The lights on the 2hi and 4 hi switches come on when key turned on . when 4hi button pushed can hear transfer case motor shift but light on switch continues to flash. when 4lo switch is pushed nothing happens. I have no power on the black wire /white stripe which should energize the front differential. transfer case control module has power and gnd and the 4wd switches are sending power to the tccm. The tccm is sending 8v reference voltage to transfer case encoder. can twist mode a bit and all lights are lost on the switches. this suggest either connector losing connection or circuit board is losing connection . All fuses related to the 4wd have been tested and found to have power when appropriate. I am at my wits end with this trk. thanks for any help you might have