Operational Check of CVDR ULB

TASK 31-39-00-710-803-A
Operational Check of CVDR ULB

WARNING: BE CAREFUL WHEN YOU USE CONSUMABLE MATERIALS. OBEY THE MATERIAL MANUFACTURER'S INSTRUCTIONS AND YOUR LOCAL REGULATIONS.

ZONE: 122
ZONE: 312
FIN: 18TU ** ON A/C NOT FOR ALL
FIN: 19TU ** ON A/C NOT FOR ALL

1. Reason for the Job
Refer to the MPD TASK: 313900-01
OPERATIONAL CHECK OF CVDR ULB.
2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	1	ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE
No specific	1	ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE
No specific	1	WARNING NOTICE(S)
No specific	Torque wrench: range to between 9 and 8 m.N (79.65 and 70.80 lbf.in )
20538-00	1	KIT-TEST, LF ULB

B. Consumable Materials

REFERENCE	DESIGNATION
(Material No.05BAJ1)	Threadlocking Adhesive-- High strength -
(Material No.08BBD1)	Non Aqueous Cleaner-- Isopropyl Alcohol -
(Material No.14SBA1)	Textile-Lint free Cotton -

C. Work Zones and Access Panels

ZONE/ACCESS	ZONE DESCRIPTION
122	AVIONICS COMPARTMENT
312	AFT FUSLG TAIL SECTION

D. 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 31-39-33-000-801-A	Removal of the Cockpit Voice and Data Recorder (CVDR) and the Umbrella Panels
TASK 31-39-33-400-801-A	Installation of the Cockpit Voice and Data Recorder (CVDR) and the Umbrella Panels
TASK 31-39-33-920-801-A	Remove ULB for In Shop Battery Discard
TASK 52-41-00-010-002-A	Open the Avionics Compartment Doors for Access
TASK 52-41-00-410-002-A	Close the Avionics Compartment Doors after Access
TASK 31-39-00-00	COMBINED VOICE AND DATA RECORDING / RECORDING AND AIRCRAFT LOCATING SYSTEM
Underwater Locator Beacon (ULB)
UNDERWATER LOCATOR BEACON (ULB) - TEST TOOL

3. Job Set-up
Subtask 31-39-00-861-052-A ** ON A/C NOT FOR ALL

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

Subtask 31-39-00-010-050-A ** ON A/C NOT FOR ALL

B. Get Access
(1) For the location of this component, refer to paragraph Component Location
(Ref. AMM D/O 31-39-00-00).
(2) Put the WARNING NOTICE(S) in position in the cockpit to tell persons not to operate the flight controls.
(3) Get access to the Cockpit Voice and Data Recorder 2 (CVDR 2):
(a) Put the ACCESS PLATFORM 2M (6 FT) - ADJUSTABLE in position below access door 811.
(b) Open access door 811 (Ref. AMM TASK 52-41-00-010-002).
(4) Get access to the CVDR 1:
(a) Put the ACCESS PLATFORM 3M (10 FT)- ADJUSTABLE in position below access door 312AR.
(b) Open access door 312AR.
(c) Set light switch 3LJ to the ON position.
(d) Remove the CVDR umbrella (Ref. AMM TASK 31-39-33-000-801).

Subtask 31-39-00-020-051-A ** ON A/C NOT FOR ALL

C. Removal of the Underwater Locator Beacon (ULB)

Underwater Locator Beacon (ULB) ** ON A/C NOT FOR ALL

(1) Remove the ULBs (6) from the CVDRs (1) and (2):
(a) Remove the screws (5) from the mounting brackets (4).
(b) Remove the mounting brackets (4) and the nuts (3).
(c) Remove the ULB (6) from the mounting brackets (4).

Subtask 31-39-00-560-052-A ** ON A/C NOT FOR ALL

D. Cleaning of the ULB
(1) Clean the component interfaces and the adjacent area.
(2) Do an inspection of the component interfaces and the adjacent area.
(3) Make sure that the two water switch buttons and the insulation around them are clean and have no grease on them. If necessary, clean them with Non Aqueous Cleaner-- Isopropyl Alcohol - (Material No.08BBD1) and a Textile-Lint free Cotton - (Material No.14SBA1) .

4. Procedure
Subtask 31-39-00-710-053-A ** ON A/C NOT FOR ALL

A. Operational Check
(1) Put the low frequency ULB (1) in servicing operation mode for 60 seconds.
(2) Do the operational test of the ULB (1) of CVDR 1 with the ultrasonic test set:

UNDERWATER LOCATOR BEACON (ULB) - TEST TOOL ** ON A/C NOT FOR ALL

ACTION	RESULT
1.On 20538-00 KIT-TEST, LF ULB (2): Connect the adapter cable (3) to the USB slot of 20538-00 KIT-TEST, LF ULB (2).
2.On 20538-00 KIT-TEST, LF ULB (2): Push the power pushbutton.	On 20538-00 KIT-TEST, LF ULB (2): The screen comes on and shows the brand name. NOTE: 20538-00 KIT-TEST, LF ULB (2) turns off automatically 2 minutes after the last operation.
3.On the screen of 20538-00 KIT-TEST, LF ULB (2): If a low battery indication comes into view, replace the battery of 20538-00 KIT-TEST, LF ULB (2).
4.On the screen of 20538-00 KIT-TEST, LF ULB (2): On the start menu, touch the measurement icon.	On the screen of 20538-00 KIT-TEST, LF ULB (2): The connecting page comes into view.
5.On the ULB (1): Connect the end of the adapter cable (3) to the electrode on the housing of the ULB (1) and hold. Connect the electrode on the top left side of 20538-00 KIT-TEST, LF ULB (2) to the electrode on the battery cap of the ULB (1).	On the screen of 20538-00 KIT-TEST, LF ULB (2): NOTE: The error message "CHECK POLARITY RETRY IN 66 SEC" comes into view when the poles are interchanged. You can start the next measurement after 66 seconds. The progress bar comes into view. After 3 seconds, you hear an acoustic signal. The measurement page comes into view. NOTE: The acoustic signal shows that the measurement is correct.
6.On the ULB (1): Remove the adapter cable (3) from the electrode on the housing of the ULB (1). Make sure that the ULB (1) goes into sleep mode.	On the screen of 20538-00 KIT-TEST, LF ULB (2): NOTE: The error message "READING INCOMPLETE RETRY IN 66 SEC" comes into view when you remove the adapter cable (3) during measurement. You can start the next measurement after 66 seconds. NOTE: To prevent the signal loss, the 20538-00 KIT-TEST, LF ULB (2) must be near the ULB (1). A "SIGNAL OK" tick mark comes into view in the checkbox. NOTE: This "SIGNAL OK" tick mark shows that the functional test is completed and the transmission frequency of the ULB is correct.
7.Do a check of the battery voltage.	Make sure that the battery voltage is not less than 2.8V. If the battery voltage is less than 2.8V, replace the battery (Ref. AMM TASK 31-39-33-920-801)
8.On the screen of 20538-00 KIT-TEST, LF ULB (2): Touch the screen to go back to the start menu page. On the start menu page, touch the memory icon.	On the screen of 20538-00 KIT-TEST, LF ULB (2): The start menu page comes into view, then the memory page. The memory page shows the battery voltage.
9.On the screen of 20538-00 KIT-TEST, LF ULB (2): Touch the screen to go back to the start menu page.	On the screen of 20538-00 KIT-TEST, LF ULB (2): The start menu page comes into view.
10.On 20538-00 KIT-TEST, LF ULB (2): Push the power pushbutton.	On 20538-00 KIT-TEST, LF ULB (2): The screen goes off.
11.On the ULB (1): Make sure that the ULB (1) is deactivated.	NOTE: The ULB (1) goes into sleep mode after 60 seconds.

(3) Do the steps (2)1. thru (2)11. for the ULB (1) of CVDR 2.

Subtask 31-39-00-560-053-A ** ON A/C NOT FOR ALL

B. Inspection of the Attachments of the ULB
(1) Do a visual inspection of the attachment screws and the bracket.
(2) Make sure that the attachment screws and the brackets are clean, and that they show no signs of contamination and deterioration.

5. Close-up
Subtask 31-39-00-420-051-A ** ON A/C NOT FOR ALL

A. Installation of the ULB

Underwater Locator Beacon (ULB) ** ON A/C NOT FOR ALL

(1) Install the ULBs (6) on the CVDRs (1) and (2):
(a) Put the ULB (6) in position on the mounting brackets (4).
(b) Apply a layer of Threadlocking Adhesive-- High strength - (Material No.05BAJ1) to the threads of the screws (5).
(c) Install the nuts (3), the mounting brackets (4) and the screws (5).
(d) Make sure that you can read the ULB identity and the battery expiration-date label.
(e) TORQUE the screws (5) to between 9 and 8 m.N (79.65 and 70.80 lbf.in )

. Obey the torque sequence given on the illustration.

Subtask 31-39-00-410-050-A ** ON A/C NOT FOR ALL

B. Close Access
(1) Make sure that the work area is clean and clear of tools and other items.
(a) Close access to the CVDR 2:
1 Close access door 811 (Ref. AMM TASK 52-41-00-410-002).
(b) Close access to the CVDR 1:
1 Install the CVDR umbrella (Ref. AMM TASK 31-39-33-400-801).
2 Set light switch 3LJ to the OFF position.
3 Close access door 312AR.
(c) Remove the WARNING NOTICE(S).
(d) Remove the access platform(s).

Subtask 31-39-00-862-052-A ** ON A/C NOT FOR ALL

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

[Rev.10 from 2021] 2026.04.01 08:31:34 UTC