APU AUTO SHUTDOWN - INLET OVERHEAT, APU Inlet Temperature higher than Limit (131-9(A))

TASK 49-00-81-810-843-A
APU AUTO SHUTDOWN - INLET OVERHEAT, APU Inlet Temperature higher than Limit (131-9(A))

1. Possible Causes

NO LRU FAULT DETECTED
blockage of the APU inlet
fire of the APU inlet
damage/contamination of the electrical connector P6
aircraft wiring
APU INLET TEMPERATURE SENSOR (P6)
ELECTRONIC CONTROL BOX [59KD]
APU [4005KM]
APU INLET TEMPERATURE SENSOR (8010KM).

2. Job Set-up Information
A. Fixtures, Tools, Test and Support Equipment

REFERENCE	QTY	DESIGNATION
No specific	AR	JUMPER-WIRE
No specific	AR	MULTIMETER - STANDARD

B. Referenced Information

REFERENCE	DESIGNATION
AMM 49-00-00-860-008	APU Start by External Power
AMM 49-11-11-000-004	Removal of the Power Plant (APU) (131-9(A))
AMM 49-11-11-400-004	Installation of the Power Plant (APU) (131-9(A))
AMM 49-23-14-000-001	Removal of the Sensor-APU Inlet Temperature (131-9(A))
AMM 49-23-14-400-001	Installation of the Sensor-APU Inlet Temperature (131-9(A))
AMM 49-61-34-000-003	Removal of the Electronic Control Box (ECB) (131-9(A))
AMM 49-61-34-400-003	Installation of the Electronic Control Box (ECB) (131-9(A))

3. Fault Confirmation
Subtask 49-00-81-710-176-A ** ON A/C NOT FOR ALL

A. Read-out of ECB Trouble-Shooting Data
(1) Put the APU MASTER SW to the ON position.
(2) Get access to the APU SHUTDOWN report.
(3) Push the '>' adjacent to LRU DATA:

the MCDU menu shows
NO LRU FAULT DETECTED

(4) Start the APU and apply Bleed Air for 20 seconds, minimum AMM 49-00-00-860-008.

4. Fault Isolation
Subtask 49-00-81-810-124-A ** ON A/C NOT FOR ALL

A. If an APU auto shutdown occurs during the APU operation and the APU SHUTDOWN report gives the maintenance message:

INLET OVERHEAT
CHECK APU INLET

associated with Fault Code Numbers (FCN) 213

do a check for blockage of the APU inlet .

(1) If the fault continues:

do a check for a fire of the APU inlet :
- do a check of the inlet plenum for fire damage.
- do a check of the APU inlet duct through the inlet flap for fire damage.

(a) If there are signs of fire damage:

replace the APU (4005KM) AMM 49-11-11-000-004 and AMM 49-11-11-400-004.

(b) If there are no signs of fire damage:

do a check for damage/contamination of the electrical connector P6 of the APU INLET TEMPERATURE SENSOR (P6).

1 If the electrical connector P6 is damaged/contaminated:

do a repair/cleaning.

2 If the electrical connector is OK:

disconnect the electrical connector P6
put a JUMPER-WIRE across the sockets A and B of the electrical connector P6.
use a MULTIMETER - STANDARD to do a resistance check of the aircraft wiring across the ECB (59KD) AB/H4 to ECB (59KD) AB/H3.

a If the resictance value is > 10 Ohms:

replace the aircraft wiring.

b If the fault continues:

replace th APU INLET TEMPERATURE SENSOR (P6) AMM 49-23-14-000-001 and AMM 49-23-14-400-001.

c If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] of the APU [4005KM] AMM 49-61-34-000-003 and AMM 49-61-34-400-003.

Subtask 49-00-81-810-124-B ** ON A/C NOT FOR ALL