Fault Message:

GEN3 OIL OVERTEMP FAULT

Fault Code:

2423126LPS

Associated CAS:

GEN 3 FAIL
(Advisory)

The temperature of the oil in the Generator 3 is above the recommended limits.

• Variable Frequency Generator (VFG) 3 (G3)
• Generator Control Unit (GCU) 3 (A58)
• Associated Wiring

Advisory Wire/Service Bulletin:

• AW700-24-0598 - Variable Frequency Generator (VFG) GL511-1103-9 - Failure

Full Throttle Blog/Forum Articles/Infoservice/Newsletter: 

• Reference Instruction Letter (RIL) GX-0198 - Return to service following VFG bearing failure and/or VFG housing rupture.

Flight Operation Notifications Manual (FONM): None

NOTES:

• Prior to T/S procedures, perform a visual of generator 3 for heat distress. Confirm if the heat exchanger is blocked  with FOD.
• If there is physical evidence of overheating such as paint blistering then the VFG must be replaced.
• A GCU patch cable (GSE REF # 24X-24-02) can be used to swap GCU 1, GCU 2, GCU 3, GCU 4 and the APU GCU into a different position (for troubleshooting only).

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

1. Access CAIMS and check if the following faults are active:

   • 2423124LPS - GEN3 [DIFF PROTECTION FEEDER]
   • 2423200LPS - GEN3 DRIVE SHAFT FAIL/INVALID %N2

   Inspect the VFG for the following:

   • VFG oil filter bypass indicator tripped, and/or
   • Metal particles in the oil lines, and/or
   • VFG end frame cracked or breached, and/or
   • Oil sight glass cracked

   1. If there is a combination of the listed CAIMS active fault and VFG condition(s) perform RIL GX-0198
   2. If there is NO combination, continue with next step.

2. On the VFG 3, record the oil level in relation to the “ADD OIL” line on the sight glass.

   1. If oil level is above add oil line, replace VFG 3.
   2. If oil level is below add oil line, continue with next step.

3. Perform general visual inspection of the applicable main-generator oil tubes.

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

4. Disconnect GCU 3 connector A58P2 and VFG 3 connector G3P1. Perform a continuity check as follows:

   From	To	Result
   A58P2-24	Ground
   A58P2-60	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.

5. Perform a continuity check between GCU 3 and VFG 3 as follows:

   From	To	Result
   A58P2-24	G3P1-A
   A58P2-60	G3P1-M

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

6. Replace VFG 3.
7. Do close out.