Does the power light also blink when the wheels are on the ground?
If so check the error code generated by the TCU using the instructions found on
http://svx-iw.com in the SVXipedia.
This is just another reminder for me to scan the FSM on the list of inputs the TCU uses to determine when to transfer power to the rear wheels.
My dad found out that if you unplug the TPS all 4 wheels will spin in the air. The TCU, when seeing 0% throttle, sees no need to send power to the rear wheels.