As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SEA - WHEN SELECTING NR 1 STANDBY HYDRAULIC PRESSURE ON DURING APPROACH CHECKLIST NR 1 STANDBY HYDRAULIC PRESSURE INDICATED ZERO. AFTER FLAP SELECTION INDICATOR STILL READ ZERO. MAIN PRESSURE INDICATED NORMALLY AND NO LIGHTS ILLUMINATED. ALL COCKPIT BREAKERS NORMAL. MAINTENANCE INSPECTED AND FOUND CIRCUIT BREAKER 2931 IN THE RIGHT AC CONTRACTOR BOX POPPED. RESET PER GMM 5-18-0. C/W SPU OPERATIONAL CHECK GOOD. NO PARTS REPLACED. AIRCRAFT RETURNED TO SERVICE.