As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
WHILE TURNING ON HYDRUALIC PUMPS FOR STARTUP CHECK LIST, RAT PRESSURE GREEN LIGHT ILLUMINATED AND AC WAS RETURNED TO A GATE TO BE WORKED , MTX GROUNDED AC AND TROUBLESHOT .MTX REPLACED RAT CHECKOUT MODULE IAW AMM-29-21-11 NO HYDRAULIC LEAKS NOTED . MTX RETURNED AC TO SERVICE .