I need help, I have MED17.4.2, trying to read with kess and it sometimes asks to erase defects time "preparation for rolling code not carried out, vehicle has this dtc on RT6 error F300 and on BSM telecoding error B1003 00 could that be the problem? because kess it says it can be read via obd, or is this wrong?

sorry for the translator if it wasn't clear

Try to read in boot mode with KTAG, can read also as virtual read with a lot of tools,or by ECU pin .