Backup battery kills Railsounds

What locomotive? 

Thank you kindly for the response Mike. It's a CP Legacy GP-35, 6-39557. With the battery installed, only the air release sound is produced when the loco is reset. Otherwise no sounds at all, unless battery is removed. Sounds work fine in TMCC / Legacy mode, just not in conventional.

Is the battery a new battery?  If so, I wonder if the battery cable could be reversed in your engine?  I would think this would be an issue with the battery, wiring, or the RailSounds board.  Pretty hard to imagine it's any farther up the command chain.

Thanks. I've tried fresh batteries. Hadn't thought about reversed polarity. I'll check that out. Seems like it would be more difficult to cram the connector on backwards, but it's possible. I haven't taken the engine apart yet, but I wonder if the backup battery leads go directly to the Railsounds lite card, or somewhere else. I'm not really familiar with the wiring details and card functions in newer Legacy locos.

I'm thinking manufacturing error or just one cable got put together reversed polarity.  You'd have to open it up to check it, so if it's under warranty, I'd send it back.

The battery goes to the RailSounds Legacy (RSL3) PCB.   If the battery is reversed, you will damage the RSL board, please be careful.  Please double check the battery is fresh, and if that is not the cause, the RSL is most likely in need of replacement. 

Jon

SantaFeFan posted:

The battery goes to the RailSounds Legacy (RSL3) PCB.   If the battery is reversed, you will damage the RSL board, please be careful.  Please double check the battery is fresh, and if that is not the cause, the RSL is most likely in need of replacement. 

Jon

Thank you for the helpful advice and suggested potential source of the issue. I will be mindful of the proper polarity when I assess the situation.

Please post your findings.

What did you find??????

Marty Fitzhenry posted:

What did you find??????

Yes, inquiring minds want to know.

I just finished investigating this problem. The 9V backup was attached to the RSL3 PCB with the correct polarity. The source of the issue is the RSL3 card. I swapped it out with a good one from another loco, and then everything works fine. Because this remains the only issue with this card, I'll just keep it as-is. It's not worth the money to replace this costly card for the rare occasions when I might run it conventionally and want backup Railsounds operation. It sure is a strange failure though!

Keep it and swap wires in the plug.

Marty Fitzhenry posted:

Keep it and swap wires in the plug.

He said the wiring was correct, didn't he?

correct John.