As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIR TURNBACK, DURING CLIMB ELEVATOR FEEL DIFF PRESSURE LIGHT ILLUMINATED FOR 10 MINUTES. LIGHT EXTINGUISHED AFTER 10 MINTES THEN ILLUMINATED AGAIN. LIGHT EXTINGUISHED ON DESCENT. HYDRAULIC PRESSURE AND QUANTITY NORMAL. REMOVED AND REPLACED MAIN HYDRAULIC RETURN FILTERS AND ELEVATOR FEEL COMPUTER PER MM.