Solution : https://service.sap.com/sap/support/notes/535797 (SAP Service marketplace login required)
Key words : 
service data download reason, short dump 'conne_import_conversion_error', date collection, transaction sdcc, system writes, terms sdcc, patch level < 173, patch level >= 173, /3 release 6, 20 terminates
Related Notes : 
       
| 530576 | 6.20 kernel patch level <173: IMPORT FROM DATABASE critical | 
| 520280 | Known errors in the Solution Manager (Release 2.10 or 0.xD) |