for the past 4 days, I have been searching down a short causing half the layout to be down. As a result I redesigned my power sections and added 4 new ones (see previous post). While implementing this I also discovered numerous little issues such as the DB105 booster was not correctly wired to layout. I also rerouted numerous bus wires and generally cleaned up and further documented the power zone wiring, while also labeling a lot of things.
Finally found the short in West Pasco.
You see I use Caboose Industries 220S ground throws for industrial spurs and branch lines. These require 3 holes to be drilled close together and the 3 bare wire leads dropped through sub-roadbed then wired to power the frogs. Turns out the middle lead and one of the rail leads were touching and so when the switch was thrown one way it didn't short but did when thrown the other way...sigh..Thought I had looked at that earlier..Grr...must have jiggled it when I was rerouting the light cord underneath Pasco and above Walla Walla. Now all is well. Dropped some other leads down where I double gapped the power zones to ensure reliable track power.
Trains running again. Now time to go celebrate by seeing a movie and taking wife to dinner!!