As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
JUST PRIOR TO V1, CONFIG - GEAR NOT DOWN. GEAR SHOWED 3 GREEN INDICATORS. CONFIG ALERT REMAINED ENTIRE FLIGHT INCLUDING AFTER SHUTDOWN. CONTINUED TO INDY WITH GEAR DOWN. LANDING AND TAXI IN UNEVENTFUL. CHECK CONTINUITY ON WIRES 16 AND 17 ON CONNECTOR D1489 AND WIRES CHECKED GOOD. FOUND THAT THE CARD M1000 WOULD WAS NOT SEATING IN THE CONNECTOR PROPERLY. READJUSTED CONNECTOR AND REINSERTED CARD. OPS CHECK PASSED.