I have a craftsman garage door opener, 1/2 hp motor, approx 10 years old. Door opens fine, closes about a third of the way, then must be prompted several times with remote or manual switch to get fully closed. Sensors have been cleaned, lights do not flash off an on... is this a solenoid or relay issue?

I tried everything when mine did the same thing, and it is the same model as yours. Last week a repair man came out and adjusted the tension, along with realigning the sensors and it started working again. When you pass by the sensors, do the lights flash on the opener?