APU AUTO SHUT DOWN - LOW OIL-PRESSURE (APS 3200)

TASK 49-00-00-810-895-A
APU AUTO SHUT DOWN - LOW OIL-PRESSURE (APS 3200)

1. Possible Causes

oil level in the APU oil reservoir is not sufficient
leaks on the oil system components or oil lines
magnetic drain plug
LUBE-PUMP OIL FILTER (8076KM)
Generator Scavenge Filter (8069KM)
wiring
SWITCH-LOP [8091KM]
DE-OILING SOLENOID VALVE (8083KM)
OIL PRESSURE-RELIEF VALVE
GEN-APU [8XS]
APU [4005KM]

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
ESPM 2052210
ESPM 2053210
ESPM 205321A
AMM 24-23-51-000-001	Removal of the APU Generator
AMM 24-23-51-400-001	Installation of the APU Generator
AMM 31-32-00-860-001	Procedure to Get Access to the SYSTEM REPORT/TEST Menu Page
AMM 49-00-00-710-008	Operational Test of the APU
AMM 49-11-11-000-003	Removal of the Power Plant (APU) (APS 3200)
AMM 49-11-11-400-003	Installation of the Power Plant (APU) (APS 3200)
ASM 496102
AMM 49-90-00-600-004	Check Oil Level and Replenish (APS 3200)
AMM 49-91-00-210-002	Visual Inspection of the Lube Pump Filter and Generator-Scavenge Filter Differential-Pressure Indicator Position (APS 3200)
AMM 49-91-42-200-003	Inspection of the Magnetic Drain Plug (APS 3200)
AMM 49-91-43-000-002	Removal of the Pressure Relief Valve (APS 3200)
AMM 49-91-43-400-002	Installation of the Pressure Relief Valve (APS 3200)
AMM 49-91-49-000-002	Removal of the De-oiling Solenoid Valve (APS 3200)
AMM 49-91-49-400-002	Installation of the De-oiling Solenoid Valve (APS 3200)
AMM 49-94-14-000-002	Removal of the Oil Pressure Switch (APS 3200)
AMM 49-94-14-400-002	Installation of the Oil Pressure Switch (APS 3200)

3. Fault Confirmation
Subtask 49-00-00-710-238-A ** ON A/C NOT FOR ALL

A. Do the subsequent checks and the operational test of the APU.
(1) Do a check of the oil level via the MCDU SYSTEM/REPORT TEST page APU:
.push the APU MASTER SW p/bsw to ON,
.select the SYSTEM/REPORT TEST page APU AMM 31-32-00-860-001,
.select the APU DATA/OIL page.

if the oil level in the APU oil reservoir is not sufficient , do the oil servicing AMM 49-90-00-600-004.

(2) Carefully examine the APU externally:

make sure that you do not find leaks on the oil system components or oil lines :

(a) If you find external oil leaks:

correct/replace as necessary.

(3) Do a check of the magnetic drain plug AMM 49-91-42-200-003.
(4) Do a check and make sure that the LUBE-PUMP OIL FILTER (8076KM) and Generator Scavenge Filter (8069KM) are serviceable AMM 49-91-00-210-002.
(5) Do the operational test of the APU AMM 49-00-00-710-008.

NOTE: Operate the APU for 10 minutes minimum under full load. This makes sure that the oil temperature increases sufficiently.

4. Fault Isolation
Subtask 49-00-00-810-146-B ** ON A/C NOT FOR ALL

A. If the APU Last Leg Report gives the maintenance message:

CHECK OIL LEAKAGE / OIL PRESS SW (8091KM):
Fault Code Number: 044 or 045

NOTE: The APU SHUTDOWNS report gives the maintenance message:
LOW OIL PRESSURE - CHECK OIL LEAKAGE / OIL PRESS SW (8091KM)
APU Auto Shut Down Fault Code Number: 044 or 045

do a check and repair the wiring from ECB (59KD) AB/C5,J4 to the OIL PRESSURE SWITCH P14/1,2 ASM 496102. ESPM 2052210 ESPM 2053210 ESPM 205321A.

(1) If the fault continues:

replace the SWITCH-LOP [8091KM] AMM 49-94-14-000-002 and AMM 49-94-14-400-002.

(a) If the fault continues:

replace the DE-OILING SOLENOID VALVE (8083KM) AMM 49-91-49-000-002 and AMM 49-91-49-400-002.

1 If the fault continues:

do a check of the magnetic drain plug AMM 49-91-42-200-003.

2 If the fault continues:

do a check and make sure that the LUBE-PUMP OIL FILTER (8076KM) and Generator Scavenge Filter (8069KM) are serviceable AMM 49-91-00-210-002.

a If the fault continues:

replace the OIL PRESSURE-RELIEF VALVE AMM 49-91-43-000-002 and AMM 49-91-43-400-002.

b If the fault continues:

replace the GEN-APU [8XS] AMM 24-23-51-000-001 and AMM 24-23-51-400-001.

c If the fault continues:

replace the APU [4005KM] AMM 49-11-11-000-003 and AMM 49-11-11-400-003.

Subtask 49-00-00-710-239-A ** ON A/C NOT FOR ALL

B. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:24 UTC