As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
BOI-ON FLIGHT 2399, RETURNED TO GATE, ERRATIC INDICATIONS NR 1 HYDRAULIC QUANTITY. INDICATOR BOUNCING BETWEEN 0-25 PERCENT NR 1 HYDRAULIC PRESSURE NORMAL. FLAPS AND BRAKES OPERATE NORMALLY. MAINTENANCE CLEANED CONNECTOR FOR HYDRAULIC QUANTITY TRANSDUCER AND BLED AIR FROM HYDRAULIC RESERVOIR. PERFORMED ENGINE RUNNING OPERATIONAL CHECK OF NR 1 HYDRAULIC SYSTEM. HYDRAULIC INDICATION REMAINED STEADY, NO FLUX NOTED. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.