What was found
R REV UNLOCKED CAUTION MESSAGE DURING CLIMB. LEVELED AT 17,000?, RAN QRH. QRH RESOLVED MESSAGE WITH EMER STOW.MEL 78-30-1CAT "C" REF AML 1805384: SMOD APPROVED IS REQUIRED DUE TO ODI (RTF)(FLIGHT 5128) RT THRUST REVERSER PER MEL 78-30-1. DUE TO NATURE OF FAULT & RESULTING QRH RESOLVING ISSUE, SUSPECT POSSIBLE PDU MOTOR BRAKE FAILURE. R & R RT T/R PDU IAW AMM 78-32-03. MANUALLY RAN RT T/R ACTUATING SYSTEM THROUGH FULL RANGE OF MOTION, NO DISCREPANCIES NOTED, ALL EICAS INDICATIONS NORMAL IN ALL STAGES OF TRAVEL. REFERENCE CP 31607246 FOR MICROSWITCH REPLACEMENTS & RIGGING. REFERENCE CP 31607247 FOR OPS CHECK OF RT T/R SYSTEM (PER MIP 78-440-1002-SKY) OPS CHECK GOOD.