How to "wake up" a decoder

[R L Smith]

I have a Kato engine with a Digitrax decoder that was installed 10 or so years ago.  This engine has been stored for about 5 years, and I think it ran OK the last time I used it.  I took it out of the jewel box today and it wouldn't run - a flicker of headlight, a grunt as it tried to move, and then nothing.

I completely disassembled it, cleaned the wheels and contacts, burnished the contact strips and the contact pads on the decoder board. My DVM shows contact from the wheels to the frame, but still no go.  When I attempt to read the address on the programming track, I get an "Err 02" message.

Is there a way to "wake up" a decoder?  What is the CV for a reset of an older Digitrax decoder?  (I have a Lenz system.)

Thanks in advance,

Ron

[peteski]

To reset the decoder see http://www.digitrax.com/tsd/KB675/resetting-a-mobile-decoder-to-factory-settings/

But before you do that, try running the model on DC. If the DC mode was enabled (as it id from the factory), it should run on DC.  If it doesn't then you most likely have a bad electrical contact somewhere or the decoder is fried.  The other indication that it might be an electrical contact problem is that you should be able to read CV values from a decoder on the programming track (even if bunch of settings are not correct).  I know that you checked.  Do the headlights flicker when you try to read the decoder on the programming track?

The flickering headlight is indicating that the decoder might be ok.  Again, trying to run it on DC should be helpful in determining the problem.  The other thing is that the motor might be the problem (maybe the oil in the bearings has solidified, or some gunk is covering the commutator).  Good test would be to remove the decoder and see if the motor will run if DC power is applied directly to it.  To get DC power, using a 9V battery is the easiest, or if you have a DC throttle, you could use that.

[ednadolski]

Good test would be to remove the decoder and see if the motor will run if DC power is applied directly to it.

With some decoders you can also use alligator clips to jump directly from the rails onto the power pickup pads on the decoder.  Just be careful not to accidentally short anything or jump to the wrong pads (which could be bad).

Ed

[djconway]

Ron,
I've seen this problem on  several of my older Digitrax decoders (DZ121 & DN93) in N scale. I have not found a solution other than replacing the decoder.

[peteski]

Ron,
I've seen this problem on  several of my older Digitrax decoders (DZ121 & DN93) in N scale. I have not found a solution other than replacing the decoder.

IIRC, Digitrax will "repair" any decoder for $17 plus postage.

[R L Smith]

Been a wee bit busy lately, but did have time to try a factory reset, which was ineffective.  The motor and gears trun freely by hand. I have another decoder (unfortunately of the same vintage, but never used) and I will make the replacement this weekend.

[djconway]

IIRC, Digitrax will "repair" any decoder for $17 plus postage.

New DZ136D decoders can be had for $16.80 with no postage and they can do so much more than the 16+YO models.

[peteski]

New DZ136D decoders can be had for $16.80 with no postage and they can do so much more than the 16+YO models.

Without going into details, I mentioned this exact fact to the Digitrax tech support people (during my recent attempt for a decoder exchange), but they just shrugged.

[bnsf971]

I have a Kato engine with a Digitrax decoder that was installed 10 or so years ago.  This engine has been stored for about 5 years, and I think it ran OK the last time I used it.  I took it out of the jewel box today and it wouldn't run - a flicker of headlight, a grunt as it tried to move, and then nothing.

I completely disassembled it, cleaned the wheels and contacts, burnished the contact strips and the contact pads on the decoder board. My DVM shows contact from the wheels to the frame, but still no go.  When I attempt to read the address on the programming track, I get an "Err 02" message.

Is there a way to "wake up" a decoder?  What is the CV for a reset of an older Digitrax decoder?  (I have a Lenz system.)

Thanks in advance,

Ron

Is the Kaptan tape under the decoder still intact? It may have deteriorated, causing a short.

[R L Smith]

update: with another round of cleaning contact areas, the original decoder resumed operating - except only at "lights on but no go" or a scale bazillion miles an hour. I swapped it out with a new-in-package decoder of the same vintage, but it had no response. Both decoders show "Err 02" on the programming track, despite the first one now zooming right along.

BNSF971, I did not inspect the tape closely, only verified it was still in place.  I'll look at that tonight - great idea.

In the meantime, I put the original analog board back in (couldn't believe I actually found it!) and the engine runs fine. If the kapton tape looks good, I will probably not pursue this any further and will sell it with the analog board.  If the tape does look bad, I will consider pursuing the exercise further.

Thanks to all who offered sugegstions.

RLS