Vacuum Generator Failure

TASK 38-31-00-810-839-A
Vacuum Generator Failure

1. Possible Causes

GENERATOR,VACUUM [37MG]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 23-73-00-740-005	BITE-Test of the Cabin Intercommunication Data System (CIDS) through the CFDS
AMM 38-31-00-710-009	Operational Test of the Toilet Unit
AMM 38-31-00-740-001	BITE Test of the Vacuum Toilet System
AMM 38-31-64-000-001	Removal of the Vacuum Generator
AMM 38-31-64-400-001	Installation of the Vacuum Generator
MCDU Display

3. Fault Confirmation
Subtask 38-31-00-710-125-A ** ON A/C NOT FOR ALL

A. Operational Test
(1) Do a test of the toilet unit AMM 38-31-00-710-009.

NOTE: It is only necessary to do this operational test of the toilet unit if the failure occurs on ground (flight phase 1 = PRE FLIGHT).
On ground the vacuum generator can be enabled after an overheat condition.

Subtask 38-31-00-740-074-A ** ON A/C NOT FOR ALL

B. Tests
(1) Do the CIDS Interface and Power-Up Test AMM 23-73-00-740-005.
(2) Do the procedure to get access to the CFDS SYSTEM REPORT/TEST menu PAGE AMM 38-31-00-740-001.

4. Fault Isolation
Subtask 38-31-00-810-141-A ** ON A/C NOT FOR ALL

A. AFTER FLIGHT:
(1) If the LAST/PREVIOUS LEGS Report gives the maintenance message
VACU GEN (37MG):
(a) Go to the CIDSx-TOILET SYS STATUS page:
If the status page gives the maintenance message VACU GENERATOR: DISABLED
and VACU GEN OVHT: YES
(b) Go to the FAP:
If the FAP gives the maintenance message VACUUM SYSTEM DISABLED ON GROUND:

replace the GENERATOR,VACUUM [37MG] , AMM 38-31-64-000-001 and AMM 38-31-64-400-001.

(2) If the aircraft is on ground (flight phase 1 = PRE FLIGHT):
(a) If the CIDSx-TOILET SYS STATUS page gives the maintenance messages:
VACU GENERATOR: DISABLED and
VACU GEN OVHT: YES
(b) If the FAP gives the maintenance message VACUUM SYSTEM DISABLED ON GROUND:

push the toilet flush switch in one of the lavatories.

NOTE: On ground the vacuum generator can be enabled after an overheat condition.

To reset the messages on the status page and at the FAP:

Do the CIDS Interface and Power-Up Test again.

Subtask 38-31-00-710-126-A ** ON A/C NOT FOR ALL

B. Test
(1) Do the test as given in paragraph 3. A. to check the correct operation.
(2) After the subsequent flight, make sure that the fault does not continue.

[Rev.8 from Aug 2018] 2026.04.04 04:34:15 UTC