As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
(CAN) AFTER DEPARTURE GEAR WOULD NOT RETRACT WHEN GEAR UP WAS SELECTED. GEAR WAS RECYCLED BUT WOULD STILL NOT COME UP. THE ONLY INDICATIONS WERE THREE GREEN AND THREE RED LIGHTS. NO CAUTION OR AURAL WARNINGS. THE FLIGHT WAS RETURNED TO BASE. INVESTIGATION/ACTION, NOSE WHEEL CENTERING SENSOR WIRING FOUND SHORTED. SENSOR REPLACED IAW AMM 32-61-00.