BeBe is correct. To be a little more specific First I would look at what is called an electronic control Box which is located in a bracket under the solenoid. It is simply a process of unplugging the old box and replacing it with a new one. I carry a spare. I acquired the item from Side-power and the item number is ART. no. 6 12321. I will mention that I have replaced my solenoid with bigger ones as the originals were to small for the motor so therefore if you have the originals then it may take a different control box. The item number should be on the control box.
This will not help you much, but an electrician will probably find a fault in the control box. I have not seen the controls, but I am sure that one solenoid is not working. It is very unlikely that it is anything else. So start there and save some time. If you are coming to Gocek, I know that Emek Marine has parts for the 54 bow thruster and can help you.