL, READ THE MANUFACTURER'S INSTRUCTIONS, AND, WHILE YOU OPERATE THIS TOOL, CAREFULLY OBEY THEM. IF YOU DO NOT DO THIS, INJURY TO PERSONS AND DAMAGE TO EQUIPMENT CAN OCCUR.

WARNING: BEFORE YOU START WORK, YOU MUST PUT ON A SAFETY HARNESS AND ATTACH IT TO THE ACCESS PLATFORM. WITHOUT A SAFETY HARNESS, YOU CAN FALL. THIS CAN KILL YOU OR CAUSE YOU INJURY.

CAUTION: BE CAREFUL WHEN YOU CONNECT/DISCONNECT THE TEST SET TO/FROM THE EQUIPMENT. THE PRESSURE REGULATING VALVE AND THE PRESSURE GAGE ASSEMBLY OF THE TEST SET ARE HEAVY AND CAN CAUSE DAMAGE TO THE ENGINE.

ZONE: 414
ZONE: 424
FIN: 18HA1
FIN: 18HA2

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

REFERENCE	QTY	DESIGNATION
No specific	AR	ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE
No specific	1	AIR SOURCE - REGULATED, FILTERED, DRY
No specific	AR	CAP - BLANKING
No specific	AR	PLUG - BLANKING
No specific	AR	SAFETY CLIP - CIRCUIT BREAKER
No specific	1	SUPPLY - 28 VDC, ELECTRICAL
No specific	AR	WARNING NOTICE(S)
No specific	Torque wrench: range to between 0.84 and 0.83 m.daN (74.34 and 73.45 lbf.in )
99127-281	1	BLEED TEST KIT
99127B04	1	BLEED TEST SET

B. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
414	UPPER FWD PYLON
424	UPPER FWD PYLON
FOR [18HA1] (XDCR-BLEED DIFFERENTIAL PRESS, ENG1)
414BR
FOR [18HA2] (XDCR-BLEED DIFFERENTIAL PRESS, ENG2)
424BR

C. 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 36-11-00-740-804-A	BITE Test of the Engine Bleed Air System (EBAS) (System Test)
TASK 54-52-11-000-807-A	Removal of the Access Skin Panels
TASK 54-52-11-400-807-A	Installation of the Access Skin Panels
TASK 78-30-00-040-807-A	Deactivation of the Thrust Reverser System for Nacelle Maintenance (ICU)
TASK 78-30-00-440-807-A	Reactivation of the Thrust Reverser System after Nacelle Maintenance (ICU)
DPS with the Bleed Test Set P/N 99127B04 and the Bleed Test Kit P/N 99127-281

3. Job Set-up
Subtask 36-11-18-861-056-A

A. Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).

Subtask 36-11-18-941-056-A

B. Safety Precautions
(1) Make sure that engine 1(2) shutdown occurred not less than 5 minutes before you do this procedure.
(2) On AIR COND panel 30VU:

Make sure that ENG 1(2) BLEED pushbutton switch is released (OFF legend is on).
Make sure that the APU BLEED pushbutton switch is released (ON legend is off).
Put a WARNING NOTICE(S) in position to tell persons not to operate the pneumatic system.

(3) On ENG panel 115VU:

Put a WARNING NOTICE(S) in position to tell the persons not to start engine 1(2).

(4) On the HP ground connector:

Put a WARNING NOTICE(S) in position to tell persons not to pressurize the pneumatic system.

(5) On the ENG section of maintenance panel 50VU:

Make sure that the ON legend of ENG/FADEC GND PWR 1(2) pushbutton switch is off.
Put a WARNING NOTICE(S) in position to tell persons not to energize FADEC 1(2).

Subtask 36-11-18-865-060-A

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

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR BLEED/APU BLEED VLV CTL/BMC1 OVRD	11HV	D14
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20
122VU	AIR BLEED/APU BLEED VLV CTL/BMC2 OVRD	12HV	Z19

Subtask 36-11-18-040-051-A

D. Deactivation of the Thrust Reverser System

WARNING: MAKE SURE THAT THE THRUST REVERSER HYDRAULIC CONTROL UNIT (HCU) IS DEACTIVATED BEFORE YOU DO WORK ON OR AROUND THE THRUST REVERSER. IF THE HCU IS NOT DEACTIVATED, THERE IS A RISK OF UNWANTED THRUST REVERSER OPERATION WHICH CAN CAUSE INJURY TO PERSONS AND/OR DAMAGE TO EQUIPMENT.

(1) Do the deactivation of the thrust reverser system (Ref. AMM TASK 78-30-00-040-807).

Subtask 36-11-18-010-056-A

E. Get Access
(1) Put the ACCESS PLATFORM 5M (16 FT)- ADJUSTABLE in position at the pylon access.
(2) Remove the access panels (Ref. AMM TASK 54-52-11-000-807):
(a) FOR [18HA1] (XDCR-BLEED DIFFERENTIAL PRESS, ENG1)
414BR
(b) FOR [18HA2] (XDCR-BLEED DIFFERENTIAL PRESS, ENG2)
424BR.

4. Procedure
Subtask 36-11-18-480-051-A

A. Preparation of the Functional Test of the DPS

CAUTION: YOU MUST USE THE WRENCH FLATS ON THE MATING PARTS WHEN YOU LOOSEN OR TIGHTEN ANY OR ALL TUBE NUTS. THIS WILL PREVENT ANY TWIST DAMAGE TO THE TUBES.

(1) Use the 99127B04 BLEED TEST SET (T01) with the 99127-281 BLEED TEST KIT to do this test.
(2) On the 99127B04 BLEED TEST SET (T01), make sure that:

Pressure control knobs P1 (2) and P2 (3) are turned fully counterclockwise.
The handles of the shut-off valves (6) and (7) are in the OFF position.
The switches (24) and (25) are in position 2 (OFF).
The knob (38) is in position 0.
The stopwatch switch (19) is down (OFF).
The multimeter knob (41) is in the OFF (vertical) position.
The multimeter switch (28) is in position 1.
The POWER SUPPLY knob (35) is turned fully counterclockwise.
The SQUARE SIGNAL switch (34) is in the OFF position.
The TORQUE MOTOR switch (33) is in the OFF position.
The POWER switch (31) is in the OFF position.

(3) Connect the pneumatic hoses (T04) and (T05):

CAUTION: ONLY USE PNEUMATIC HOSES T04 AND T05 FROM THE LIEBHERR BLEED TEST SET 99127-B04. IF YOU USE DIFFERENT PNEUMATIC HOSES, YOU WILL GET INCORRECT TEST RESULTS.

(a) Make sure that you use the pneumatic hoses (T04) and (T05) available in the 99127B04 BLEED TEST SET (T01).
(4) Connect an AIR SOURCE - REGULATED, FILTERED, DRY to the 99127B04 BLEED TEST SET (T01) pressure input (1) with the pneumatic supply connector (T02):
(a) Make sure that the AIR SOURCE - REGULATED, FILTERED, DRY is set to 0 psi (0.00 bar).
(5) Connect the 28VDC electrical cord (T03) between the 99127B04 BLEED TEST SET (T01) electrical inlet (11) and an external SUPPLY - 28 VDC, ELECTRICAL:
(a) Start the SUPPLY - 28 VDC, ELECTRICAL.
(6) Push the pushbutton (26) and make sure that lights come on from (15) to (21).
(7) Connect the yellow pneumatic hose (T04) between the Y-adaptor (T06) and the 99127B04 BLEED TEST SET (T01) pressure outlet (9).
(8) Connect the red pneumatic hose (T05) between the Y-adaptor (T06) and the 99127B04 BLEED TEST SET (T01) pressure outlet (14).
(9) Disconnect the HP sense line:

CAUTION: USE A SECOND WRENCH TO APPLY COUNTER TORQUE TO THE UNIONS WHEN YOU DISCONNECT/CONNECT THE PNEUMATIC LINES FROM/TO THE UNIONS. IF YOU DO NOT OBEY THIS PRECAUTION, YOU CAN TWIST THE PNEUMATIC LINES AND CAUSE DAMAGE TO THEM.

(a) Disconnect the HP sense line port of the DPS.
(10) Put the PLUG-BLANKING in each disconnected line end.
(11) Connect the test port adaptor (T43) to the HP sense line port of the DPS.
(12) Connect the Y-adaptor (T06) to the test port adaptor (T43).

CAUTION: MAKE SURE THAT THE ELECTRICAL CONNECTORS ARE CLEAN BEFORE YOU DISCONNECT OR CONNECT THEM. CONTAMINATION ON THE ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO EQUIPMENT.

(13) Disconnect electrical connector 18HA1-A (18HA2-A) from the DPS.
(14) Put a CAP - BLANKING on electrical connector 18HA1-A (18AH2-A).

CAUTION: MAKE SURE THAT:

YOU DO NOT APPLY HIGH LOADS WHEN YOU ENGAGE THE TEST PORT ADAPTOR IN THE VALVE OR THE SENSOR
YOU TIGHTEN THE ADAPTOR MANUALLY. IF YOU APPLY A LOAD THAT IS TOO HIGH, DAMAGE TO THE PIN OF THE TEST PORT ADAPTOR CAN OCCUR.

(15) Connect the electrical adaptor (T41) between the DPS and the electrical connector (29) of the 99127B04 BLEED TEST SET (T01), and tighten it with your hand.
(16) Set the digital pressure gage (5) to ON:
(a) Make sure that the pressure value shown on the digital pressure gage (5) is equal to 0 psi (0.00 bar).
(b) If it is not equal to 0 psi (0.00 bar), push and hold the ON/OFF button for 10 seconds.
(17) Pressurize the 99127B04 BLEED TEST SET (T01):

WARNING: BE CAREFUL WHEN YOU PRESSURIZE THE BLEED TEST SET. THE MAXIMUM PRESSURE PERMITTED BY THE BLEED TEST SET IS 290 PSI. PRESSURE HIGHER THAN THE PRESSURE PERMITTED BY THE EQUIPMENT CAN CAUSE INJURY TO PERSONNEL AND/OR DAMAGE TO EQUIPMENT.

(a) Pressurize the 99127B04 BLEED TEST SET (T01) with the AIR SOURCE - REGULATED, FILTERED, DRY to between 100 psi (6.89 bar) and 200 psi (13.79 bar).

Subtask 36-11-18-720-052-A

B. Functional Test of the DPS
(1) Do this test:

ACTION	RESULT
1.On the 99127B04 BLEED TEST SET (T01): Set the POWER switch (31) to the ON position.	On the 99127B04 BLEED TEST SET (T01): The VOLTAGE indicator (37) and the CURRENT indicator (36) come on.
2.On the 99127B04 BLEED TEST SET (T01): Set the multimeter knob (41) to the VDC position.	On the 99127B04 BLEED TEST SET (T01): The multimeter display (42) shows 0.6 and 1.2 V.
3.On the 99127B04 BLEED TEST SET (T01): Set the shut-off valve handle (7) to the ON position Slowly turn the pressure control knob (3) to increase the pressure to 25 -1 psi or +1 psi (1.72 -0.07 bar or +0.07 bar).	On the 99127B04 BLEED TEST SET (T01): The digital pressure gage shows 25 -1 psi or +1 psi (1.72 -0.07 bar or +0.07 bar) The multimeter display (42) shows more than 9.2 V.
4.On the 99127B04 BLEED TEST SET (T01): Slowly turn the pressure control knob (3) to decrease the pressure to 0 psi (0.00 bar). Set the shut-off valve handle (7) to the OFF position.	On the 99127B04 BLEED TEST SET (T01): The digital pressure gage (5) shows 0 psi (0.00 bar).

Subtask 36-11-18-080-053-A

C. Disconnection of the Test Set

WARNING: BEFORE YOU START TO REMOVE THE TOOLING, MAKE SURE THAT THERE IS NO PRESSURIZED GAS LEFT INSIDE THE DUCTS. IT CAN CAUSE AN INJURY TO PERSONNEL AND/OR DAMAGE TO EQUIPMENT.

(1) Make sure that the 99127B04 BLEED TEST SET (T01) shut-off valve is in OFF position and digital pressure gage shows 0 psi (0.00 bar).
(2) Disconnect the Y-adaptor (T06) from the test port adaptor (T43).
(3) Disconnect the test port adaptor (T43) from the HP sense line port of the DPS.
(4) Remove the PLUG-BLANKING from each disconnected line end.
(5) Connect the HP sense line to the HP sense line port of the DPS:

(a) TORQUE the nut of the HP sense line to between 0.84 and 0.83 m.daN (74.34 and 73.45 lbf.in )

.
(6) Disconnect the LP sense line from the DPS.
(7) Put the PLUG-BLANKING in each disconnected line end.
(8) Connect the test port adaptor (T25) to the LP sense line port of the DPS.
(9) Connect the Y-adaptor (T06) to the test port adaptor (T25).

Subtask 36-11-18-720-054-A

D. Functional Test of the DPS
(1) Do this test:

ACTION	RESULT
	On the 99127B04 BLEED TEST SET (T01): The multimeter display (42) shows between 0.6 and 1.2 V.
1.On the 99127B04 BLEED TEST SET (T01): Set the shut-off valve handle (7) to the ON position Slowly turn the pressure control knob (3) to increase the pressure to 20 -1 psi or +1 psi (1.38 -0.07 bar or +0.07 bar).	On the 99127B04 BLEED TEST SET (T01): The digital pressure gage shows 20 -1 psi or +1 psi (1.38 -0.07 bar or +0.07 bar) The multimeter display (42) shows below 0.5 V.
2.On the 99127B04 BLEED TEST SET (T01): Slowly turn the pressure control knob (3) to decrease the pressure to 0 psi (0.00 bar). Set the shut-off valve handle (7) to the OFF position.	On the 99127B04 BLEED TEST SET (T01): The digital pressure gage (5) shows 0 psi (0.00 bar).
3.On the 99127B04 BLEED TEST SET (T01): Set the POWER switch (31) to the OFF position.	On the 99127B04 BLEED TEST SET (T01): The VOLTAGE indicator (37) and the CURRENT indicator (36) go off.

Subtask 36-11-18-080-051-A

E. Disconnection of the Test Set

WARNING: BEFORE YOU START TO REMOVE THE TOOLING, MAKE SURE THAT THERE IS NO PRESSURIZED GAS LEFT INSIDE THE DUCTS. IT CAN CAUSE AN INJURY TO PERSONNEL AND/OR DAMAGE TO EQUIPMENT.

(1) Close the shut-off valve of the AIR SOURCE - REGULATED, FILTERED, DRY to decrease the pressure of the 99127B04 BLEED TEST SET (T01) to 0 psi (0.00 bar).
(2) Disconnect the test port adaptor (T25) from the LP sense line port of the DPS.
(3) Remove the PLUG-BLANKING from each disconnected line end.
(4) Connect the LP sense line to the LP sense line port of the DPS:

(a) TORQUE the nut of the LP sense line to between 0.84 and 0.83 m.daN (74.34 and 73.45 lbf.in )

.
(5) Disconnect the electrical adaptor (T41) from the DPS.
(6) Remove the CAP - BLANKING from the harness electrical connector 18HA1-A (18HA2-A).

CAUTION: MAKE SURE THAT ELECTRICAL CONNECTORS ARE CLEAN WHEN YOU CONNECT THEM. THE CONTAMINATION OF ELECTRICAL CONNECTORS CAN CAUSE DAMAGE TO THE EQUIPMENT.

(7) Connect harness electrical connector 18HA1-A (18HA2-A) to the DPS and tighten it with your hand.
(8) Disconnect the electrical adaptor (T41) from the 99127B04 BLEED TEST SET (T01).
(9) Disconnect the Y-adaptor (T06) from the test port adaptor (T25).
(10) Disconnect the pneumatic hoses (T04) and (T05) from the 99127B04 BLEED TEST SET (T01) and the Y-adaptor (T06).
(11) Disconnect the pneumatic supply connector (T02) from the 99127B04 BLEED TEST SET (T01) and the AIR SOURCE - REGULATED, FILTERED, DRY.
(12) Stop the SUPPLY - 28 VDC, ELECTRICAL.
(13) Disconnect the 28VDC electrical cord (T03) from the SUPPLY - 28 VDC, ELECTRICAL and the 99127B04 BLEED TEST SET (T01).
(14) Disconnect the pneumatic supply connector (T02) from the AIR SOURCE - REGULATED, FILTERED, DRY and the 99127B04 BLEED TEST SET (T01) pressure input (1).
(15) Remove the ground support and maintenance equipment, the special and standard tools and all other items.

Subtask 36-11-18-865-061-A

F. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
49VU	AIR BLEED/APU BLEED VLV CTL/BMC1 OVRD	11HV	D14
49VU	AIR BLEED/X FEED/VALVE/BAT	2HV	D13
49VU	AIR BLEED/ENG 2/MONG	3HA2	D12
49VU	AIR BLEED/ENG 1/CTL	2HA1	D11
122VU	AIR BLEED/ENG 1/MONG	3HA1	Z23
122VU	AIR BLEED/ENG 2/CTL	2HA2	Z22
122VU	AIR BLEED/X FEED VALVE/NORM	1HV	Z20
122VU	AIR BLEED/APU BLEED VLV CTL/BMC2 OVRD	12HV	Z19

Subtask 36-11-18-740-051-A

G. Do the BITE test of the Engine Bleed Air System (EBAS) (Ref. AMM TASK 36-11-00-740-804).

5. Close-up
Subtask 36-11-18-410-054-A

A. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(2) Install the access panels (Ref. AMM TASK 54-52-11-400-807).
(a) FOR [18HA1] (XDCR-BLEED DIFFERENTIAL PRESS, ENG1)
414BR
(b) FOR [18HA2] (XDCR-BLEED DIFFERENTIAL PRESS, ENG2)
424BR.
(3) Remove the access platform(s).
(4) Remove the WARNING NOTICE(S).

Subtask 36-11-18-440-051-A

B. Reactivation of the Thrust Reverser System
(1) Make the thrust reverser serviceable (Ref. AMM TASK 78-30-00-440-807).

Subtask 36-11-18-862-054-A

C. De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 01:08:56 UTC