As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
HYDRAULIC LIGHT ILLUMINATED AFTER SELECTING GEAR RETRACTION. MAIN PRESSURE DROPS TO 1800 PSI FOR 3-5 SECONDS THEN GOES UP. AIR RETURN TO MSP. MAINTENANCE REMOVED AND REPLACED HYDRAULIC PRESSURE SWITCH 9ML IAW SF 340 MM 29-10-45 OPS AND LEAK CHECKS GOOD ALSO REPAIRED GROUND WIRE AT MAIN HYDRAULIC PRESSURE TRANSDUCER CONNECTOR PLUG. ALL OPS CHECKS GOOD.