As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
UPON LANDING GEAR RETRACTION, THE RED UNLOCK LIGHT STAYED ILLUMINATED. THE HYD PRESS LIGHT STAYED ILLUMINATED AND STARTED FLASHING WITH ASSOCIATED MASTER CAUTION LIGHT. STAB MISCOMPARE LIGHT ALSO ILLUMINATED. EXTENDED GEAR, GOT THREE GREEN AND ALL LIGHTS WENT OUT. ON POST FLIGHT, NO DAMAGE, FOD OR HYDRAULIC ISSUES NOTED HYDRAULIC RES IS FULL. NO HYDRAULIC LEAKS NOTED. CORRECTIVE ACTION: REPLACED PRESSURE SWITCH. OPS CHECK GOOD. IAW CE-560XL AMM 27-40-00.