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Just wondering if anyone has had trouble acsessing F13-F28 with a MTH Proto 3 Sound decoder. I have a HO MTH ESS44AC and I am unable to get these functions to work. I have a MRC Prodigy Advanced2 DCC system that supports F1-F28. I have tried to contact MTH service, they are useless. I can't find anything in the manual that talks about programming a certain cv to activate these functions. I appreciate anybody's help.


New Member
I have several MTH HO locomotives with ProtoSound 3 and am able to access all 28 functions on them. I have an NCE power cab. There is no CV to activate to enable these functions. When you called MTH service did you speak to an actual service technician? I've always been satisfied with the help I get from the technicians.

Can you access F13-28 on your non-MTH locomotives with the same MRC system?


Gomez Addams
Staff member
I am able to access F13-F28 on my other loco's. It sounds like I may have to send in my controller to have it reprogrammed.
If you have a local MTH dealer, you can take the engine to them to reflash the decoder. Sometimes during initial programming, not everything "takes" like it should.
I have had this happen to both QSI and Soundtraxx decoders. While rare, it does happen.

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