There is no Solenoid 7 in the SOLENOID TEST menu, it skips from Solenoid 6 (Gumball Diverter) to Solenoid 8 (Outhole) 
Matthew
OK, here is a better guess - there is a setting in the ROM that says the knocker is not installed. It is adjustment 3.21 - it should be set to Off to utilise the knocker, but is probably set to something else.
