B757-200
Flight Crew Air Transport Pilot (ATP)
Aircraft Equipment Problem Less Severe
Flight Crew Overcame Equipment Problem
Aircraft
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.
[Report narrative contained no additional information.]
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.