No sound from tender (lionel 6-38683 loco & tender) Berkshire Jr. 2-8-4

I just finished fixing one of these with the same issue.

Check for broken wires going to the trucks on the tender.

There are four screws on the bottom of the tender which removes the shell.

That is where you will find the battery if one was installed.

Dave

Power in, bad speaker, broken wire, bad volume pot, defective boards.  All the various issue to check.  Some simple others more involved.  G

I sent in my new Berkshire to have the smoke unit fixed and received it back with no sound.  After opening the tender I found the RS card laying loose inside the tender.  Has anyone ever had a card come loose during shipment?  Plus after plugging the card back in it still did not produce any sounds.  I checked max volume knob to start with and cab 2 volume adjustments.  Engine lights up and moves but no sounds.  Any suggestions on what to check before I send it back again?

Harry

Sorry guys I forgot to mention this is a Lionel TMCC 779. 

Sorry everyone but after finding and reading different posts about sound boards I pulled the RS board and reseated it and all is working, Yeah!  I still do not understand how the RS board became loose during shipping when it was shipped in original shipping box. It is more likely it was loose to begin with when assembled or someone pulled it loose and forgot to reseat and it took two shipping events to cause the problem.