B757 flight crew reported the flaps disagree light illuminated while the flaps were moved from 20 to...

Attributes
ACN	1449232
Time
Date	201705
Local Time Of Day	0001-0600
Place
Locale Reference	ZZZZ.Airport
State Reference	FO
Environment
Flight Conditions	VMC
Light	Night
Aircraft 1
Make Model Name	B757-200
Operating Under FAR Part	Part 121
Flight Phase	Final Approach
Flight Plan	IFR
Component
Aircraft Component	Flap/Slat Indication
Person 1
Function	First Officer Pilot Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Person 2
Function	Captain Pilot Not Flying
Qualification	Flight Crew Air Transport Pilot (ATP)
Events
Anomaly	Aircraft Equipment Problem Less Severe

Narrative:

While completing approach and landing to ILS; te (trailing edge) flap disagree EICAS and light appeared while going from flaps 20 to 25. At approximately 1500 ft while slowing to Vref20 (146 KIAS) I called for flaps 25. The EICAS message and light came on indicating a disagree. The before landing checklist was complete to final flaps. I was stable at 146; on the glideslope with the runway in sight and cleared to land. We decided to continue the approach as the safest course of action due to the speed and stability of the aircraft; as well as the weather and length of runway available. We did not move the flaps at all after landing. Upon ramp connecting the gpu; the message went away; the flap indicator went to 25; and all indications of the issue went away. Maintenance reported no problems found.

Original NASA ASRS Text

Title: B757 flight crew reported the flaps disagree light illuminated while the flaps were moved from 20 to 25 degrees. All indications went to normal when a GPU was connected on the ramp.

Narrative: While completing approach and landing to ILS; TE (Trailing Edge) FLAP DISAGREE EICAS and light appeared while going from flaps 20 to 25. At approximately 1500 ft while slowing to Vref20 (146 KIAS) I called for flaps 25. The EICAS message and light came on indicating a disagree. The Before Landing checklist was complete to final flaps. I was stable at 146; on the glideslope with the runway in sight and cleared to land. We decided to continue the approach as the safest course of action due to the speed and stability of the aircraft; as well as the weather and length of runway available. We did not move the flaps at all after landing. Upon ramp connecting the GPU; the message went away; the flap indicator went to 25; and all indications of the issue went away. Maintenance reported no problems found.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.

B757 flight crew reported the flaps disagree light illuminated while the flaps were moved from 20 to 25 degrees. All indications went to normal when a gpu was connected on the ramp.