ok, some new info:
- the voltage on FAV solenoid is always around 13,6V
- I have tried installing a new FAV and solenoid assembly (from second kit) - no luck at all
- tested the pump - it works perfect (when disable jumper FAV and enable jumper SYS)
please, help!! how can I test that the mainboard is not broken?
today it worked for few minutes but later on stopped again ((((( should I check voltages on the mainboard diag pins?