Tsunami Steam Problem

[Paul Bowman]

Hey Everyone-

I'm having a strange problem with a custom installed Tsunami decoder, and was wondering if anyone had any experience with them. The decoder was working fine before.

1. Locomotive headlight won't turn on, but tender light will.

2. Locomotive moves forward normally, but not backward(starts, then stops, but sound keeps going as if the engine is moving)

The locomotive is a Key N&W J with a TSU-1000.

Thanks,

Paul

[gmpullman]

Hi, Paul

I have installed maybe two dozen DCC decoders in various brass engines. Every one of them has been challenging to overcome pick-up problems or shorting issues. Sound decoders being especially challenging.

First the headlight. Did it ever light? So check the polarity of the LED, be sure the correct resistor is in the circuit.

Could the drive be slipping due to binding in the running gear when in reverse? Some of my brass uses the silicone sleeve between the motor and gearbox.

Have you done a full reset on the decoder to see if that makes any improvement? I have had situations where a very slight, instintaneous short would scramble the decoder and only a reset would bring it back.

Some of the brass decoders I've installed have keep alive capacitors but these are no help when dealing with a short. Sometimes a handrail, pilot or trailing truck, cab apron or valve gear will cause a momentary short and stop the engine in it's tracks, so to speak.

Is there a plug or jumper wire between the engine and tender? Is it possible that that got reversed? Flipped over? Some of the pin connectors can plug in either way with only a dot of paint or mark of some kind to orient it.

Sometimes a set of test-stand rollers is handy to diagnose an engine on the bench so you can "poke around" while the running gear is in motion to try to find problems.

Good Luck, Ed

[Paul Bowman]

Ed,

The engine's headlight does turn on with another another button(f5), but I have yet to check for shorts and the connection between the engine and tender.

Thanks, Paul

[selector]

I wonder if your drive fouls for some reason when you attempt to make it move forward. I couldn't dream of what would let a drive move only in one direction as controlled by a decoder, but not the other direction unless it is mechanical. 

I would perform a factory reset.  Don't forget to cut power to the rails after the last button press, and then restore it once again.  If done properly, your decoder should not respond any more to any other addresses than "03".

[Paul Bowman]

Thanks for the replies.

I've found the problem- there's a bind in the gearbox, but only in reverse.

-Paul

[Geared Steam]

selector

I wonder if your drive fouls for some reason when you attempt to make it move forward. I couldn't dream of what would let a drive move only in one direction as controlled by a decoder, but not the other direction unless it is mechanical. 

 

I recently had a TSU-750 fail on the forward drive, and work perfectly in reverse. Soundtraxx told me to send it in and they would replace it under warrany, so it can and does happen.