As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
ORD - FLT 4169 - AIR TURN BACK TO ORD FOR ELECTRICAL SMELL IN COCKPIT. MOC WAS NOTIFIED BY DISPATCH. RIGHT LANDING LIGHT STOPPED WORKING DURING TROUBLESHOOTING FURTHER INVESTIGATION REVEALED ARCING AND BURNING ON THE LANDING LIGHT CONTACTOR. RAI CONTACTOR IAW 33-41-00, OPS CHECK GOOD. AIRCRAFT RETURNED TO SERVICE. (M)