Scan tools not communicating due to voltage on PIN 3
 

Tried several scan tools including Duramentric enthusiast without success..."communication error"....tech support at Durametric had me check voltage on pin 3 and yes I have 11V with key on. Similar thread a while back with no resolution. Does not appear to be radio, amp or any sound system component...ruled that out....has anybody had success figuring this out?

Thanks in advance.