Pack 1 Electrical Component with Short Circuit (AIR PACK 1 REGUL FAULT)

TASK 21-61-00-810-820-A
Pack 1 Electrical Component with Short Circuit (AIR PACK 1 REGUL FAULT)

1. Possible Causes

FLOW CTL UNIT - PACK 1 [23HB]
P1 FLOW SENSOR [10HB]
SENSOR-DELTA P, PACK 1 [23HB2]
P1 RAM AIR IN ACTUATOR [8HH]
P1 CONTROLLER [7HH]
CONT-AIR COND SYSTEM 1 [47HH]
SENSOR-WATER EXTRACTOR TEMPERATURE [11HH]
VALVE-TURBINE BYPASS [10HH]
SENSOR-COMPRESSOR TEMPERATURE [12HH]
P1 FLOW CTL VALVE [11HB]
P1 PRESS INL SENSOR [16HH]
wiring
SENSOR-PRESS, PACK 1 INLET [23HB1]
SDAC
TEMP SENSOR LH MIXER [24HK]

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

REFERENCE	QTY	DESIGNATION
No specific	AR	WATER - SOAPY SOLUTION

B. Referenced Information

REFERENCE	DESIGNATION
AMM 12-33-21-618-001	Pre-conditioning through the LP Ground Connection
ASM 215101
ASM 215102
AMM 21-51-11-000-001	Removal of the Differential Pressure Sensor
AMM 21-51-11-400-001	Installation of the Differential Pressure Sensor
AMM 21-51-13-000-001	Removal of the Pack-Inlet Pressure Sensor
AMM 21-51-13-400-001	Installation of the Pack-Inlet Pressure Sensor
AMM 21-51-51-000-001	Removal of the Pack Flow-Control Valve/ Pack Flow-Control Unit
AMM 21-51-51-400-001	Installation of the Pack Flow-Control Valve/ Pack Flow-Control Unit
AMM 21-61-00-710-001	Operational Test of the Pack Temperature-Control System
AWM 216101
ASM 216102
AWM 216102
ASM 216103
AWM 216103
ASM 216104
AWM 216104
AWM 216109
AMM 21-61-11-000-001	Removal of the Compressor Outlet - Temperature Sensor
AMM 21-61-11-400-001	Installation of the Compressor Outlet - Temperature Sensor
AMM 21-61-13-000-001	Removal of the Water-Extractor Temperature Sensors
AMM 21-61-13-400-001	Installation of the Water-Extractor Temperature Sensors
AMM 21-61-16-000-001	Removal of the Pack-Inlet Pressure Sensor
AMM 21-61-16-400-002	Installation of the Pack-Inlet Pressure Sensor
AMM 21-61-34-000-001	Removal of the Pack Controller
AMM 21-61-34-000-002	Removal of the Air-Conditioning System Controller
AMM 21-61-34-400-001	Installation of the Pack Controller
AMM 21-61-34-400-002	Installation of the Air-Conditioning System Controller
AMM 21-61-51-000-001	Removal of the Air-Inlet Flap Actuator
AMM 21-61-51-400-001	Installation of the Air-Inlet Flap Actuator 8HH and 28HH
AMM 21-61-53-000-001	Removal of the Turbine Bypass Valve
AMM 21-61-53-400-001	Installation of the Turbine Bypass Valve
AMM 21-63-16-000-001	Removal of the Mixer Temperature Sensor
AMM 21-63-16-400-001	Installation of the Mixer Temperature Sensor
FCV Sensor Plate Inspection Area ** ON A/C NOT FOR ALL

3. Fault Confirmation
Subtask 21-61-00-865-050-A

A. Open this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	AIR COND/PACK TEMP/CTL SYS1/1/115VAC	1HH	X22
122VU	AIR COND/PACK TEMP CTL SYS2/1/115VAC	2HH	Y18

Subtask 21-61-00-865-051-A

B. Close this(these) circuit breaker(s):

PANEL	DESIGNATION	FIN	LOCATION
** ON A/C NOT FOR ALL
122VU	AIR COND/PACK TEMP/CTL SYS1/1/115VAC	1HH	X22
122VU	AIR COND/PACK TEMP CTL SYS2/1/115VAC	2HH	Y18

Subtask 21-61-00-710-088-A ** ON A/C NOT FOR ALL

C. Test
(1) Do a read out of the post flight report and do the operational test of the pack-temperature control system AMM 21-61-00-710-001.

NOTE: If the test finds a fault the PC gives a fault code for shop maintenance and also the related CFDS message(s) (refer to chapter 21-63-00 page block 301).

Subtask 21-61-00-710-088-B ** ON A/C NOT FOR ALL

C. Test

FCV Sensor Plate Inspection Area ** ON A/C NOT FOR ALL

(1) Do a read out of the post flight report and do the operational test of the pack-temperature control system AMM 21-61-00-710-001.
(2) Perform a leak check at the FCV Sensor plate:

NOTE: This procedure is only applicable for FCV P/N 1806A0000-02, 1806A0000-02 Amdt A, 1806B0000-01, 1806B0000-01 Amdt A, 1806B0000-01 Amdt AB, 1806B0000-01 Amdt B and 1806B0000-02.

(a) On the AIR COND panel 30VU:

make sure that the PACK pushbutton switch is in the OFF position.

(b) Do the pre-conditioning through the HP ground connector or with the APU AMM 12-33-21-618-001.
(c) Apply a WATER - SOAPY SOLUTION to the connections behind the sensor plate to search for a leak.

4. Fault Isolation
Subtask 21-61-00-810-272-B ** ON A/C NOT FOR ALL

A. If a leakage is found:

replace the FLOW CTL UNIT - PACK 1 [23HB] , AMM 21-51-51-000-001 and AMM 21-51-51-400-001.

Subtask 21-61-00-810-112-A ** ON A/C NOT FOR ALL

B. * If the post flight report gives the warning AIR PACK 1 REGUL FAULT without a maintenance message and,
* no AIR PACK 1 REGUL FAULT warning shows on the ECAM upper DU and,
* no maintenance message shows:

replace the P1 FLOW SENSOR [10HB] AMM 21-51-11-000-001 and AMM 21-51-11-400-001.
** If the post flight report gives the warning AIR PACK 1 REGUL FAULT and,
** the ECAM upper DU shows the warning AIR PACK 1 REGUL FAULT or,
*** If the post flight report gives the warning AIR PACK 1 REGUL FAULT with,
*** the maintenance message NO DATA FROM P1 CONT and,
*** the operational test of the pack-temperature control system gives the maintenance message NO TEST RECEPTION FROM P1 CONT:
do the work steps which follow.

NOTE: Additional Information
For wiring and pin identification used in this procedure:
ASM 215101,
ASM 216102,
ASM 216104 and,
AWM 216109.
For disconnection/reconnection of electrical connectors refer to the applicable work step AMM TASK reference in the applicable paras. 4. B, C, D and E.

Subtask 21-61-00-810-181-B ** ON A/C NOT FOR ALL

C. Check for short circuit at the P1 RAM AIR IN ACTUATOR [8HH] 115VAC supply lines
(1) Remove the P1 CONTROLLER [7HH] ,
AMM 21-61-34-000-001:
(2) Disconnect the electrical connector (8HH/A) from the P1 RAM AIR IN ACTUATOR [8HH] :

do a check for a short circuit between,
* pins J and N and,
* GND and pins J and N.
if there is a short circuit repair the related wiring between,
* connector (8HH/A) pin J and PC connector (7HH/AB) pin 15A,
* connector (8HH/A) pin N and PC connector (7HH/AB) pin 14B.
if there is no short circuit in the wiring replace the P1 RAM AIR IN ACTUATOR [8HH] ,
AMM 21-61-51-000-001 and,
AMM 21-61-51-400-001.
install the P1 CONTROLLER [7HH]
AMM 21-61-34-400-001.
connect the electrical connector (8HH/A) to the P1 RAM AIR IN ACTUATOR [8HH] .

Subtask 21-61-00-810-182-A ** ON A/C NOT FOR ALL

D. If the fault continues:
(1) Swap the PC 1 (7HH) and the PC 2 (27HH)
AMM 21-61-34-000-001 and,
AMM 21-61-34-400-001.
(a) If the fault moves with the PC 1:

swap back the PC 1 (7HH) and the PC 2 (27HH)
AMM 21-61-34-000-001 and,
AMM 21-61-34-400-001.
replace the P1 CONTROLLER [7HH]
AMM 21-61-34-000-001 and,
AMM 21-61-34-400-001.

(2) If the fault does not move with the PC 1:

swap back the PC 1 (7HH) and the PC 2 (27HH)
AMM 21-61-34-000-001 and,
AMM 21-61-34-400-001.

Subtask 21-61-00-810-183-B ** ON A/C NOT FOR ALL

E. If the fault continues:
(1) Disconnect the electrical connector (11HH/A) from the SENSOR-WATER EXTRACTOR TEMPERATURE [11HH] ,

make sure that the electrical connector is clean and in the correct condition,
at the electrical connector (11HH/A) do a check for voltage between,
* pins E and F.

(a) If the voltage is between 9.6VDC and 10.4VDC:

replace the SENSOR-WATER EXTRACTOR TEMPERATURE [11HH]
AMM 21-61-13-000-001 and,
AMM 21-61-13-400-001.

(b) If the voltage is not between 9.6VDC and 10.4VDC:

disconnect the electrical connector (8HH/A) from the P1 RAM AIR IN ACTUATOR [8HH] ,
make sure that the electrical connector is clean and in the correct condition,
at the electrical connector (11HH/A) do a check for voltage again.

1 If the voltage is between 9.6VDC and 10.4VDC:

replace the P1 RAM AIR IN ACTUATOR [8HH]
AMM 21-61-51-000-001 and,
AMM 21-61-51-400-001.
connect the electrical connector (11HH/A).

2 If the voltage is not between 9.6VDC and 10.4VDC:

connect the electrical connector (8HH/A),
repeat para. 4.E.(1).(b) for,
* connector (10HH/A) and the VALVE-TURBINE BYPASS [10HH]
AMM 21-61-53-000-001 and,
AMM 21-61-53-400-001,
* connector (12HH/A) and the SENSOR-COMPRESSOR TEMPERATURE [12HH]
AMM 21-61-11-000-001 and,
AMM 21-61-11-400-001,
* connector (11HB/A) and the P1 FLOW CTL VALVE [11HB]
AMM 21-51-51-000-001 and,
AMM 21-51-51-400-001.

Subtask 21-61-00-810-184-A ** ON A/C NOT FOR ALL

F. If the fault continues:
(1) disconnect the electrical connector (7559VC/A) from the P1 PRESS INL SENSOR [16HH] .

make sure that the electrical connector is clean and in the correct condition.
at the electrical connector (7559VC) do a check for 15VDC from pack controller primary channel between,
* pins A and C (+15VDC) and,
* D and C (-15VDC).

(a) If the voltage is correct:

replace the P1 PRESS INL SENSOR [16HH]
AMM 21-61-16-000-001 and,
AMM 21-61-16-400-002.
connect the electrical connector (7559VC/A).

(2) If the fault continues:

Remove the P1 CONTROLLER [7HH]
AMM 21-61-34-000-001,
disconnect the electrical connector (11HH/A) from the SENSOR-WATER EXTRACTOR TEMPERATURE [11HH] ,
at the electrical connector (11HH/A) do a check for a short circuit between,
* pins E and F and,
* GND and pins E and F.

(a) If there is no short circuit connect the electrical connector (11HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (11HH/A) pin E and PC 1 connector (7HH/AA) pin 14A,
* connector (11HH/A) pin F and PC 1 connector (7HH/AA) pin 14B.

connect the electrical connector (11HH/A).

(3) If the fault continues:

disconnect the electrical connector (8HH/A) from the P1 RAM AIR IN ACTUATOR [8HH] ,
at the electrical connector (8HH/A) do a check for a short circuit between,
* pins A and B, A and C, B and C and,
* GND and pins A, B and C.

(a) If there is no short circuit connect the electrical connector (8HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (8HH/A) pin A and PC 1 connector (7HH/AA) pin 11D,
* connector (8HH/A) pin B and PC 1 connector (7HH/AA) pin 12A,
* connector (8HH/A) pin C and PC 1 connector (7HH/AA) pin 12B:

connect the electrical connector (8HH/A).

Subtask 21-61-00-810-112-B ** ON A/C NOT FOR ALL

G. * If the post flight report gives the warning AIR PACK 1 REGUL FAULT without a maintenance message and,
* no AIR PACK 1 REGUL FAULT warning shows on the ECAM upper DU and,
* no maintenance message shows:

replace the SENSOR-DELTA P, PACK 1 [23HB2] ,
AMM 21-51-11-000-001 and AMM 21-51-11-400-001 (less probable cause for this failure).

(1) If the fault continues:

replace the FLOW CTL UNIT - PACK 1 [23HB] ,
AMM 21-51-51-000-001 and AMM 21-51-51-400-001.
no further action is necessary.
** If the post flight report gives the warning AIR PACK 1 REGUL FAULT and,
** the ECAM upper DU shows the warning AIR PACK 1 REGUL FAULT or:
do the work steps which follow.

NOTE: Additional Information
For wiring and pin identification used in this procedure:
ASM 215102,
ASM 216103,
ASM 216104,
AWM 216101,
AWM 216102,
AWM 216103and,
AWM 216104.
For disconnection/reconnection of electrical connectors refer to the applicable work step AMM TASK reference in the applicable paras. 4. B, C, D and E.

Subtask 21-61-00-810-181-C ** ON A/C NOT FOR ALL

H. Check for short circuit at the P1 RAM AIR IN ACTUATOR [8HH] 115VAC supply lines
(1) Remove the CONT-AIR COND SYSTEM 1 [47HH] ,
AMM 21-61-34-000-002:
(2) Disconnect the electrical connector (8HH/A) from the P1 RAM AIR IN ACTUATOR [8HH] :

do a check for a short circuit between,
* pins J and K and,
* GND and pins J and K.
if there is a short circuit repair the related wiring between,
* connector (8HH/A) pin J and ACSC1 connector (47HH/AB) pin 15J,
* connector (8HH/A) pin K and ACSC1 connector (47HH/AB) pin 15K.
if there is no short circuit in the wiring replace the P1 RAM AIR IN ACTUATOR [8HH] ,
AMM 21-61-51-000-001 and,
AMM 21-61-51-400-001.
install the CONT-AIR COND SYSTEM 1 [47HH]
AMM 21-61-34-400-002.
connect the electrical connector (8HH/A) to the P1 RAM AIR IN ACTUATOR [8HH] .

Subtask 21-61-00-810-182-B ** ON A/C NOT FOR ALL

I. If the fault continues:
(1) Swap the ACSC1 (47HH) and the ACSC2 (57HH)
AMM 21-61-34-000-002 and,
AMM 21-61-34-400-002.
(a) If the fault moves with the ACSC1:

swap back the ACSC1 (47HH) and the ACSC2 (57HH)
AMM 21-61-34-000-002 and,
AMM 21-61-34-400-002.
replace the CONT-AIR COND SYSTEM 1 [47HH]
AMM 21-61-34-000-002 and,
AMM 21-61-34-400-002.

(2) If the fault does not move with the ACSC1:

swap back the ACSC1 (47HH) and the ACSC2 (57HH)
AMM 21-61-34-000-002 and,
AMM 21-61-34-400-002.

Subtask 21-61-00-810-183-D ** ON A/C NOT FOR ALL

J. If the fault continues:
(1) Disconnect the electrical connector (11HH/A) from the SENSOR-WATER EXTRACTOR TEMPERATURE [11HH] ,

make sure that the electrical connector is clean and in the correct condition,
at the electrical connector (11HH/A) do a check for voltage between,
* pins E and F.

(a) If the voltage is between 9.1VDC and 9.9VDC:

replace the SENSOR-WATER EXTRACTOR TEMPERATURE [11HH]
AMM 21-61-13-000-001 and,
AMM 21-61-13-400-001.

(b) If the voltage is not between 9.1VDC and 9.9VDC:

disconnect the electrical connector (8HH/A) from the P1 RAM AIR IN ACTUATOR [8HH] ,
make sure that the electrical connector is clean and in the correct condition,
at the electrical connector (11HH/A) do a check for voltage again.

1 If the voltage is between 9.1VDC and 9.9VDC:

replace the P1 RAM AIR IN ACTUATOR [8HH]
AMM 21-61-51-000-001 and,
AMM 21-61-51-400-001.
connect the electrical connector (11HH/A).

2 If the voltage is not between 9.1VDC and 9.9VDC:

connect the electrical connector (8HH/A),
repeat para. 4.E.(1).(b) for,
* connector (10HH/A) and the VALVE-TURBINE BYPASS [10HH]
AMM 21-61-53-000-001 and,
AMM 21-61-53-400-001,
* connector (12HH/A) and the SENSOR-COMPRESSOR TEMPERATURE [12HH]
AMM 21-61-11-000-001 and,
AMM 21-61-11-400-001,
* connector (23HB/A) and the FLOW CTL UNIT - PACK 1 [23HB]
AMM 21-51-51-000-001 and,
AMM 21-51-51-400-001.

Subtask 21-61-00-810-184-B ** ON A/C NOT FOR ALL

K. If the fault continues:
(1) disconnect the electrical connector (23HB1/A) from the SENSOR-PRESS, PACK 1 INLET [23HB1] .

make sure that the electrical connector is clean and in the correct condition.
at the electrical connector (23HB1/A) do a check for 15VDC from ACSC primary channel between,
* pins A and C (+15VDC)

(a) If the voltage is correct:

replace the SENSOR-PRESS, PACK 1 INLET [23HB1]
AMM 21-51-13-000-001 and,
AMM 21-51-13-400-001.
connect the electrical connector (23HB1/A).

(2) If the fault continues:

Remove the CONT-AIR COND SYSTEM 1 [47HH]
AMM 21-61-34-000-002,
disconnect the electrical connector (11HH/A) from the SENSOR-WATER EXTRACTOR TEMPERATURE [11HH] ,
at the electrical connector (11HH/A) do a check for a short circuit between,
* pins C and D and,
* GND and pins C and D.

(a) If there is no short circuit connect the electrical connector (11HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (11HH/A) pin C and ACSC1 connector (47HH/AA) pin 4A,
* connector (11HH/A) pin D and ACSC1 connector (47HH/AA) pin 4B.

connect the electrical connector (11HH/A).

(3) If the fault continues:

disconnect the electrical connector (8HH/A) from the P1 RAM AIR IN ACTUATOR [8HH] ,
at the electrical connector (8HH/A) do a check for a short circuit between,
* pins A and B, A and C, B and C and,
* GND and pins A, B and C.

(a) If there is no short circuit connect the electrical connector (8HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (8HH/A) pin A and ACSC1 connector (47HH/AA) pin 14B,
* connector (8HH/A) pin B and ACSC1 connector (47HH/AA) pin 14A,
* connector (8HH/A) pin C and ACSC1 connector (47HH/AA) pin 14C:

connect the electrical connector (8HH/A).

Subtask 21-61-00-810-193-B ** ON A/C NOT FOR ALL

L. If the fault continues:
(1) Disconnect the electrical connector (10HH/A) from the VALVE-TURBINE BYPASS [10HH] ,

at the electrical connector (10HH/A) do a check for a short circuit between,
* pins U and J, U and K, U and L, J and K, J and L, K and L, C and D and,
* GND and pins U, J, K, L and C.

(a) If there is no short circuit connect the electrical connector (10HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (10HH/A) pin U and PC 1 connector (7HH/AA) pin 2A,
* connector (10HH/A) pin J and PC 1 connector (7HH/AA) pin 2B,
* connector (10HH/A) pin K and PC 1 connector (7HH/AA) pin 2C,
* connector (10HH/A) pin L and PC 1 connector (7HH/AA) pin 2D,
* connector (10HH/A) pin C and PC 1 connector (7HH/AB) pin 5B.

connect the electrical connector (10HH/A).

Subtask 21-61-00-810-186-A ** ON A/C NOT FOR ALL

M. If the fault continues:
(1) Disconnect the electrical connector (12HH/A) from the SENSOR-COMPRESSOR TEMPERATURE [12HH] ,

at the electrical connector (12HH/A) do a check for a short circuit between,
* pins A and B, A and C, B and C and,
* GND and pins A, B and C.

(a) If there is no short circuit connect the electrical connector (12HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (12HH/A) pin A and PC 1 connector (7HH/AA) pin 15A,
* connector (12HH/A) pin B and PC 1 connector (7HH/AA) pin 14D,
* connector (12HH/A) pin C and PC 1 connector (7HH/AA) pin 14C.

connect the electrical connector (12HH/A).

(2) If the fault continues:

disconnect the electrical connector (7559VC/A),
at the connector (7559VC) do a check for a short circuit between,
* pins A and B, A and C, A and D, B and C, B and D, C and D and,
* GND and pins A, B, C and D.

(a) If there is no short circuit connect the electrical connector (7559VC/A).
(b) If there is a short circuit repair the related wiring between,
* connector (7559VC) pin A and PC 1 connector (7HH/AB) pin 15C,
* connector (7559VC) pin D and PC 1 connector (7HH/AB) pin 15D,
* connector (7559VC) pin C and PC 1 connector (7HH/AA) pin 10C,
* connector (7559VC) pin B and PC 1 connector (7HH/AA) pin 10D.

connect the electrical connector (7559VC/A).

(3) If the fault continues:

disconnect the electrical connector (11HB/A) from the P1 FLOW CTL VALVE [11HB] ,
at the electrical connector (11HB/A) do a check for a short circuit between,
* pins J and K, J and L, K and L and,
* GND and pins J, K and L.

(a) If there is no short circuit connect the electrical connector (11HB/A).
(b) If there is a short circuit repair the related wiring between,
* connector (11HB/A) pin J and PC 1 connector (7HH/AA) pin 11C,
* connector (11HB/A) pin K and PC 1 connector (7HH/AA) pin 11B,
* connector (11HB/A) pin L and PC 1 connector (7HH/AA) pin 11A.

connect the electrical connector (11HB/A).

(4) Install the P1 CONTROLLER [7HH] ,
AMM 21-61-34-400-001.
(5) If the fault continues:
(a) Swap the SDAC's (1WV1 and 1WV2). (Ref.AMM TASK 31-55-34-401)
(b) If this action has solved the problem:

replace the SDAC which formerly was SDAC1.

Subtask 21-61-00-810-193-C ** ON A/C NOT FOR ALL

N. If the fault continues:
(1) Disconnect the electrical connector (10HH/A) from the VALVE-TURBINE BYPASS [10HH] ,

at the electrical connector (10HH/A) do a check for a short circuit between,
* pins U and J, U and K, U and L, J and K, J and L, K and L, C and D and,
* GND and pins U, J, K, L and C.

(a) If there is no short circuit connect the electrical connector (10HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (10HH/A) pin U and ACSC1 connector (47HH/AA) pin 15D,
* connector (10HH/A) pin J and ACSC1 connector (47HH/AA) pin 15A,
* connector (10HH/A) pin K and ACSC1 connector (47HH/AA) pin 15B,
* connector (10HH/A) pin L and ACSC1 connector (47HH/AA) pin 15C,
* connector (10HH/A) pin C and ACSC1 connector (47HH/AB) pin 15E.

connect the electrical connector (10HH/A).

Subtask 21-61-00-810-186-B ** ON A/C NOT FOR ALL

O. If the fault continues:
(1) Disconnect the electrical connector (12HH/A) from the SENSOR-COMPRESSOR TEMPERATURE [12HH] ,

at the electrical connector (12HH/A) do a check for a short circuit between,
* pins B and C, B and D, C and D and,
* GND and pins B, C and D.

(a) If there is no short circuit connect the electrical connector (12HH/A).
(b) If there is a short circuit repair the related wiring between,
* connector (12HH/A) pin B and ACSC1 connector (47HH/AA) pin 6B,
* connector (12HH/A) pin C and ACSC1 connector (47HH/AA) pin 6C,
* connector (12HH/A) pin D and ACSC1 connector (47HH/AA) pin 6A,

connect the electrical connector (12HH/A).

(2) If the fault continues:

disconnect the electrical connector (23HB1/A),
at the connector (23HB1/A) do a check for a short circuit between,
* pins A and B, A and C, B and C and,
* GND and pins A, B and C.

(a) If there is no short circuit connect the electrical connector (23HB1/A).
(b) If there is a short circuit repair the related wiring between,
* connector (23HB1/A) pin A and ACSC1 connector (47HH/AB) pin 10H,
* connector (23HB1/A) pin B and ACSC1 connector (47HH/AB) pin 10K,
* connector (23HB1/A) pin C and ACSC1 connector (47HH/AA) pin 10J.

connect the electrical connector (23HB1/A).

(3) Install the CONT-AIR COND SYSTEM 1 [47HH] ,
AMM 21-61-34-400-002.
(4) If the fault continues:

replace the TEMP SENSOR LH MIXER [24HK]
AMM 21-63-16-000-001 and,
AMM 21-63-16-400-001.

(5) If the fault continues:
(a) Swap the SDAC's (1WV1 and 1WV2). (Ref.AMM TASK 31-55-34-401)
(b) If this action has solved the problem:

replace the SDAC which formerly was SDAC1.

Subtask 21-61-00-710-089-A

P. Do the test as given in the Para. 3.A.

5. Close-up
Subtask 21-61-00-860-069-A

A. Put the aircraft back to its initial configuration.

[Rev.8 from Aug 2018] 2026.04.04 04:24:54 UTC