As reported to the FAA. Reports are unverified, and codes are left as the FAA publishes them.
What was found
SUPPLEMENTAL INFORMATION, DURING CLIMB OUT RECIEVED LT T/R UNLOCK CAUTION MSG. C/W QRH EMERG STOW WAS PRESSED. T/R STOWED VISUALLY VERIFIED ON GROUND. REV ICON AMBER, DID NOT EXTINGUISH. AIRCRAFT AIR RETURNED TO KORD FOR MX. REVERSER WAS DE-ACTIVATED AND PLACED ON MEL. AIRCRAFT REMOVED FROM SERVICE. R&R LT TR PDU IAW AMM 78-31. OPS CHECK GOOD, REMOVED PLACARD REMOVED FROM MEL.