APU AUTO SHUT DOWN - OVERTEMPERATURE, Inlet Guide Vane Actuator Fault (with AIDS support) (APS 3200)

TASK 49-00-00-810-905-A-01
APU AUTO SHUT DOWN - OVERTEMPERATURE, Inlet Guide Vane Actuator Fault (with AIDS support) (APS 3200)

1. Possible Causes

APU [4005KM]
INLET GUIDE-VANE ACTUATOR (8014KM)
fuel leaks
ELECTRONIC CONTROL BOX [59KD]
FUEL CONTROL UNIT (8022KM)

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TSM TASK 28-22-00-810-801-A	APU Fuel System - Low Pressure
AMM 28-22-00-710-002	Operational Test of the APU Fuel-Pump System
AMM 31-36-00-740-008	Access to the Parameter Call-Up Menus
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)
AMM 49-23-51-000-003	Removal of the Inlet Guide Vane Actuator (APS 3200)
AMM 49-23-51-400-003	Installation of the Inlet Guide Vane Actuator (APS 3200)
AMM 49-23-51-710-001	Push/Pull Test of the Inlet Guide Vane Mechanism (APS 3200)
AMM 49-32-11-000-002	Removal of the Fuel Control Unit (APS 3200)
AMM 49-32-11-400-002	Installation of the Fuel Control Unit (APS 3200)
AMM 49-61-34-000-002	Removal of the Electronic Control Box (ECB) (APS 3200)
AMM 49-61-34-400-002	Installation of the Electronic Control Box (ECB) (APS 3200)

3. Fault Confirmation
Subtask 49-00-00-710-376-A ** ON A/C NOT FOR ALL

A. Check/Test
(1) Get access to the AIDS parameters (ALPHA CALL UP) AMM 31-36-00-740-008.
(a) Record the parameter IGV (APU Inlet Guide Vanes)

during APU start
and
during APU operation.

(2) Do the operational test of the APU AMM 49-00-00-710-008.

NOTE: Make sure that the fuel supply to the APU is correct AMM 28-22-00-710-002. If the fuel supply is not correct, do the trouble shooting of APU low fuel pressure (Ref. TSM TASK 28-22-00-810-801).

4. Fault Isolation
Subtask 49-00-00-810-341-B ** ON A/C NOT FOR ALL

A. If an APU auto shutdown occurs during the operational test of the APU and the APU SHUTDOWNS report gives the maintenance message:

OVERTEMPERATURE - INLET GUIDE VANE ACTR P21

and the IGV parameter is less than
72 deg (+/- 2 deg) during APU start sequence
or
82 deg during APU run (without load):

do the push/pull test of the IGV mechanism AMM 49-23-51-710-001.

(1) If the push/pull test fails:

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

(2) If the push/pull test is OK:

replace the INLET GUIDE-VANE ACTUATOR (8014KM) AMM 49-23-51-000-003 and AMM 49-23-51-400-003.

(3) If the fault continues:

do a check of the fuel lines from the FCU (8022KM) to the IGV actuator (8014KM).
fuel leaks are not permitted, correct/replace as necessary.

(4) If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.

Subtask 49-00-00-810-342-B ** ON A/C NOT FOR ALL

B. If an APU auto shutdown occurs during the operational test of the APU and the APU SHUTDOWNS report gives the maintenance message:

0VERTEMPERATURE - INLET GUIDE VANE ACTR P21

and the IGV parameter is
72 deg (+/- 2 deg) during APU start sequence
and
82 deg during APU run (without load):

replace the FUEL CONTROL UNIT (8022KM) AMM 49-32-11-000-002 and AMM 49-32-11-400-002.

(1) If the fault continues:

replace the ELECTRONIC CONTROL BOX [59KD] AMM 49-61-34-000-002 and AMM 49-61-34-400-002.

Subtask 49-00-00-710-377-A ** ON A/C NOT FOR ALL

C. Do the test given in Para. 3.

[Rev.8 from Aug 2018] 2026.04.04 04:34:25 UTC