Liquid Level Transmitter Failure

TASK 38-31-00-810-804-A
Liquid Level Transmitter Failure

1. Possible Causes

XMTR-LEVEL [40MG]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
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 38-31-62-000-001	Removal of the Liquid Level Transmitter
AMM 38-31-62-400-001	Installation of the Liquid Level Transmitter
MCDU Display ** ON A/C NOT FOR ALL
MCDU Display ** ON A/C NOT FOR ALL

3. Fault Confirmation
Subtask 38-31-00-710-053-A ** ON A/C NOT FOR ALL

A. Do the operational test of the vacuum toilet system AMM 38-31-00-710-009.

Subtask 38-31-00-740-053-A ** ON A/C NOT FOR ALL

B. Do the bite test AMM 38-31-00-740-001.

4. Fault Isolation
Subtask 38-31-00-810-082-B ** ON A/C NOT FOR ALL

A. If the operational test is OK:

Refer bite test last leg or previous legs report.
MCDU Display ** ON A/C NOT FOR ALL
MCDU Display ** ON A/C NOT FOR ALL

(1) If the LAST LEG REPORT or PREVIOUS LEG REPORT page gives the maintenance message LIQD LVL XMTR:

do a check of the differential pressure line and the flexible hose P/N MTR1008-001 for possible damage. If necessary, replace the hose or line.
If the fault continues:

(a) clean and fully dry the inside of the differential pressure vent line.
(2) If the fault continues:

do a check of the electrical connections of the small connector 40MG/A.

(3) If the electrical connections are OK:

replace the XMTR-LEVEL [40MG] , AMM 38-31-62-000-001 and AMM 38-31-62-400-001.

Subtask 38-31-00-710-065-A ** ON A/C NOT FOR ALL

B. Test
(1) Do the operational test of the vacuum toilet system and make sure it operates correctly AMM 38-31-00-710-009.
(2) After the subsequent flight, make sure that the fault does not continue.

[Rev.8 from Aug 2018] 2026.04.04 04:34:12 UTC