As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
DURING FLIGHT NR 3113, LANDING GEAR FAILED TO RETRACT. AIR RETURN TO YOW. A/C FERRIED TO DTW. MAINTENANCE JACKED A/C AND PERFORMED FUNCTIONAL TEST OF EXTENSION AND RETRACTION OF LANDING GEAR IAW CHAP 32-30. COULD NOT DUPLICATE DISCREPANCY. INSPECTED GEAR FOUND NO MECHANICAL DEFECTS. CLEANED AND LUBRICATED LT AND RT MLG UPLOCK SWITCHES. ALL CHECKS GOOD IAW CHAP 32.