[Al Skierkiewicz]

Vin,
Tank drive will put the CIM motors into near stall when you try to turn. Since you describe using other CIMs for your ball shooter, we expect that you are using only two CIMs for drive. If the CIMs run fine when you remove the chain connecting the components you may have some serious bearing issues. Either the chains are not aligned or the weight of the robot cause significant friction when the robot is one the floor. However, what you describe also occurs when the Crio senses that the power supply is falling to below 5.5 volts. There are a few possibilities for this.
1. You have a loose connection or poor crimp on the #6 wiring from the battery to the PD. Check all connections to be sure the hardware is tight.
2. On rare occasions the 120 amp breaker is defective. If you tap on the red button very lightly and the lights blink, you have a bad breaker.
3. Use an voltmeter to measure the voltage at the input to the PD. (the two lugs connected to the battery and breaker) You should see somewhere in the range of 7-12 volts when you try to drive. If this value jumps down to 5 volts or lower, something is wrong. It might be that the charger is not working. If you are using the First charger, make sure that the buttons are pressed for 12 volts and 6 amp charge.
4.. Check for the +24 volt LED on the end of the PD where the Crio is connected. Does it blink off when you have a problem?