W DOC AIRBUS | TSM A320F

Failure of the IDG 2 Control Circuits or of its Wiring to the GCU 2

TASK 24-21-00-810-827-A
Failure of the IDG 2 Control Circuits or of its Wiring to the GCU 2

1. Possible Causes
2. Job Set-up Information
 A. Referenced Information
REFERENCE
DESIGNATION
ASM 242101
AMM 24-21-51-000-040
Removal of the Integrated Drive Generator - IDG 1(2)
AMM 24-21-51-000-803
Removal of the Integrated Drive Generator - IDG 1(2)
AMM 24-21-51-400-040
Installation of the Integrated Drive Generator - IDG 1(2)
AMM 24-21-51-400-803
Installation of the Integrated Drive Generator - IDG 1(2)
ASM 242201
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 24-41-00-740-002
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)
F Illustration of the IDG Servovalve Resistance Versus Temperature
3. Fault Confirmation
Subtask 24-21-00-869-055-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
CAUTION: BEFORE YOU START THE CHECK OF IDG WIRING THAT INCLUDES CONNECTORS, EXAMINE EACH CONNECTOR TO MAKE SURE THAT THERE IS NO CONTAMINATION IN IT. IF YOU FIND CONTAMINATION, CLEAN THE CONNECTOR AND CONNECT IT AGAIN. IF THE FAILURE CONTINUES, DO THE TROUBLE SHOOTING PROCEDURE AS GIVEN BELOW.
Subtask 24-21-00-810-086-D ** ON A/C NOT FOR ALL
A. If the fault symptom is identified by the CFDS message IDG2 (E2-4000XU)/ GCU2 (1XU2) and the upper ECAM-DU warning GEN 2 FAULT:
   (1) If the CFDS messages comes into view associated with the fault code 117 (UF TRIP DEFAULT keyword):
  • Do the trouble shooting for all EEC messages that come into view with the CFDS message IDG2 (E2-4000XU)/ GCU2 (1XU2).
   (2) If there are no EEC messages, or if the fault continues after the trouble shooting for EEC messages:
     (a) If the fault continues:
   (3) If the CFDS messages comes into view associated with the fault code 251 (RECOG FREQ CTL keyword):
     (a) If the BITE test gives the message TEST FAILED:
  • Push the line key adjacent to the TEST FAILED message.
       1 If the maintenance message GCU2 (1XU2) comes into view:
     (b) If the BITE test gives the message TEST PASSED:
  • Do a check of the resistance of the IDG2 servo-valve speed-control between pins C/1 and C/2 ASM 242101.
       1 If the resistance values are out of the specified limits:
F Illustration of the IDG Servovalve Resistance Versus Temperature ** ON A/C NOT FOR ALL
       2 If the resistance values are in the specified limits:
F Illustration of the IDG Servovalve Resistance Versus Temperature ** ON A/C NOT FOR ALL
  • Do a check of the wiring of the servo-valve speed control ASM 242101 for a short to ground, a short circuit, an open circuit or a high resistance condition between:
    . Pin C/1 of the IDG2 and pin AB/11J of the GCU2
    . Pin C/2 of the IDG2 and pin AB/11H of the GCU2.

         a If the wiring is not correct:
  • Repair or replace as necessary.

         b If the wiring is correct:
         c If the fault continues:
   (4) If the CFDS messages comes into view associated with the fault code 198 (UNCONTROLED SD keyword):
  • Do an electrical resistance test of the IDG2 exciter field between pins B/11 and B/12 (8.4 ohm plus or minus 1.26 ohm) ASM 242201:
     (a) If the resistance values are out of the specified limits:
     (b) If the resistance values are in the specified limits:
  • Do an electrical resistance test of the IDG2 PMG stator ASM 242201 between:
    . Pins A/2 and A/10 (1 ohm plus or minus 0.15 ohm)
    . Pins A/2 and A/11 (1 ohm plus or minus 0.15 ohm)
    . Pins A/10 and A/11 (1 ohm plus or minus 0.15 ohm).
       1 If the resistance values are out of the specified limits:
         a If the resistance values are in the specified limits:
  • Do a check of the wiring of the PMG stator and exciter field ASM 242201 for a short to ground, a short circuit or an open circuit between:
    . Pin A/2 of the IDG2 and pin AC/10 of the GCU2
    . Pin A/10 of the IDG2 and pin AC/11 of the GCU2
    . Pin A/12 of the IDG2 and pin AC/9 of the GCU2
    . Pins AC/10, AC/11, AC/9 and AC/7 of the GCU2 (short to shield of the PMG stator)
    . Pin B/11 of the IDG2 and pin AC/12 of the GCU2
    . Pin B/12 of the IDG2 and pin AC/13 of the GCU2
    . Pins AC/12, AC/13 and pin AC/7 of the GCU2 (short to shield of the exciter field).

    * If the wiring is not correct:
    * - Repair it.

    * If the wiring is correct:
    * - Replace the GCU-2 [1XU2] AMM 24-22-34-000-001 and AMM 24-22-34-400-001.
Subtask 24-21-00-710-086-D ** ON A/C NOT FOR ALL
B. Test
   (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 operational check of the GAPCU via the CFDS 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 24-21-00-810-086-G ** ON A/C NOT FOR ALL
C. If the fault symptom is identified by the CFDS message IDG2 (E2-4000XU)/ GCU2 (1XU2) and the upper ECAM DU warning GEN 2 FAULT:
   (1) If the CFDS messages comes into view associated with the fault code 117 (UF TRIP DEFAUT keyword):
  • Do the trouble shooting for all ECU messages that come into view with the CFDS message IDG2 (E2-4000XU)/ GCU2 (1XU2).
     (a) If there are no ECU messages, or if the fault continues after the trouble shooting for ECU messages:
       1 If the fault continues:
   (2) If the CFDS messages comes into view associated with the fault code 251 (RECOG FREQ CTL keyword):
     (a) If the BITE test gives the message TEST FAILED:
  • Push the line key adjacent to the TEST FAILED message.
       1 If the maintenance message GCU2 (1XU2) comes into view:
     (b) If the BITE test gives the message TEST PASSED:
       1 For the IDG P/N 772181 or the IDG P/N 1706903 or the P/N 1708897:
  • Do a check of the resistance of the IDG 2 servo-valve speed-control between pins B/1 and B/2 ASM 242101.
         a If the resistance value is out of the specified limits given in:
F Illustration of the IDG Servovalve Resistance Versus Temperature ** ON A/C NOT FOR ALL
         b If the resistance value is in the specified limits given in:
F Illustration of the IDG Servovalve Resistance Versus Temperature ** ON A/C NOT FOR ALL
  • Do a check of the wiring of the servo-valve speed control ASM 242101 for a short to ground, a short circuit, an open circuit or a high resistance condition between:
    . Pin B/1 of the IDG 2 and pin B/11J of the GCU 2
    . Pin B/2 of the IDG 2 and pin B/11H of the GCU 2.

    * If the wiring is not correct:
    * - Repair or replace as necessary.

    * If the wiring is correct:
    * - Replace the engine 2 IDG [4000XU] AMM 24-21-51-000-040 and AMM 24-21-51-400-040.

    ** If the fault continues:
    ** - Replace the GCU-2 [1XU2] AMM 24-22-34-000-001 and AMM 24-22-34-400-001.
       2 For the IDG P/N 772292:
  • Do a check of the resistance of the IDG 2 servo-valve speed-control between pins A/2 and A/3 ASM 242101.
         a If the resistance value is out of the specified limits given in:
F Illustration of the IDG Servovalve Resistance Versus Temperature ** ON A/C NOT FOR ALL
         b If the resistance value is in the specified limits given in:
F Illustration of the IDG Servovalve Resistance Versus Temperature ** ON A/C NOT FOR ALL
  • Do a check of the wiring of the servo-valve speed control ASM 242101 for a short to ground, a short circuit, an open circuit or a high resistance condition between:
    . Pin A/2 of the IDG 2 and pin B/11J of the GCU 2
    . Pin A/3 of the IDG 2 and pin B/11H of the GCU 2.

    * If the wiring is not correct:
    * - Repair or replace as necessary.

    * If the wiring is correct:
    * - Replace the engine 2 IDG [4000XU] AMM 24-21-51-000-040 and AMM 24-21-51-400-040.

    ** If the fault continues:
    ** - Replace the GCU-2 [1XU2] AMM 24-22-34-000-001 and AMM 24-22-34-400-001.
       3 For the IDG P/N 740119 or the IDG P/N 766219:
         a If the fault continues:
   (3) If the CFDS messages comes into view associated with the fault code 198 (UNCONTROLED SD keyword):
     (a) For the IDG P/N 772181 or the IDG P/N 772292 or the IDG P/N 1706903 or the P/N 1708897:
  • Do an electrical resistance test of the IDG 2 exciter field between pins A/9 and A/10 (8.4 ohms plus or minus 0.84 ohms) ASM 242201.
       1 If the resistance values are out of the specified limits:
       2 If the resistance values are in the specified limits:
  • Do an electrical resistance test of the IDG 2 PMG stator ASM 242201 between:
    . Pins B/12 and B/13 (1 ohm plus or minus 0.15 ohm)
    . Pins B/12 and B/14 (1 ohm plus or minus 0.15 ohm)
    . Pins B/13 and B/14 (1 ohm plus or minus 0.15 ohm).
         a If the resistance values are out of the specified limits:
         b If the resistance values are in the specified limits:
  • Do a check of the wiring of the PMG stator and exciter field ASM 242201 for a short to ground, a short circuit or an open circuit between:
    . Pin B/12 of the IDG 2 and pin C/10 of the GCU 2
    . Pin B/13 of the IDG 2 and pin C/11 of the GCU 2
    . Pin B/14 of the IDG 2 and pin C/9 of the GCU 2
    . Pins C/10, C/11, C/9 and C/7 of the GCU 2 (short to shield of the PMG stator)
    . Pin A/9 of the IDG 2 and pin C/12 of the GCU 2
    . Pin A/10 of the IDG 2 and pin C/13 of the GCU 2
    . Pins C/12, C/13 and pin C/7 of the GCU 2 (short to shield of the exciter field).

    * If the wiring is not correct:
    * - Repair or replace as necessary.

    * If the wiring is correct:
    * - Replace the GCU-2 [1XU2] AMM 24-22-34-000-001 and AMM 24-22-34-400-001.
     (b) For the IDG P/N 740119 or the IDG P/N 766219:
  • Do an electrical resistance test of the IDG 2 exciter field between pins A/9 and A/10 (7.5 ohms plus or minus 0.75 ohms) ASM 242201.
       1 If the resistance values are out of the specified limits:
       2 If the resistance values are in the specified limits:
  • Do an electrical resistance test of the IDG 2 PMG stator ASM 242201 between:
    . Pins B/12 and B/13 (1.72 ohms plus or minus 0.39 ohm)
    . Pins B/12 and B/14 (1.72 ohms plus or minus 0.39 ohm)
    . Pins B/13 and B/14 (1.72 ohms plus or minus 0.39 ohm).
         a If the resistance values are out of the specified limits:
         b If the resistance values are in the specified limits:
  • Do a check of the wiring of the PMG stator and exciter field ASM 242201 for a short to ground, a short circuit or an open circuit between:
    . Pin B/12 of the IDG 2 and pin C/10 of the GCU 2
    . Pin B/13 of the IDG 2 and pin C/11 of the GCU 2
    . Pin B/14 of the IDG 2 and pin C/9 of the GCU 2
    . Pins C/10, C/11, C/9 and C/7 of the GCU 2 (short to shield of the PMG stator)
    . Pin A/9 of the IDG 2 and pin C/12 of the GCU 2
    . Pin A/10 of the IDG 2 and pin C/13 of the GCU 2
    . Pins C/12, C/13 and pin C/7 of the GCU 2 (short to shield of the exciter field).

    * If the wiring is not correct:
    * - Repair or replace as necessary.

    * If the wiring is correct:
    * - Replace the GCU-2 [1XU2] AMM 24-22-34-000-001 and AMM 24-22-34-400-001.

Subtask 24-21-00-710-086-G ** ON A/C NOT FOR ALL
D. 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 24-21-00-860-065-D ** 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 24-21-00-860-065-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 04:26:32 UTC
"WTRUIB" 2025