PSIU - No Pax Call from one PSIU

TASK 23-73-00-810-875-A
PSIU - No Pax Call from one PSIU

1. Possible Causes

PCB 2038VUA
DEU-A
wiring
PISA

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 23-73-00-810-876-A	PSIU - No Pax Call from two or three PSIUs in series
AMM 23-73-00-710-007	Operational Test of the Passenger Call System
AMM 23-73-00-740-005	BITE-Test of the Cabin Intercommunication Data System (CIDS) through the CFDS
ASM 237313
AMM 23-73-41-000-002	Removal of the Passenger Interface and Supply Adapter
AMM 23-73-41-400-002	Installation of the Passenger Interface and Supply Adapter
AMM 23-73-46-000-001	Removal of the Decoder/Encoder Unit A (200RH)
AMM 23-73-46-400-001	Installation of the Decoder/Encoder Unit A (200RH)
AMM 23-73-49-000-001	Removal of the Printed Circuit Board
AMM 23-73-49-400-001	Installation of the Printed Circuit Board

3. Fault Confirmation
Subtask 23-73-00-710-236-A ** ON A/C NOT FOR ALL

A. Test
(1) Do the CIDS BITE test through the CFDS AMM 23-73-00-740-005.
(2) Do the operational test of the passenger call system AMM 23-73-00-710-007.

Subtask 23-73-00-710-236-C ** ON A/C NOT FOR ALL

A. Test
(1) Do the CIDS Interface and Power-Up Test via the CFDS AMM 23-73-00-740-005.
(2) Do the operational Test of the Passenger Call System AMM 23-73-00-710-007.

4. Fault Isolation
Subtask 23-73-00-810-526-A

A. If the test gives a different maintenance message, do the trouble shooting procedure related to the maintenance message.

Subtask 23-73-00-810-527-A ** ON A/C NOT FOR ALL

B. If the test shows a fault in one PSIU:

replace the PCB 2038VUA AMM 23-73-49-000-001 and AMM 23-73-49-400-001.

(1) If the fault continues:

replace the related DEU-A AMM 23-73-46-000-001 and AMM 23-73-46-400-001.

(a) If the fault continues:

do a check and repair the wiring between the related:
PCB 2038VUA connector 7003VC-A/D and DEU-A connector C/8,C/10 or C/12,
PCB 2038VUA connector 7003VC-A/B and DEU-A connector C/7,C/9 or C/11,
PCB 2038VUA connector 7003VC-A/C and DEU-A connector C/18,C/19 or C/20 ASM 237313.

Subtask 23-73-00-810-527-C ** ON A/C NOT FOR ALL

B. If the test shows a fault in one PSIU:

replace the related PISA AMM 23-73-41-000-002 and AMM 23-73-41-400-002.

Subtask 23-73-00-810-528-A ** ON A/C NOT FOR ALL

C. If the test shows a fault in two or three PSIUs in series on one cabin side:

do the trouble shooting procedures for a fault in two or three PSIUs in series (Ref. TSM TASK 23-73-00-810-876).

Subtask 23-73-00-710-237-A

D. Do the test given in Para. 3.A.

[Rev.8 from Aug 2018] 2026.04.04 04:25:54 UTC