DIAGNOSIS The control board is not receiving power. The most common cause is a blown thermal fuse on the logic board.
FIX Unplug the blender. Remove the base shroud by unsnapping it. Locate the logic board. Check the small, rectangular thermal fuse for continuity with a multimeter. If it's blown, you must replace the entire logic board. Blendtec sells the board as a single assembly.
IF THAT DIDN'T WORK Check the power cord connection where it plugs into the logic board. The internal connector can come loose from rough handling.
HEADS UP The logic board replacement requires soldering the motor wire connections. If you're not comfortable with that, take it to a service center.