even simple autonomous code doesn't work??

OK so autonomous mode doesn't seem to have control of the robot...
We are putting our robot into autonomous mode by setting the tean number to 0 on the OI, yanking out the tether cable, and resetting.
We know that it's running the autonomous function in user_routines_fast.c, because we can put a printf in there and it'll print.

However.

If we put ANY statement controlling the pwm's-- no matter how simple-- our victors refuse to do anything but blink orange.
Even if we put
pwm01 = pwm02 = pwm03 = pwm04 = 255;
LIGHTS DON'T CHANGE... and if we hook a fan up to any of them, it doesn't spin.

Any ideas? The lights on the victors DO change when you're in autonomous, right?