As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
FLT 4008 - DURING PREPARATION FOR TAKEOFF, CREW NOTICED 4 AMBER CAS MESSAGES RELATED TO THE AIRCRAFT HYDRAULIC SYSTEM. AIRCRAFT RETURNED TO THE GATE. OUT-STATION MAINTENANCE RE-RACKED THE PSEU (PROXIMITY SENSOR ELECTRONIC UNIT). GROUND RUN CHECKED GOOD, AIRCRAFT RETURNED TO SERVICE.