Fuel Pumps - Center Tank Pumps 1 And 2 Do Not Run And No Fault Indication Shown

TASK 28-21-00-810-833-A
Fuel Pumps - Center Tank Pumps 1 And 2 Do Not Run And No Fault Indication Shown

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

1. Possible Causes

C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (31QA), R25 at 121VU and C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (32QA), R26 at 121VU tripped
C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (31QA) 121VU
C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (32QA) 121VU

2. Job Set-up Information
A. Referenced Information

REFERENCE	DESIGNATION
AMM 28-21-00-720-001	Functional Test of the Center-Tank Fuel Control
AMM 33-14-00-710-001	Operational Test of the Lights

3. Fault Confirmation
Subtask 28-21-00-710-082-B ** ON A/C NOT FOR ALL

A. Not applicable, the fault is evident.

4. Fault Isolation
Subtask 28-21-00-810-082-B ** ON A/C NOT FOR ALL

A. Do the Operational Test of the Annunciator Light Test System AMM 33-14-00-710-001.
(1) Repair/replace as necessary any faults found in Para 4.A.
(2) Have the C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (31QA), R25 at 121VU and C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (32QA), R26 at 121VU tripped.

NOTE: The legends on the above C/Bs are incorrect:

31QA should read C/B-FUEL/CTR TK/PUMPS 1 CTL AND 2 IND
32QA should read C/B-FUEL/CTR TK/PUMPS 2 CTL AND 1 IND.

NOTE: If only one C/B operates, the FAULT legend of the related PUMPS P/BSW will illuminate as the indication supplies are cross connected.

(3) Reset the C/Bs if found tripped.
(4) If unable to reset the C/Bs in 4.A.(3), replace the C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (31QA) 121VU and/or C/B-FUEL/CTR TK/PUMPS 1 AND 2/CTL AND IND (32QA) 121VU.
(5) Do the Functional Test of the Center-Tank Fuel Control (Manual Mode) AMM 28-21-00-720-001.

[Rev.8 from Aug 2018] 2026.04.04 04:28:38 UTC