Lionel 153IR not working properly?

Do you know if the two 153IR’s you are using are from the same batch.  I discovered a few years back that while Lionel kept the same sku#, they changed the electronics a bit and they did not function the same from version to version.  The reason I ask is because the color of the terminals in your picture looks different between the two, which may indicate different versions.

Try a search on the forum for 153IR and you should find several threads discussing wiring differences.

Jeffrey,

The problematic functionality you see may not be due to your connections or logic.

There were apparently at least three versions of the 153IR manufactured, each different in how they are to be connected, with the same product number (6-14111).

See this post/thread for a detailed, but sometimes rambling, discourse documenting the attempt to sort this out:

   Wiring Dual 153IR's to operate one signal light. Can it be done without relays? | R Whitley

As @MrMoe50 suggested check your two 153IR's to make sure that they are exactly identical.  They may not be.

Good luck with the effort.

Mike

How do I check if they are identical?

Never mind. I did a bit more experimenting. I switched the A and U terminals on one of the units - they may have been reversed by accident in the factory. All works fine now.

Thanks for the input and advice. I would have never changed the power leads.

@JEFFREY RUCKGABER 050219 posted:

Never mind. I did a bit more experimenting. I switched the A and U terminals on one of the units - they may have been reversed by accident in the factory. All works fine now.

Good to hear you had success.

In addition to the intentional changes put in by the factory over two or three variations (without changing the product number) an accidental reversal at the factory would add even more complications to the mix.

Important to remember.

Mike