As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
AIRCRAFT WAS GROUNDED: ON T/O GEAR FAILED TO RETRACT. RAN QRH PROCEDURE. RETURN TO DEPARTURE AIRPORT. FOUND MANUAL EXTENSION DOOR OPEN. PREFORMED INSPECTION OF DOOR SWITCH IAW AMM 32-34-00-820-802. PREFORMED ALTERNATE LANDING GEAR TEST IAW AMM 32-31-51-400-801 AND PREFORMED PSEU BITE TEST IAW AMM 32-09-00-810-801. ALL TEST CHECK GOOD.