Test the mode control motor.
You have to be kidding me. He gave you the first step to troubleshooting and you told him that you didn't know how to do it or where it even was. If you can't do it, the next step would be having someone that can.Well ain't that nice...well thanks for the help...I'll troubleshoot somewhere else.
You have already conceded that you are unable to troubleshoot. The somewhere else you are headed is straight to a mechanic to pay a lot of money.I'll troubleshoot somewhere else.