Fault Message:

DCPC SPDA DC ESS BUS FEEDER CARD A4

Fault Code:

2460404DCP

Associated CAS:

ELEC SYS FAIL
(Caution)

Voltage or trip status of any programmable Solid-State Power Controller (SSPC) on the Feeder Card is detected not in commanded state. Detected at power-up or continuous Built-In Test (BIT).

• DC Power Center (DCPC)
• Secondary-Power Distribution Assembly (SPDA) 1 (A13)
• Essential (ESS) Bus Feeder Card
• Battery/Ram-Air-Turbine (BATT/RATT) Card
• Left Microprocessor Card (p/o A20)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

The following are the main functions of DCPC SPDA DC ESS Bus Feeder card:

• Provides for power switching and load protection for four SPDA feeders on DC ESS Bus
• Monitors SSPC status
• Monitors DC ESS bus voltage status
• Monitors fuse and diode status on DC ESS Bus (EM 3)

1. Access the Signboard menu on the EMS CDU as per AMM TASK 24-00-00-946-801. Press on the “TEST” button on EMS CDU. On the line “ASSEMBLY”, make a selection of “DCPC”. On the line “SWAP MICROPROCESSORS” make selection of swapping from one side to the other. Is the fault resolved?

   1. If YES, replace the now inactive microprocessor and do close out.
   2. If NO, continue with next step.
      EMSCDU - Signboard Test Menu

2. Swap SPDA DC ESS BUS FEEDER Card with SPDA DC BUS 1 FEEDER Card. Did the fault follow?

   1. If YES, replace SPDA DC ESS BUS FEEDER Card and do close out.
   2. If NO, continue with next step.

3. Verify the voltage references input of the SPDA DC ESS BUS FEEDER Card. Remove the SPDA DC ESS BUS FEEDER Card, BATT/RATT Card and the Left Microprocessor Card from the DCPC. Perform a continuity check as follows:

   From	To	Result
   P331A-13/14	Ground
   P331C-13/14	Ground
   P331C-16	Ground

   1. If there is continuity, replace DCPC and do close out.
   2. If there is no continuity, continue with next step.
      DCPC SPDA DC ESS BUS FEEDER CARD A4

4. Perform a continuity check as follows:

   From	To	Result
   P331A-13/14	P2A/B/C-38/39
   P331C-13/14	P410A/B/C-38/39
   P331C-16	P2A-46

   1. If there is no continuity, replace DCPC and do close out.
   2. If there is continuity, continue with next step.

5. Swap the right Microprocessor with the left Microprocessor. Is the fault resolved?

   1. If YES, replace right Microprocessor and do close out.
   2. If NO, replace BATT/RAT interface card and do close out.

6. Do close out.