As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AFTER TAKEOFF WHEN RETRACTING LANDING GEAR ALL GREEN LIGHTS EXTINGUISHED AND RED GEAR UNLOCK LIGHT REMAINED ILLUMINATED. HYD PRESS CAUTION LIGHT REMAINED ON. GEAR WAS EXTENDED AND RED LIGHT WENT OUT AND 3 GREEN LIGHTS ILLUMINATED. UPON ARRIVAL FOUND HYD RES LOW. CHECKED ALL UPLOCK SWITCHES FOR PROPER RIGGING AND FOUND ALL ELECTRICAL INPUTS TO THE PC BOARD GOOD. SERVICED HYD RAN GEAR SEVERAL TIMES. REMOVED AIR FROM SYSTEM.