914 fuel pump quit

On a recent flight in my Searey . I was running on pump 2 and landed with out issue and shut down to pick up passenger. Upon startup the engine started to quit after a short runup and switched to pump 1 which engine resumed  full power. Upon getting back to base and  trouble shooting neither pump runs on battery until start up and then only when selecting pump 1 does fuel flow. At that time both pumps are actually running together even though only #1 is selected. So question is where is the problem as both pumps are functioning so it has to be a connection problem somewhere. I as getting power to the switches as both indicators light up when selected but don't understand where the fault would be. Looking at wiring diagram the fail safe of the magnetos running both pumps is energizing  both  pumps to run. So feel there must have been a disconnect somewhere but fail to see where .Any help much appreciated.