I'm trying to control a 4 wire servo that was used in an RC car for the steering. It has two power connections, but I can't make sense of the other ones. If there is power on the red and black wires, the motor turns into one position and stays there, no matter what I put on the other wires. I also tried to vary the voltage of the power, no difference. How can I control its position?
The board it was connected to: https://drive.google.com/file/d/0B8Ox1li7YRxoREt1Z3RNcXp4OU0/view?usp=sharing