W DOC AIRBUS | TSM A320F

Failure of the GLC 2 Control Circuit

TASK 24-20-00-810-893-A
Failure of the GLC 2 Control Circuit

1. Possible Causes
2. Job Set-up Information
 A. Fixtures, Tools, Test and Support Equipment
REFERENCE
QTY
DESIGNATION
No specific
AR
SAFETY CLIP - CIRCUIT BREAKER
 B. Referenced Information
REFERENCE
DESIGNATION
ASM 242203
AMM 24-22-34-000-001
Removal of the GCU-1(2)
AMM 24-22-34-400-001
Installation of the GCU-1(2)
AMM 24-22-55-000-001
Removal of the Contactors
AMM 24-22-55-400-002
Installation of the Contactors
AMM 24-41-00-740-002
Operational Check of the GAPCU via the CFDS
AMM 24-41-00-861-002
Energize the Aircraft Electrical Circuits from the External Power
AMM 24-41-00-862-002
De-energize the Aircraft Electrical Circuits Supplied from the External Power
AMM 31-60-00-860-001
EIS Start Procedure
AMM 31-60-00-860-002
EIS Stop Procedure
AMM 71-00-00-710-003
Engine Automatic Start
AMM 71-00-00-710-028
Engine Shutdown
AMM 71-00-00-860-814
Shutdown of the Engine
AMM 71-00-00-860-823
Start the Engine (Normal Automatic Start)
3. Fault Confirmation
Subtask 24-20-00-869-091-A ** ON A/C NOT FOR ALL
A. Test
Not applicable.
NOTE: As the GEN 2 was set to OFF because of a true failure, the fault confirmation is not necessary.
4. Fault Isolation
Subtask 24-20-00-810-158-A ** ON A/C NOT FOR ALL
A. If the fault symptom is identified by the CFDS message GLC AUX RLY (4XU2)/ GLC2 (9XU2)/ GCU2 (1XU2) and the upper ECAM-DU warning GEN 2 FAULT:
   (1) If the CFDS message comes into view associated with fault code 19 (GLC CONTROL CKT keyword):
   (2) If the CFDS message comes into view associated with fault codes 180 (PR SSR OC ACTIVE keyword) or 183 (GLC CONTROL CKT keyword):
  • Continue the trouble shooting procedure.
Subtask 24-20-00-865-068-A ** ON A/C NOT FOR ALL
B. Open, safety and tag this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C NOT FOR ALL
122VUELEC/GEN2/OFF/BTC1 SPLY15XUT29
Subtask 24-20-00-810-252-A ** ON A/C NOT FOR ALL
C. Do this procedure:
   (1) Make sure that the aircraft is de-energized AMM 24-41-00-862-002.
   (2) Remove GCU2 AMM 24-22-34-000-001.
   (3) Connect pin AC/4 (28VDC) and pin AB/10J of GCU 2 (1XU2) together.
   (4) Remove the GLC2 auxiliary control-relay (4XU2).
   (5) On ELEC panel 35VU:
  • Push the BAT 1 pushbutton switch, and
  • Make sure that GEN2 pushbutton switch (3XU2) is pushed.
   (6) Do a check of 28VDC between pin A/X1 of the GLC2 auxiliary control-relay (4XU2) and the ground.
     (a) If there is no 28VDC:
  • Replace P/BSW-ELEC/GEN 2 [3XU2] .
       1 If the fault continues:
  • Do a check for continuity and repair the wiring ASM 242203 between:
    . Pin AB/10J of GCU2 (1XU2) and pin A/C3 of the GEN2 pushbutton switch (3XU2)
    . Pin A/C1 of the GEN2 pushbutton switch (3XU2) and pin A/X1 of the GLC 2 auxiliary control-relay (4XU2)
    . Pin A/X2 of the GLC2 auxiliary control-relay (4XU2) and the ground.
   (7) Do a check of the voltage between pin A/D2 of the GLC2 auxiliary control-relay (4XU2) and the ground.
     (a) If there is no voltage:
  • Disconnect electrical connector B of BTC2 (11XU2) AMM 24-22-55-000-001 and do a check of the voltage on pin B/10:
       1 If there is voltage:
         a If the fault continues:
  • Do a check and repair the wiring ASM 242203 between pin B/12 of BTC2 and pin A/D2 of the GLC2 auxiliary control-relay (4XU2).
       2 If there is no voltage:
  • Replace diode module 2422VD.
         a If the fault continues:
  • Do a check and repair the wiring ASM 242203 between:
    . Pin B/10 of BTC2 and pin A/8 of diode module 2422VD
    . Pin AB/10J of GCU2 (1XU2) and pin A/23 of diode module 2422VD.
     (b) If there is voltage:
       1 Release the BAT 1 pushbutton switch.
       2 Connect pin A/D2 and pin A/D1 of the GLC2 auxiliary control-relay (4XU2) together.
       3 Disconnect electrical connector B of GLC2.
       4 Do a check for continuity between pin B/5 of GLC2 (9XU2) and the ground.
         a If there is no continuity:
  • Repair the wiring.
   (8) Push the BAT 1 pushbutton switch.
   (9) On electrical connector B of GLC2 (9XU2), do a check of the voltage between pin B/3 and the ground.
     (a) If there is voltage:
     (b) If there is no voltage:
  • Do a check and repair the wiring ASM 242203 between pin B/3 of GLC2 (9XU2) and pin A/D1 of the GLC 2 auxiliary control-relay (4XU2).
   (10) Release the BAT 1 pushbutton switch.
   (11) Remove the connection between pin A/D2 and pin A/D1 of the GLC2 auxiliary control-relay (4XU2).
   (12) Install the GLC2 auxiliary control-relay (4XU2).
   (13) Push the BAT 1 pushbutton switch.
   (14) Push and release the GEN2 pushbutton switch many times. If you cannot hear the contacts that close/open on GLC2 (9XU2):
     (a) Replace the RELAY-GLC 2 AUX CTL [4XU2] .
   (15) Release the BAT 1 pushbutton switch.
   (16) Remove the connection between pin AC/4 (28VDC) and pin AB/10J of GCU2 (1XU2).
   (17) Install GCU-2 [1XU2] AMM 24-22-34-400-001.
Subtask 24-20-00-865-072-A ** ON A/C NOT FOR ALL
D. Remove the safety clip(s) and the tag(s) and close this(these) circuit breaker(s):
PANELDESIGNATIONFINLOCATION
** ON A/C NOT FOR ALL
122VUELEC/GEN2/OFF/BTC1 SPLY15XUT29
Subtask 24-20-00-710-136-C ** ON A/C NOT FOR ALL
E. Do this operational test to make sure that the system operates correctly.
   (1) Aircraft Maintenance Configuration
     (a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
     (b) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only)
AMM 31-60-00-860-001.
   (2) In the cockpit, on the ELEC panel 35VU:
  • Push, release and push again the GEN 2 pushbutton switch (3XU2).
   (3) Do the BITE test of the GAPCU AMM 24-41-00-740-002.
   (4) Start engine 2 AMM 71-00-00-860-823.
   (5) Do this test:
ACTION
RESULT
On the ECAM control panel:
  • Push the ELEC key to get the ELEC page.
On the lower ECAM DU:
  • The correct electrical parameters of GEN 2 are shown and GEN 2 supplies the AC2 busbar.
Subtask 24-20-00-710-136-G ** ON A/C NOT FOR ALL
E. Do this operational test to make sure that the system operates correctly.
   (1) Aircraft Maintenance Configuration
     (a) Energize the aircraft electrical circuits
AMM 24-41-00-861-002.
     (b) Do the EIS start procedure (Upper ECAM DU and lower ECAM DU only)
AMM 31-60-00-860-001.
   (2) On the ELEC panel 35VU:
  • push, release and push again the GEN 2 pushbutton switch (3XU2).
   (3) Do the operational test of the GAPCU AMM 24-41-00-740-002.
   (4) Start the engine 2 AMM 71-00-00-710-003.
   (5) Do this test:
ACTION
RESULT
On the ECAM control panel:
  • get the ELEC page.
On the lower ECAM DU:
  • the correct electrical parameters of the GEN 2 are shown and the AC2 busbar is supplied by the GEN 2.
5. Close-up
Subtask 24-20-00-860-161-C ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Stop engine 2 AMM 71-00-00-860-814.
   (2) Do the EIS stop procedure
AMM 31-60-00-860-002.
   (3) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
   (4) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.
Subtask 24-20-00-860-161-G ** ON A/C NOT FOR ALL
A. Put the aircraft back to its initial configuration.
   (1) Stop the engine 2 AMM 71-00-00-710-028.
   (2) Do the EIS stop procedure
AMM 31-60-00-860-002.
   (3) On the ECAM control panel, set the UPPER DISPLAY and LOWER DISPLAY potentiometers to OFF.
   (4) De-energize the aircraft electrical circuits
AMM 24-41-00-862-002.
[Rev.8 from Aug 2018] 2026.04.04 04:26:19 UTC
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