Another Locomotive In Need Of Repair

My New York Central ALCO PA unit broke down. The PB unit is still working just fine. I will have to take the PA unit to Brasseur Electric Trains in Saginaw Michigan for repair. I already have an Ann Arbor GP38 there for repair to have the can motor replaced. It looks like I am having trouble keeping my locomotives running. The PA unit is getting the electricity to the motor but the motor is not running. I just don't know what the problem might be, but I hope I don't need to replace the motor in this locomotive as well.