What was found
SHORTLY AFTER TAKEOFF WHEN PILOT SELECTED GEAR UP THE GEAR INDICATED UNSAFE. HYD CAUTION ILUMINATED. PILOT SELECTED GEAR DOWN & PERFORMED EMERGENCY EXTENSION PROCEDURE. PILOT HAD 3 GREEN GEAR INDICATING & PERFORMED A NORMAL LANDING AFTER DIVERTING & RETURNING TO BASE. MAINT FOUND THE 100AMP HYD PUMP CIRCUIT BREAKER OPEN ON RT POWER JUNCTION BOX. MLG SWING & FUNCTION CHECKED MULTIPLE TIMES. VISUALLY INSPECTED DC ELECTRIC HYD MOTOR. TEST OF MOTOR AMP DRAW & FOUND NORMAL. ACCUMULATOR PRESSURE CHECKED & SYS PRESSURE CHECKED. RESERVOIR PRESSURE CHECKED & HYD FLUID QTY. ACFT WAS FLT CHECKED WITH MULTIPLE GEAR CYCLES & RETURNED TO SERVICE. THE PILOT QRH ONLY REFFERENCES THE HYD CTRL BREAKER ON PILOT CB PANEL & NOT HYDRAULIC PUMP BREAKER ON THE COPILOT PJB PANEL AS AN ITEM TO CHECK IN THE EVENT OF A HYD CAUTION.