Emblemdhc

Dear Sir
Yes nav tuning is from Garmin GNS 530 only
i think ARINC Adapter KDA-689 is only for Show information to Both PFD 
we also check wiring 18,19,20,22 of both GNS 530 found good
 
and these 3 splices behind of backshell of KDI-574 i also checked splices its in good condition
yes we dissconnect GNS1 and check with GNS 2 sometimes its work or sometimes not (intermitent condition)

when i  powered the aircraft on in morning for first 10 mintue DME working fine from both NAV selections 
but after that DME from NAV 1 stop working 
now we suspecting the GNS 530 and KDI 574 
maybe we will get GNS 530 and KDI 574 for testing in few  days.