No Power to the REFUEL/DEFUEL PNL
TASK 28-25-00-810-817-A
No Power to the REFUEL/DEFUEL PNL
A. Fixtures, Tools, Test and Support Equipment
B. Referenced Information
3. Fault Confirmation
Subtask 28-25-00-865-057-A
Subtask 28-25-00-810-068-B ** ON A/C NOT FOR ALL
[Rev.8 from Aug 2018]
2026.04.04 04:39:38 UTC
No Power to the REFUEL/DEFUEL PNL
WARNING:
OBEY THE FUEL SAFETY PROCEDURES.
1. Possible Causes- MSW-REFUEL/DEFUEL CTL PNL DOOR POSITION [20QU]
- LEVER-L/G NORM CTL [6GA]
- diode module 80VD
- aircraft wiring
A. Fixtures, Tools, Test and Support Equipment
| REFERENCE | QTY | DESIGNATION |
|---|---|---|
| No specific | AR | MULTIMETER - STANDARD |
| REFERENCE | DESIGNATION |
|---|---|
| TSM TASK 24-67-00-810-801-A | Refueling not Possible |
| TSM TASK 28-42-00-810-870-A | Fuel - All FQIS Indicators Show Blank During Refuel on Battery |
| AMM 12-11-28-650-003 | Pressure Refuel with Automatic Control |
| ESPM 2052210 | |
| ESPM 2053210 | |
| ASM 246701 | |
| AWM 246701 | |
| ASM 282501 | |
| AWM 284201 | |
| AWM 284202 | |
| ASM 284203 | |
| AMM 32-31-11-000-001 | Removal of the Landing Gear Normal Control lever |
| AMM 32-31-11-400-001 | Installation of the Landing Gear Normal Control Lever |
Subtask 28-25-00-865-057-A
A. Table of the circuit breakers referred to in this procedure:
Subtask 28-25-00-710-068-A | PANEL | DESIGNATION | FIN | LOCATION |
|---|---|---|---|
| ** ON A/C ALL | |||
| 121VU | FUEL/RFL/DFL/SPLY | 2QU | L24 |
| 122VU | ELEC/REFLNG/NORM | 2PR | S27 |
| 122VU | ELEC/RFL/SPLY/LOGIC | 4PR | U29 |
| 122VU | ELEC/REFLNG/ON/BAT | 1PR | U28 |
B. Prerequisite test
(a) Do the test of the L/G control lever, as given in the procedure for the installation of the lever AMM 32-31-11-400-001.
(b) Do the test in Para. 3.C.
Subtask 28-25-00-710-067-A NOTE: This initial test is done to make sure that the L/G control lever (6GA) contacts operate correctly. A fault (example - high resistance contacts) on receptacle 6GA-A, between pins E and L, will not show during a L/G system check, as they are only used in the refuel system. The procedure that follows will remove a possible intermittent (spurious) condition that can cause the initial fault condition.
(1) Cycle the Landing Gear control lever 6GA as follows: (a) Do the test of the L/G control lever, as given in the procedure for the installation of the lever AMM 32-31-11-400-001.
(b) Do the test in Para. 3.C.
C. Test
(1) Make sure that the C/Bs that follow are closed:
4. Fault Isolation(1) Make sure that the C/Bs that follow are closed:
- C/B-1PR
- C/B-2PR
- C/B-4PR
- C/B-2QU.
- if the refuel panel will not power-up, do Para. 4.A., and then do the TSM procedure, Refueling not Possible (Ref. TSM TASK 24-67-00-810-801)
- if, during a battery refuel, the refuel/defuel flood light comes on, the refuel panel HI LVL lights come on and the DEFUEL/XFR/OPEN light comes on, but the FQI indicator displays on 5QT and 6QT show blank, do the TSM procedure (Ref. TSM TASK 28-42-00-810-870).
Subtask 28-25-00-810-068-B ** ON A/C NOT FOR ALL
A. Procedure
(a) The MSW-REFUEL/DEFUEL CTL PNL DOOR POSITION [20QU] .
1 Use a MULTIMETER - STANDARD to make sure that there is continuity between receptacle 20QU-A, pins D and F, with the door in the OPEN position ESPM 2052210.
(b) The LEVER-L/G NORM CTL [6GA] AMM 32-31-11-000-001 and AMM 32-31-11-400-001.
1 Use a multimeter to make sure that there is continuity between receptacle 6GA-A, pins E and L, with the lever in the DOWN position ESPM 2052210.
(c) The diode (part of the diode module 80VD between terminals 11 and 26 at 92VU).
1 Make sure that there is forward continuity between terminal 11 (cathode) and 26 (anode).
(2) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 246701:
(c) Do the tests given in Para. 3.B. and C.
(3) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 282501:
(c) Do the tests given in Para. 3.B. and C.
(4) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 284203:
(c) Do the tests given in Para. 3.B. and C.
(5) If the fault continues, do the related TSM Task in Chapter 24 (Ref. TSM TASK 24-67-00-810-801).
Subtask 28-25-00-810-068-D ** ON A/C NOT FOR ALL NOTE: This procedure only gives trouble-shooting for the control circuit for relay-8PR, between pin X2 and the ground on M/SW 20QU ASM 246701.
NOTE: When the C/Bs 1PR and 2PR are closed, 28VDC is supplied to pin X1 of relay-8PR. When the L/G control lever is in the DOWN position and the refuel panel door is open, a ground is supplied to pin X2 of relay-8PR. When the relay-8PR is energized 28VDC is supplied to the Refueling buses 501PP and 502PP.
(1) Do a check of and replace, if necessary, the items that follow: (a) The MSW-REFUEL/DEFUEL CTL PNL DOOR POSITION [20QU] .
1 Use a MULTIMETER - STANDARD to make sure that there is continuity between receptacle 20QU-A, pins D and F, with the door in the OPEN position ESPM 2052210.
(b) The LEVER-L/G NORM CTL [6GA] AMM 32-31-11-000-001 and AMM 32-31-11-400-001.
1 Use a multimeter to make sure that there is continuity between receptacle 6GA-A, pins E and L, with the lever in the DOWN position ESPM 2052210.
(c) The diode (part of the diode module 80VD between terminals 11 and 26 at 92VU).
1 Make sure that there is forward continuity between terminal 11 (cathode) and 26 (anode).
(2) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 246701:
- between the relay 8PR base, terminal X2 and the diode module 80VD, terminal 26 AWM 246701 AWM 284201 and AWM 284202
- diode module 80VD, terminal 11 and the landing gear lever connector 6GA-A, pin E
- between the landing gear lever connector 6GA-A, pin L and the refuel panel door M/SW connector 20QU-A, pin D AWM 284202
- between the refuel panel door M/SW connector 20QU-A, pin D and the aircraft ground point AWM 284202.
(c) Do the tests given in Para. 3.B. and C.
(3) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 282501:
- between the C/B 2QU and the relay 14QU, pin A2 and X1
- between relay 14QU, pin A1 and the connector 4024VC, pin L
- between the relay 14QU, pin X2 and the switch 20QU, pin A
- between the switch 20QU, pin C and the aircraft ground point.
(c) Do the tests given in Para. 3.B. and C.
(4) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 284203:
- between the C/B 8QT and the relay 14QU, pin B2
- between the C/B 8QT and the FQIC 3QT, connector AC pin 9E
- between the relay 14QU, pin C2 and the aircraft ground point
- between the relay 14QU, pin C1 and the FQIC 3QT, connector AC pin 8C
- between the relay 14QU, pin B1 and the panel 6QT, connector A pin E
- between the relay 14QU, pin B1 and the panel 5QT, connector A pin E.
(c) Do the tests given in Para. 3.B. and C.
(5) If the fault continues, do the related TSM Task in Chapter 24 (Ref. TSM TASK 24-67-00-810-801).
A. Procedure
(a) The MSW-REFUEL/DEFUEL CTL PNL DOOR POSITION [20QU] .
1 Use a MULTIMETER - STANDARD to make sure that there is continuity between receptacle 20QU-A, pins D and F, with the door in the OPEN position ESPM 2052210.
(b) The LEVER-L/G NORM CTL [6GA] AMM 32-31-11-000-001 and AMM 32-31-11-400-001.
1 Use a multimeter to make sure that there is continuity between receptacle 6GA-A, pins E and L, with the lever in the DOWN position ESPM 2052210.
(c) The diode (part of the diode module 80VD between terminals 11 and 26 at 92VU).
1 Make sure that there is forward continuity between terminal 11 (cathode) and 26 (anode).
(2) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 246701:
(c) Do the tests given in Para. 3.B. and C.
(3) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 282501:
(c) Do the tests given in Para. 3.B. and C.
(4) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 284203:
(c) Do the tests given in Para. 3.B. and C.
(5) If the fault continues, do the related TSM Task in Chapter 24 (Ref. TSM TASK 24-67-00-810-801).
NOTE: This procedure only gives trouble-shooting for the control circuit for relay-8PR, between pin X2 and the ground on M/SW 20QU ASM 246701.
NOTE: When the C/Bs 1PR and 2PR are closed, 28VDC is supplied to pin X1 of relay-8PR. When the L/G control lever is in the DOWN position and the refuel panel door is open, a ground is supplied to pin X2 of relay-8PR. When the relay-8PR is energized 28VDC is supplied to the Refueling buses 501PP and 502PP.
(1) Do a check of and replace, if necessary, the items that follow: (a) The MSW-REFUEL/DEFUEL CTL PNL DOOR POSITION [20QU] .
1 Use a MULTIMETER - STANDARD to make sure that there is continuity between receptacle 20QU-A, pins D and F, with the door in the OPEN position ESPM 2052210.
(b) The LEVER-L/G NORM CTL [6GA] AMM 32-31-11-000-001 and AMM 32-31-11-400-001.
1 Use a multimeter to make sure that there is continuity between receptacle 6GA-A, pins E and L, with the lever in the DOWN position ESPM 2052210.
(c) The diode (part of the diode module 80VD between terminals 11 and 26 at 92VU).
1 Make sure that there is forward continuity between terminal 11 (cathode) and 26 (anode).
(2) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 246701:
- between the relay 8PR base, terminal X2 and the diode module 80VD, terminal 26 AWM 246701 AWM 284201 and AWM 284202
- diode module 80VD, terminal 11 and the landing gear lever connector 6GA-A, pin E
- between the landing gear lever connector 6GA-A, pin L and the refuel panel door M/SW connector 20QU-A, pin D AWM 284202
- between the refuel panel door M/SW connector 20QU-A, pin D and the aircraft ground point AWM 284202.
(c) Do the tests given in Para. 3.B. and C.
(3) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 282501:
- between the C/B 2QU and the relay 14QU, pin A2 and X1
- between relay 14QU, pin A1 and the connector 4024VC, pin L
- between the relay 14QU, pin X2 and the switch 20QU, pin A
- between the switch 20QU, pin C and the aircraft ground point.
(c) Do the tests given in Para. 3.B. and C.
(4) If the fault continues:
(a) Do a check ESPM 2052210 of the aircraft wiring that follows ASM 284203:
- between the C/B 8QT and the relay 14QU, connector A pin B2
- between the C/B 8QT and the FQIC 3QT, connector AC pin 9E
- between the relay 14QU, connector A pin C2 and the aircraft ground point
- between the relay 14QU, connector A pin C1 and the FQIC 3QT, connector AC pin 8C
- between the relay 14QU, connector A pin B1 and the panel 5QT, connector A pin E.
(c) Do the tests given in Para. 3.B. and C.
(5) If the fault continues, do the related TSM Task in Chapter 24 (Ref. TSM TASK 24-67-00-810-801).