grcauto, I am trying to understand what you said.."When you have a network that has an issue where one of the modules is pulling the network down...." This can only happen if at least one of the module is shorted out. If that is the case then ground is solid and not floating or disconnected. This contradicts with your statement of ground being open. Now if ground is open or making a weak contact due to cold solder then you cannot pull the node or network bus down because no current is flowing. Another contradiction to your statement. Your thoughts or anyone else comments will be appreciated.