L AUX PUMP OFF
(Status)

L AUX PUMP OFF (Status) shows when the conditions that follow occur:

• The L WING FEED INHIBIT AUX PUMP switch on the FUEL control panel is set to "OFF".
• The left auxiliary-pump pressure is low.

This troubleshooting applies when it is not under normal conditions.

• L WING FEED INHIBIT AUX PUMP switch (SDS1)
• Fuel Management and Quantity Gauging Computer (FMQGC) (A47)
• Fuel Control Panel (AP5)
• Ground Stud (GS852)
• Associated Wiring

Advisory Wire/Service Bulletin: None

Forum Articles/Infoservice/Newsletter: None

NOTE: The LH AUX PUMP OFF (Status) CAS does not display when the L WING FEED INHIB AUX PUMP switch is turned OFF.

1. Turn ON aircraft power and the CAIMS PMAT.

   • Access CAIMS.
   • Select System Diagnostics.
   • Select 28-00 Fuel.
   • Select Computer (FMQGC CH A(B))
   • Select LRU Test.
   • Select Cockpit fuel panel data - CH A(B).

2. Scroll through the pages and find Left AUX Pump Inhibit Panel Switch:
3. On the Fuel control panel (AP5) select the L WING FEED INHIBIT AUX PUMP switch.
4. Does the PMAT change from OFF to ON and ON to OFF?

   1. If the status changes, then go to step 11.
   2. If the status does not change, continue with the next step.

5. Remove the FMQGC and inspect the tray, connectors and pins. Make sure connector A47AP1 - C13 is not damaged, bent and is secured properly into place.

   1. If the check is good, continue with the next step.
   2. If the check is not good, rectify/replace as necessary.

6. Perform the wiring continuity test per the table below:
   

   SWITCH POSITION	FROM	TO	EXPECTED RESULT	RESULT
   R AUX PUMP SW DEPRESSED (OFF)	A47AP1 - C13	Airframe ground	Continuity

   1. If the wiring check is good, go to step 11.
   2. If the wiring check is not good, then continue with next step.

7. Remove the fuel control panel (AP5), and disconnect AP5P1.
8. Perform the wiring continuity test per the table below:
   

   FROM	TO	EXPECTED RESULT	RESULT
   AP5J1 - 15	AP5J1 - 48	Continuity
   AP5P1 - 15	Airframe Ground	Continuity

   1. If the wiring check from AP5J1 - 15 to AP5J1 - 48 is not good then suspect L WING FEED INHIBIT AUX PUMP switch (SDS1) or the Fuel Control Panel (AP5).
   2. If the wiring check from AP5P1 - 15 to airframe ground is not good then repair or replace wiring between fuel control panel and GS852 or GS852.
   3. If the wiring check is good then continue with the next step.

9. Perform the wiring continuity test per the table below:
   

   FROM	TO	EXPECTED RESULT	RESULT
   AP5P1 - 48	A47AP1 - C13	Continuity

   1. If the wiring check is good, continue with next step.
   2. If the wiring check is not good then repair or replace the wiring from the Fuel Control Panel to the FMQGC.

10. Re-connect AP5P1 and re-install the Fuel Control Panel.
11. Re-install or re-rack the FMQGC making sure it is fully and properly pushed into place. Is the fault still present?

    1. If the CAS does not display, then go to next step.
    2. If the CAS displays, then do close out.

12. Suspect the FMQGC (A47).
13. Do close out.