Fault Message:

GEN2 DELTA CURRENT FAULT

Fault Code:

2422118LPS

Associated CAS:

GEN 2 FAIL
(Advisory)

The Generator Control Unit (GCU) 2 detects between two phases a difference in output current larger than 35 A±5 A.

• AC Power Center (ACPC) (A54)
• Generator Control Unit (GCU) 2 (A57)
• Generator Line Contactor (GLC)
• Variable Frequency Generator (VFG) 2 (G2)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

A GCU patch cable (GSE REF # 24X-24-02) can be used to swap GCUs 1, 4 and 5 into position 2 or 3 (for troubleshooting only).

The GCU NVMs can only be downloaded at position #2 or #3.

1. Check for CAIMS message related to the ACPC short circuit fault. Clear/troubleshoot the message first if existed.

   1. If system checks are good, do close out.
   2. If fault remains, continue with next step.

2. Swap GCU 2 with GCU 3 (physically or using the GCU patch cable).
   NOTE: Use PMAT to monitor the fault on GCU.

   1. If system checks are good, replace GCU 2 and do close out.
   2. If fault remains, continue with next step.

3. Disconnect T1, T2, T3 and G at VFG 2. Perform continuity check (closed circuit= failure) at the terminal block of VFG 2 as follows:

   From	To	Result
   G2-T1	Ground
   G2-T2	Ground
   G2-T3	Ground

   1. If there is continuity, go to step 20.
   2. If there is no continuity, continue with next step.

4. Perform wiring checks (open circuit= failure) between VFG 2 and ACPC as follow:

   From	To	Result
   G2-T1	ACPC VFG2-T4
   G2-T2	ACPC VFG2-T5
   G2-T3	ACPC VFG2-T6

   1. If wiring checks are not good, repair defective wiring as required and do close out.
   2. If wiring checks are good, continue with next step.

5. Disconnect connector G2P1 on the VFG 2. Perform continuity check (open circuit= failure) on VFG 2 as follow:

   From	To	Result
   G2P1-F	G2P1-D
   G2P1-E	G2P1-D
   G2P1-J	G2P1-D

   1. If there is no continuity, go to step 20.
   2. If there is continuity, continue with next step.

6. Perform continuity check (closed circuit= failure) on VFG 2 as follows:

   From	To	Result
   G2P1-F	Ground
   G2P1-E	Ground
   G2P1-J	Ground
   G2P1-D	Ground

   1. If there is continuity, go to step 20.
   2. If there is no continuity, continue with next step.

7. Disconnect GCU 2 connector A57P2. Perform continuity check (open circuit= failure) between G2P1 and A57P2 as follows:

   From	To	Result
   G2P1-F	A57P2-41
   G2P1-E	A57P2-42
   G2P1-J	A57P2-50
   G2P1-D	A57P2-40

   1. If there is no continuity, repair defective wiring as required and do close out.
   2. If there is continuity, continue with next step.

8. Perform wiring checks (closed circuit= failure) between G2P1 and ground as follow:

   From	To	Result
   G2P1-F	Ground
   G2P1-E	Ground
   G2P1-J	Ground

   1. If wiring checks are not good, repair defective wiring as required and do close out.
   2. If wiring checks are good, continue with next step.

9. Disconnect ACPC connector A54P7. Perform continuity check (open circuit= failure) between A57P2 and A54P7 as follows:

   From	To	Result
   A57P2-49	A54P7-E
   A57P2-57	A54P7-F
   A57P2-63	A54P7-G
   A57P2-62	A54P7-H

   1. If there is no continuity, repair defective wiring as required and do close out.
   2. If there is continuity, continue with next step.

10. Perform wiring checks (closed circuit= failure) between A57P2 and ground as follow:

    From	To	Result
    A57P2-49	Ground
    A57P2-57	Ground
    A57P2-63	Ground

    1. If wiring checks are not good, repair defective wiring as required and do close out.
    2. If wiring checks are good, continue with next step.

11. Perform continuity check (open circuit= failure) between VFG 2 and K7 as follows:

    From	To	Result
    G2-T1	K7-A3
    G2-T2	K7-B3
    G2-T3	K7-C3

    1. If there is no continuity, repair defective wiring as required and do close out.
    2. If there is continuity, continue with next step.

12. Repair wiring (including inside ACPC) between VFG 2 and K7 as follows:

    From	To	Result
    G2-T1	K7-A3
    G2-T2	K7-B3
    G2-T3	K7-C3

    1. If fault remains, repair defective wiring as required and do close out.
    2. If system checks are good, continue with next step.
       NOTE: Call Bombardier for decision to repair ACPC wiring or replace ACPC.

13. Perform wiring checks (closed circuit= failure) between VFG 2 and ground as follow:

    From	To	Result
    G2-T1	Ground
    G2-T2	Ground
    G2-T3	Ground

    1. If wiring checks are not good, repair defective wiring as required and do close out.
    2. If wiring checks are good, continue with next step.

14. On current transducer 2 (LCTA 2), disconnect connector PL2. Perform continuity check (open circuit= failure) in ACPC between A54P7 and PL2 as follows:

    From	To	Result
    A54P7-E	PL2-1
    A54P7-F	PL2-2
    A54P7-G	PL2-3
    A54P7-H	PL2-4

    1. If there is no continuity, go to step 21.
    2. If there is continuity, continue with next step.

15. Perform continuity check (open circuit= failure) in ACPC between A54P7 and ground as follows:

    From	To	Result
    A54P7-E	Ground
    A54P7-F	Ground
    A54P7-G	Ground

    1. If there is continuity, go to step 21.
    2. If there is no continuity, continue with next step.

16. Perform continuity check (open circuit= failure) at connector within PL2 as follows:

    From	To	Result
    PL2-1	PL2-4
    PL2-2	PL2-4
    PL2-3	PL2-4

    1. If there is no continuity, go to step 18.
    2. If there is continuity, continue with next step.

17. Perform continuity check (short circuit= failure) at connector between JL2 and ground as follows:

    From	To	Result
    JL2-1	Ground
    JL2-2	Ground
    JL2-3	Ground

    1. If there is no continuity, go to step 19.
    2. If there is continuity, continue with next step.

18. Replace LCTA 2.

    1. If system checks are good, do close out.
    2. If fault remains, continue with next step.

19. Replace GLC 2 (K7).

    1. If system checks are good, do close out.
    2. If fault remains, continue with next step.

20. Swap VFG 2 with VFG 1.

    1. If system checks are good, replace VFG 2 and do close out.
    2. If fault remains, continue with next step.

21. Replace ACPC.
22. Do close out.