I've got a sale pending on my surf planet, but I've still got the control stick in front of me. You should be able to throw a 5k pot on the 4 pin control port to test this board. Tie pin 1 to a pot leg, pin 2 to the wiper, and pin 4 to the other pot leg. As resistance between pin 1 and 2 drops, rider should turn left, and vica versa. If you put a 2.5k ohm resistor between 1 and 2 and another between 2 and 4, your rider should go perfectly straight.