Fuel Pumps - L #amp# R Wing Tank Pumps 1 Do Not Run And No Fault Indication Shown

TASK 28-21-00-810-831-A
Fuel Pumps - L & R Wing Tank Pumps 1 Do Not Run And No Fault Indication Shown

WARNING: OBEY THE FUEL SAFETY PROCEDURES.

1. Possible Causes

C/B-FUEL/PUMPS/1/L CTL AND R IND (3QA), R23 at 121VU and C/B-FUEL/PUMPS/1/R CT AND L IND (4QA), R28 at 121VU tripped
C/B-FUEL/PUMPS/1/L CTL AND R IND (3QA) 121VU
C/B-FUEL/PUMPS/1/R CTL AND L IND (4QA) 121VU

2. Job Set-up Information
A. Referenced Information

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

3. Fault Confirmation
Subtask 28-21-00-710-080-A

A. Not applicable, the fault is evident.

4. Fault Isolation
Subtask 28-21-00-810-080-A

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/PUMPS/1/L CTL AND R IND (3QA), R23 at 121VU and C/B-FUEL/PUMPS/1/R CT AND L IND (4QA), R28 at 121VU tripped.

NOTE: If one C/B only 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 Para 4.A.(3), replace the C/B-FUEL/PUMPS/1/L CTL AND R IND (3QA) 121VU and/or C/B-FUEL/PUMPS/1/R CTL AND L IND (4QA) 121VU.
(5) Do the Operational Test of the Wing-Tanks Fuel Control AMM 28-21-00-710-001.

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