Just a follow up in case you ever have the same problem. I planned on taking it to a service center but as per a suggestion above, I called Minn Kota. They were very helpful and said that because I was having problems with both speed and power steering it was probably a wiring issue. There are two motors involved and the chance of both being defective was possible but remote. I double checked the wiring and indeed there was a wire crossed.
Saved me from taking the motor to a service center, waiting two weeks to have them call me to tell me there was nothing wrong with the motor.