As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
PDX - ON FLIGHT 2178, RETURNED TO GATE, AFTER PUSHBACK AND BRINGING ENGINES OUT OF FEATHER, NR 2 MAIN HYDRAULIC PRESSURE INDICATOR READING ZERO (MAIN HYDRAULIC PRESSURE INDICATOR INOP). MAINTENANCE CLEANED CONNECTOR AT THE PRESSURE TRANSMITTER. GROUND RAN AND ALL PRESSURE READING GOOD. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.