Are you sure the engine has a decoder in it?
Dave
Lackawanna Route of the Phoebe Snow
Sounds like your locos don't have decoders. You can't just hook up a DCC system, throw an ordinary loco on the track and expect it to work. The loco must have a DCC decoder.
Dr. Frankendiesel aka Scott Running BearSpace Mouse for president!15 year veteran fire fighterCollector of Apple //e'sRunning Bear EnterprisesHistory Channel Club life member.beatus homo qui invenit sapientiam
The address on the EZ-Command for running a DC loco is 10. What address are you using for your loco. If it has a decoder it should be an address from 1 to 9. There are only a couple of reasons the motor would shriek while running with the EZ-Command. One is that it the loco has no decoder, just a light board. The other is that it has a bad motor or drive. If that's the case it should shriek when run on DC also. Now, what address button do you have to press to run your loco? If it runs only when the '10' button is pressed the loco has no decoder, which from the sound you describe and the fact that it does it with other locos seems likely. If it's a button from '1' to '9' then you have a more serious problem. The possibility of it being a wiring problem with the EZ-Command is virtually nil. The connectors fit only one way. I know about this type system. I used one for two years with no problems.
If the engine sings and groans and buzzes, but moves when you give the throttle a substantial turn, it means the engine is just fine, and so is the EZ-Command. It also means, as other gents suggest, that the perfectly fine engine does not have a decoder in it. The singing and groaning is the motor responding to current pulses that it was not intended to receive because those pulses come at the frequency of the digital track impulses put out by the EZ-Command...and all other DCC systems.
Or...
You have one of two other possibilites: plastic or metal rubbing on something it shouldn't, creating a harmonic resonance that translated into shrieking, or one or more of your bearings/bushings is dry.
-Crandell
My decoder of choice is the Digitrax DZ125. It's good for motor and light control and can fit into tight spaces. It made for Z Scale applications but can be used in N and HO Scale equipment without a problem. I have them in a pair a Athearn SDP40F locos and they run fine.