What was found
D: THIS IS AN **ODI EVENT** - UPPER MGMT /SMOD APPROVAL REQ'D TO RTS THIS A/C AFTER CAMPS COMPLETE / C: MCI / SEE A/C MX LOG'S 956358 & 955518 (FLIGHT 5123 - FILED CLOSED) DID OPERATIONAL CHECK OF THE STAB-TRIM SYSTEM REFERENCING THE APPLICABLE STEPS IN AMM 27-40-00. COULD NOT DUPLICATE THE DISCREPANCY. TROUBLESHOT PER FIM 27-40-00. AFTER DOING SELF TEST OF THE HSTCU FOUND THE CHANNEL B FLAGGING IN THE MDC. REMOVED AND REPLACE THE HSTCU REFERENCING THE APPLICABLE STEPS IN AMM 27-41-00. OPS CHECK GOOD AT THIS TIME. NO FURTHER MESSAGE SHOWN AT THIS TIME. COMPLIED WITH CATII RETURN TO SERVICE TASK CARD 34-220-1021-SKY.