Failure of the Skin Air-Inlet Valve

TASK 21-26-00-810-803-A
Failure of the Skin Air-Inlet Valve

1. Possible Causes

VALVE-SKIN AIR INLET, AVNCS VENT [15HQ]
wiring between the AEVC (10HQ) and the skin air-inlet valve (15HQ)
AEVC [10HQ]
wiring between the AEVC (10HQ) and the SDAC-1 (1WV1) and/or SDAC-2 (1WV2)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 21-26-00-710-001	Operational Check of the Avionics Equipment Ventilation-System via MCDU
AMM 21-26-00-710-008	Operational Test to Read the CFDS for CLASS 3 Faults of the AEVC
AMM 21-26-00-710-009	Operational Test to Read the CFDS for LAST LEG REPORT of the AEVC
ASM 212602
ASM 212603
AMM 21-26-34-000-001	Removal of the Avionics Equipment Ventilation Computer (AEVC)
AMM 21-26-34-400-001	Installation of the Avionics Equipment Ventilation Computer (AEVC)
AMM 21-26-42-200-001	Inspection/Check of the Skin Heat Exchanger (Inlet Duct)
AMM 21-26-52-000-001	Removal of the Avionics-Ventilation Skin Air-Inlet-Valve
AMM 21-26-52-400-001	Installation of the Avionics-Ventilation Skin Air-Inlet-Valve
AMM 21-26-56-000-001	Removal of the Air Inlet Check Valve
AMM 21-26-56-400-001	Installation of the Air Inlet Check Valve

3. Fault Confirmation
Subtask 21-26-00-865-057-A

A. Table of the circuit breakers used in this procedure:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C ALL
122VU	AIR COND/AVNCS/VENT/MONG	3HQ	Y17

Subtask 21-26-00-710-078-A

B. Test
(1) Do the reset of the AEVC (10HQ).
(a) Open the circuit breaker AIR COND/AVNCS/VENT/MONG (3HQ).
(b) Wait for five seconds.
(c) Close the circuit breaker AIR COND/AVNCS/VENT/MONG (3HQ).
(2) Do the operational test of the avionics equipment ventilation from the Multipurpose Control and Display Unit (MCDU) AMM 21-26-00-710-001.
(3) Read the LAST LEG REPORT of the AEVC AMM 21-26-00-710-009.
(4) Read the CLASS 3 faults of the AEVC AMM 21-26-00-710-008.

4. Fault Isolation
Subtask 21-26-00-810-102-A

A. If the test gives the maintenance message SKIN AIR INLET V 15HQ and the logbook or the Post Flight Report (PFR) gives the ECAM warning VENT BLOWER FAULT:

Replace the VALVE-SKIN AIR INLET, AVNCS VENT [15HQ] AMM 21-26-52-000-001 AMM 21-26-52-400-001.
Replace the air-inlet check valve (2150HM) AMM 21-26-56-000-001 AMM 21-26-56-400-001.
Do a check of the skin heat exchanger (inlet duct) AMM 21-26-42-200-001.

Subtask 21-26-00-810-066-A

B. If the test gives the maintenance message SKIN AIR INLET V 15HQ and the logbook or the Post Flight Report (PFR) does not give the ECAM warning VENT BLOWER FAULT:

Do a check of the status of the skin air-inlet valve (15HQ) on the lower ECAM display unit.

(1) If the valve symbol is green:

Do a check and repair the wiring between the AEVC (10HQ) and the skin air-inlet valve (15HQ) ASM 212603:
. Pin AA/4B and pin A/C
. Pin AA/4A and pin A/A.

(2) If the valve symbol is amber:

Do a check and repair the wiring between the AEVC (10HQ) and the skin air-inlet valve (15HQ) ASM 212603:
. Pin AB/4B and pin A/M
. Pin AB/4A and pin A/J.

(3) If the fault continues:

Replace the VALVE-SKIN AIR INLET, AVNCS VENT [15HQ] AMM 21-26-52-000-001 and AMM 21-26-52-400-001.

(a) If the fault continues:

Replace the AEVC [10HQ] AMM 21-26-34-000-001 and AMM 21-26-34-400-001.

(4) If the fault continues:

Do a check and repair the wiring between the AEVC (10HQ) and the SDAC-1 (1WV1) and/or SDAC-2 (1WV2), pin AB/8A and pin AD/12C ASM 212602.

Subtask 21-26-00-710-079-A

C. Do the operational test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:24:36 UTC