Fault Message:

GROUND RDCP/WRG

Fault Code:

2844604PK

Associated CAS:

None

The Fuel Management Quantity and Gauging Computer (FMQGC) cannot sense the REFUEL/DEFUEL Control Panel (RDCP) data busses.

• Junction Box (JB6)/PCB1
• Junction Box (JB6)/PCB3
• Auxiliary Power Unit (APU) Start Contactor Assembly (ACSA) (A48)
• Refuel/Defuel Control Panel (RDCP) (A46)
• Refuel/Defuel Control Panel (RDCP) (A213)
• Fuel Management Quantity and Gauging Computer (FMQGC) (A47)
• Associated Wiring

Advisory Wire/Service Bulletin:

• 700-28-002 - Modification - Refuel/Defuel System - Addition of Refuel/Defuel Control Panel in Flight Compartment

Forum Articles/Infoservice/Newsletter: None

1. In the CAIMS PMAT navigate to check the status of the ground Refuel Defuel Control Panel (RDCP).

   1. CAIMS
   2. System Diagnostics
   3. 28-00 Fuel
   4. Computer (FMQGC CH. A(B))
   5. LRU TEST
   6. RDCP AND REFUEL VALVES DATA - CH. A

2. Go to page 2 for the RDCP AND REFUEL VALVES DATA - CH. A data page. Turn ON the ground RDCP panel.

   1. If the CAIMS does the discrete display OFF, go to step 4.
   2. If the CAIMS discrete displays ON, continue with next step.

3. Swap the Cockpit RDCP with the Ground RDCP.
   NOTE: If A/C has dual RDCP's then complete this step, If not go to next step.

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

4. Disconnect connector A46P1 at the ground RDCP. Add a jumper wire and connect to pins 2 and 3. Perform wiring check as follows:

   From	To	Expected Result	Result
   A46P1-12	A46P1-18	28 VDC
   A46P1-13	A46P1-17	28 VDC
   A46P1-18	Airframe Ground	Continuity
   A46P1-17	Airframe Ground	Continuity

   1. If wiring checks are good, go to step 6.
   2. If wiring checks are not good, repair defective wiring as required and continue with next step.

5. Reconnect A46P1 at the ground RDCP. Perform wiring check at the APU Start Contactor Assembly (ASCA).

   From	To	Expected Result	Result
   A48J1-T	Airframe Ground	28 VDC
   A48J1-U	Airframe Ground	28 VDC

   1. If wiring checks are not good, replace CB-A1 or CB-A3 or suspect the (ASCA) and do close out.
   2. If wiring checks are good, continue with next step.

6. Perform wiring check at JB6 for PCB1.

   From	To	Expected Result	Result
   TP-60	TP-30	28 VDC
   TP-61	TP-30	28 VDC
   TP 59	TP-30	28 VDC
   TP-30	Airframe ground	Continuity

   1. If TP-30 does not have a ground, repair GS67 or repair defective wiring and do close out.
   2. If TP-59 has power and TP-61 does not have power, replace PCB1 in JB6 and do close out.
   3. If TP-59 does not have 28 VDC, repair wiring to FMQGC or replace FMQGC and do close out.
   4. If wiring checks are good, continue with next step.

7. Perform wiring check at JB6 for PCB3.

   From	To	Expected Result	Result
   TP-31	Airframe ground	28 VDC
   TP-56	Airframe ground	Ground

   1. If wiring checks are not good, replace PCB3 in JB6 or repair defective wiring and do close out.
   2. If wiring checks are good, continue with next step.

8. Turn OFF aircraft power and rerack the FMQGC making sure it is fully and properly pushed into place. Is the fault still present?

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

9. Replace the FMQGC.
10. Do close out.