Toyota Repair: Blinking 2WD/4WD Switch Light, dash switch, wiring connector

Question
2000 Tundra V8  When the 2/4WD switch is pushed it lights green then goes out and then flashes continuously.  I climbed under the truck and when the button is pushed the actuator on the transfer case engages but the actuator on the diff does nothing. I connected test leads to pins 2 and 6 on the connector on the actuator and applied power.  The actuator engaged and disengaged.  I then took my DC meter and checked pins 2 and 6 on the wiring connector for voltage when the button was pushed.  No voltage was present either on the engage or disengage push of the button.  I checked and could not find a fuse for the actuator but did find a 20A fuse for 4WD and it is fine.  I'm stumped on where to go next.

Answer
When the dash switch is pushed the signal goes to the 4 wheel drive control ECU,from there it goes to the actuator to engage it, if the actuator is known to be good the most likely cause may be an open circuit between the ecu and the actuator or the ecu itself.