Atlas digital loco problem?

"Tony" wrote

more than once, at least. Is there a QC seal underneath the decoder? (well, for that you have to open that loco, avoid this when you intend to return the loco under warranty). Following tests will work w/ a unmodified (unopened) loco:

trouble-shooting questions hopefully leading to answers:

a) do the lights work in analog mode? (if yes, that part of the decoder is working, as only the motor is jumpered)

b) can you read CV's when in digital mode? (any! try at least cv01, and also cv29)

c) can you make a factory reset (in digital mode) of the decoder, by writing the value 33 (decimal) to either register 8 (in register mode) or to cv08, and try your tests again?

/jw

Tony,

Check the dual-mode decoder, the 'jumper' may be set for DC(that may the default).....

Jim Bernier

T> Hi,

Tony,

What's the part # for this locomotive, as found on the end of the box?

The early run Atlas Dash 8-32BHW's were dual mode decoder equipped, and came with the decoder set to "analog."

The latest runs of the model are an either/or propostion. The digital versions come with the four function decoder, carry a 9000-series part number, and are set in digital mode by default. The analog versions have no decoder at all (even though the light board is of a similar size and shape as the decoder), and carry a 7000-series part number (IIRC), as well as packaging indicating "silver series."

It's very easy to get the two versions confused, as it can be easy to mistake the difference between "DCC Ready" (which Atlas advertises the silver-series analog models as), and "DCC equipped."

If it's the latest run, it's also possible the model may be an analog version accidentally mispackaged. Atlas tapes the plastic cover piece to the foam cradle, so if that seal was broken, the model may have been removed and swapped out by the retailer. If it was sealed, it could be a boo-boo on the factory's part. On the latest run, an easy way to spot the difference between an analog and digital model, is to turn it over and look under the front steps. The ditch light wire leads, even though very small, can be seen running from the steps up under the frame. The analog version, as well as the early run model, won't have them...

All of the above hints may work, or you could have a bad decoder. If all else fails, call Atlas at 908-687-0880, tell them you have a decoder problem and would like to talk to Ed. He's been a great help to me in the past with a bad decoder. Chooch

Hi,

Thanks for the suggestions. Here are some answers to your questions,

1. The Atlas part number is #9077, and the box is marked as 'decoder equipped'
2. The instructions indicate that the decoder is set in analog mode, and that a jumper needs to be re-positioned to operate in DCC. This was the case, and as I mentioned the loco operated fine in analog mode out of the box. I had to remove a piece of the shell to get to the decoder, and the jumper is clearly marked as analog/DCC.
3. I moved the jumper back to analog mode and tried the lights, and they did not work. I guess this indicates a bad decoder?
4. I tried reading CV1, but get 'Er2', which translates to 'no value found' -or- 'no response was received from the decoder'.
5. I tried setting CV8 to 33, but again got 'Er2'.

Could it be possible that a wire needs to simply be 'plugged in' ?

Thanks, Tony

"Tony" wrote

Atlas Master Series AT-9077 AMTRAK California blue/silver/yellow

except the lights, see below, or did they work initially?

not alone, but: strike 1 (*) (another possibility is that the decoder would be working, but has been programmed in cv29 to work digital only, and that would in turn leave the lights off, too. But strike 2 and 3 below ...)

(*): I assume that the bulbs are *NOT* burned out, or? false indicator otherwise!

strike 2

strike 3, and out

problem w/ that hope is that the wiring works in analog mode, and is sharing the same path w/ the decoder. You couldn't get the motor to run in analog if the wiring would be bad. However, this does not cover a short in the electric path for the lights, or the motor driver path on the decoder (which is bypassed w/ that analog/dcc jumper), as this will disable the decoder electronics, but normally some parts of the decoder would have bitten the dust, too

I would return that thing, if still under warranty.

/jw

Not necessarily - what type of DCC system are you using? Some systems won't work with analog locomotives. For example, the NCE Powerhouse Pro. You need to test it in analog mode on a piece of track that's hooked up to an ordinary power transformer for model trains.

Frank, Did you read the original post? Or some of the later ones. Clearly, since it ran on analog and the "Er2" response he got when trying to read cv's, It's not an NCE system. NCE will Not run analog, and would respond to his described operation with "cannot read cv".

I thought I read the original post. I got the impression that he put the loco into digital mode, ran it and then switched it back to analog mode before noticing the lights didn't work. And I really don't understand your last paragraph. It seems to be saying exactly what I said, that a NCE PHP would not allow him to run trains in analog mode...

Then you got the wrong impression. The problem is that the loco runs in analog mode but not in dcc mode. Various tests have pretty well established that the decoder is faulty. Keith

Make friends in the hobby. Visit Garratt photos for the big steam lovers.

The decoder was bad in the end. Instead of the dealing with the hassle of shipping it back and paying for shipping, I changed the decoder myself.

I replaced the Atlas decoder with an NCE D13SR that cost me $13.75, and the loco runs MUCH quieter than the other Atlas units I have that came pre-equiped with decoders. In the future I will by Atlas units that are DCC ready and install a 3rd party, quiet decoder.

The installation was straight forward. The wires had to be soldered, and the wiring for the rear lights needed to be extended, but still pretty easy. The only tough part was getting the darn shell off...

Glad to hear you found a solution, but I'm puzzled about 1 thing. What kind of Atlas engine were you talking about?? I've got 4 gp38's and can only hear the sound of wheels on rail when they run. Chooch