Solution : https://service.sap.com/sap/support/notes/757869 (SAP Service marketplace login required)
Key words : 
code page conversion failed             rc = 2or, code page conversion failed             rc = 2x, <physical cluster table> <cluster key>mycluster, input code page matches, input code page correctly, erroneous source code page, input code page, code page conversion, physical cluster table, <physical cluster table>
Related Notes : 
       
| 89384 | Checking cluster tables with R3check |