Fault Message:

GEN2 OPEN POR/FEED/GEN FAULT

Fault Code:

2422108LPS

Associated CAS:

GEN 2 FAIL
(Advisory)

Generator Control Unit (GCU) 2 has detected a failure (open circuit) associated with the Open Point Of Regulation (POR)/FEED/Generator circuit and consequently Generator 2 trips off-line. Inhibited during Take-Off and Landing.

• AC Power Center (ACPC) (A54)
• Generator Control Unit (GCU) 2 (A57)
• 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. Swap GCU 2 with GCU 1 (physically or using the GCU patch cable). Is the fault still present?

   1. If NO, replace GCU 2 and do close out.
   2. If YES, continue with next step.

2. Disconnect connector GCU 2 (A57P1) and ACPC (A54P7). Do a continuity check as follows:

   From	To	Result
   A57P1-A	Ground
   A57P1-B	Ground
   A57P1-C	Ground

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

3. Do a continuity check as follows:

   From	To	Result
   A57P1-A	A54P7-A
   A57P1-B	A54P7-B
   A57P1-C	A54P7-C

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

4. Do a continuity check as follows:

   From	To	Result
   VFG 2 stud T1	ACPC VFG 2 stud T4
   VFG 2 stud T2	ACPC VFG 2 stud T5
   VFG 2 stud T3	ACPC VFG 2 stud T6

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

5. Disconnect ACPC studs T4, T5 and T6. Do a continuity check as follows:

   From	To	Result
   ACPC VFG 2 stud T4	Ground
   ACPC VFG 2 stud T5	Ground
   ACPC VFG 2 stud T6	Ground

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

6. Do a continuity check on the ACPC as follows:

   From	To	Result
   A54P7-A	Ground
   A54P7-B	Ground
   A54P7-C	Ground

   1. If there is continuity, go to step 9.
   2. If there is no continuity, continue with next step.

7. Do a continuity check on the ACPC as follows:

   From	To	Result
   A54P7-A	ACPC VFG 2 stud T4
   A54P7-B	ACPC VFG 2 stud T5
   A54P7-C	ACPC VFG 2 stud T6

   1. If there is no continuity, go to step 9.
   2. If there is continuity, continue with next step.

8. Swap VFG 2 with VFG 1. Is the fault still present?

   1. If NO, replace VFG 2 and do close out.
   2. If YES, continue with next step.

9. Replace ACPC.
10. Do close out.