Fault Message:

ACPC SSPC PWR CARD1 (A2)/AFT PR PMP

Fault Code:

2451320ACP

Associated CAS:

ELEC SYS FAIL
Caution

AC Power Center (ACPC) Solid-State Power Controller (SSPC) Power Card has detected a failure with the initialization of the AC SSPCs, the control logic circuitry, and/or the load.

• AC Power Center (ACPC) (A54)
• Solid-State Power Controller (SSPC) 1
• Left AFT Boost Pump (B7)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

• If the pump is inoperative without CAIMS message and SSPC is IN, check wires between L Wing Feed Inhibit Pri Pumps switch, LH Fuel Cutoff switch and the SLC #1
• If the SSPC is always tripped without CAIMS message, check for a short between the pump and the SSPC #1

1. Swap SSPC 1 with SSPC 10.

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

2. Perform wiring checks between L AFT boost pump and SSPC 1.

   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.

3. Check for short circuit to GND at SSPC 1 as follows:

   From	To	Result
   P120-25	Ground
   P120-28	Ground
   P120-31	Ground

   1. If short circuit is found, go to step 6.
   2. If no short circuit is found, continue with next step.
      NOTE: Disconnect L AFT boost connector B7P1 and remove SSPC 1 card for short circuit check.

4. Check for open circuit/resistance consistency at SSPC 1 as follows:

   From	To	Result
   P120-25	P120-28
   P120-25	P120-31
   P120-28	P120-31

   1. If system checks are good, do close out.
   2. If fault remains, continue with next step.
      NOTE: L AFT boost connector B7P1 must be connected.

5. Replace L AFT boost pump.

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

6. Replace ACPC.
7. Do close out.