Functional Test of the APU Main Engine Start (MES) Mode

TASK 49-00-00-720-802-A
Functional Test of the APU Main Engine Start (MES) Mode

1. Reason for the Job
Self explanatory
2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
TASK 24-41-00-861-002-A	Energize the Aircraft Electrical Circuits from the External Power
TASK 24-41-00-861-002-A-01	Energize the Aircraft Electrical Circuits from the APU
TASK 24-41-00-861-002-A-02	Energize the Aircraft Electrical Circuits from Engine 1(2)
TASK 24-41-00-862-002-A	De-energize the Aircraft Electrical Circuits Supplied from the External Power
TASK 24-41-00-862-002-A-01	De-energize the Aircraft Electrical Circuits Supplied from the APU
TASK 24-41-00-862-002-A-02	De-energize the Aircraft Electrical Circuits Supplied from the Engine 1(2)
TASK 31-36-00-740-008-A	Access to the Parameter Call-Up Menus
TASK 31-60-00-860-001-A	EIS Start Procedure
TASK 31-60-00-860-002-A	EIS Stop Procedure
TASK 49-00-00-710-009-A	Self-Test of the ECB
TASK 49-00-00-860-008-A	APU Start by External Power
TASK 49-00-00-860-008-A-01	APU Start by Batteries
TASK 49-00-00-860-009-A	APU Shutdown by External Power (131-9(A))
TASK 49-00-00-860-009-A-01	APU Shutdown by Batteries (131-9(A))

3. Job Set-up
Subtask 49-00-00-860-196-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-861-002).
(2) Do the EIS start procedure (upper ECAM DU and lower ECAM DU only)
(Ref. AMM TASK 31-60-00-860-001).

Subtask 49-00-00-865-192-A ** ON A/C NOT FOR ALL

B. Make sure that this(these) circuit breaker(s) is(are) closed:

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
49VU	APU/FUEL/BLOW OFF/PUMP	2QC	B14
** ON A/C NOT FOR ALL
121VU	APU/FUEL/BLOW OFF/CTL	1QC	K39
** ON A/C NOT FOR ALL
121VU	APU/FIRE AND OVHT/DET/LOOP B	2WG	L44
121VU	APU/FIRE AND OVHT/DET/LOOP A	1WG	L43
121VU	APU/APU/CTL	2KD	L42
121VU	APU/ECB/SPLY	1KD	L41
121VU	APU/FIRE/EXTIG/SQUIB/B	2WF	L39
121VU	APU/FIRE/EXTIG/SQUIB/A	1WF	L38
121VU	APU/FIRE/LP VALVE/NORM	4WF	M42
121VU	APU/FIRE/LP VALVE/STBY	3WF	M41
121VU	APU/FUEL/LP VALVE/CTL	1QF	M40
121VU	APU/FUEL/LP VALVE/SPLY	2QF	M39
121VU	APU/FUEL/PUMP/CTL	3QC	M38
** ON A/C NOT FOR ALL
121VU	APU/FUEL/BLOW OFF/CTL	1QC	P38

4. Procedure
Subtask 49-00-00-710-065-A ** ON A/C NOT FOR ALL

A. APU Performance Test
(1) Read the LAST LEG REPORT of the Electronic Control Box (ECB) and make sure that there is no fault available.
(2) Do the self-test of the ECB (Ref. AMM TASK 49-00-00-710-009). Make sure that no maintenance message is shown.
(3) Start and operate the APU (Ref. AMM TASK 49-00-00-860-008).
(4) Activate the MES mode.

NOTE: The aircraft configuration for the MES mode on one engine is as follows:

APU BLEED pushbutton switch in the ON position
Dry-motoring of one engine.

(5) Do the steps that follow to make sure that the APU operates in the MES mode:
(a) On the APU system page of the lower ECAM DU make sure that the APU EGT increases.
(b) Get access to the parameter call-up menus (Ref. AMM TASK 31-36-00-740-008).
(c) Enter the ALPHA CALL-UP ASN for APU Serial Number.
(d) Make sure that the value shown for ASN is the same as the Serial Number of the APU installed.
(e) Enter the ALPHA CALL-UP for APU ADW.

NOTE: When you enter the ALPHA CALL-UP for ADW the APU operating status is shown in hexadecimal codes.
ADW ALPHA CALL-UP for SAGEM FDIMU = ADW1
ADW ALPHA CALL-UP for TELEDYNE FDIMU = ADW1ALL1

Make sure that bits 11 and 21 are equal to 1.

1 If bit 11 is equal to 1, the load valve is open.
2 If bit 21 is equal to 1, the ECB operates in MES mode.
(f) Enter the ALPHA CALL-UP IGV for APU IGV position.
(g) Make sure that the IGV position is between 92 and 97 deg.
(h) On the ECB APU parameter list, make sure that bits 12 "STRT VLV IN" and 13 "MES SW IN" of parameter 07A.1.274.01 are equal to 1.
(6) Stop the APU (Ref. AMM TASK 49-00-00-860-009).

5. Close-up
Subtask 49-00-00-860-197-A ** ON A/C NOT FOR ALL

A. Aircraft Maintenance Configuration
(1) Do the EIS stop procedure
(Ref. AMM TASK 31-60-00-860-002).
(2) De-energize the aircraft electrical circuits
(Ref. AMM TASK 24-41-00-862-002).

[Rev.10 from 2021] 2026.04.01 01:26:03 UTC