No PA and no Interphone from both AFT ATTND Stations

TASK 23-73-00-810-902-A
No PA and no Interphone from both AFT ATTND Stations

1. Possible Causes

DEU-B [300RH5]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 23-73-47-000-001	Removal of the Decoder/Encoder Unit B (300RH)
AMM 23-73-47-400-001	Installation of the Decoder/Encoder Unit B (300RH)
AMM 25-62-00-210-001	Check Door and Offwing Escape Slide/Raft Inflation Reservoir Pressure

3. Fault Confirmation
Subtask 23-73-00-710-293-A ** ON A/C NOT FOR ALL

A. Do this test:

ACTION	RESULT
1.On the Programming and Test Panel (PTP):	On the PTP:
push the SYSTEM TEST line select key.	the SYSTEM TEST menu comes on.
push the CONT line select key until the DEU-B line select key comes on.
push the DEU-B line select key.	the DEU-B TEST menu page comes on with a flashing display WAIT FOR RESPONSE. after some seconds the following message comes on: ATA 23-73-47 DEU-B 300RH5

4. Fault Isolation
Subtask 23-73-00-810-608-A ** ON A/C NOT FOR ALL

A. If the DEU-B 300RH5 failure message comes on:

replace the DEU-B [300RH5] AMM 23-73-47-000-001 and AMM 23-73-47-400-001.

NOTE: If no spare DEU-B is available and to avoid AOG due to two inoperative ATTND stations it is possible to swap DEU-B 300RH5 with DEU-B 300RH4.
Ignore the SLIDE PRESS LOW message on the PTP generated by the swapped faulty DEU-B 300RH5. To make sure that the pressure gage of the RH offwing slide inflation-reservoir is in the correct range do the Inspection/Check procedure of the offwing slide inflation-reservoir AMM 25-62-00-210-001.

5. Close-up
Subtask 23-73-00-710-294-A ** ON A/C NOT FOR ALL

A. Do this test:

NOTE: In case you have swapped the DEU-B 300RH5 with DEU-B 300RH4 ignore the failure message generated by the faulty DEU-B on the position of DEU-B 300RH4.

ACTION	RESULT
1.On the Programming and Test Panel (PTP):	On the PTP:
push the SYSTEM TEST line select key.	the SYSTEM TEST menu comes on.
push the CONT line select key until the DEU-B line select key comes on.
push the DEU-B line select key.	the DEU-B TEST menu page comes on with a flashing display WAIT FOR RESPONSE. after some seconds the following message comes on: ATA 23-73-47 TEST OK

[Rev.8 from Aug 2018] 2026.04.04 04:25:56 UTC