Solution : https://service.sap.com/sap/support/notes/300872 (SAP Service marketplace login required)
Key words : 
transaction snls ->code pages ->converter ccc ->ccc statisticsscroll, enable control code handling, ccc-converter reason, ccc converteruntil release 4, ccc converter, early patch levels, longer generate hashes, symptom control codes, handled control codes, 6c diagnosis diagnosis 1
Related Notes : 
       
| 377059 | Control codes converted to points |