What was found
UPON SELECTING GEAR UP AFTER TAKEOFF RECEIVED ANTI-SKID INBD CAUTION, THEN A PARK BRAKE SOV CAUTION MESSAGE & GEAR WOULD NOT RETRACT. UPON SELECTING GEAR DOWN BOTH MESSAGES CLEARED & LANDING GEAR REMAINED DOWN. FLT 6427 REPLACED PARKING BRAKE SOV, PERFORMED LEAK CHECK, NO LEAKS, PERFORMED GEAR EXTENSION & RETRACTION IAW AMM, OPERATIONS CHECKED GOOD.