Spectrum connie w/DCC troubles

[Michael J. Caboose]

I've got a Spectrum Consolidation with DCC on board. I've used it about 4 or 5 times with my Bachmann EZ DCC command system, until I smelled burning electronics from the tender. I haven't had any troubles with my other DCC equipped locomotives. I suspect a defective decoder. I contacted Bachmann's service center last week, other then asking about what system I was using, I haven't gotten a response. Is this as simple as getting a new decoder and replacing the old one? If so, I might as well do that but I'd like to maybe get some answers answers. I love the locomotive, but it was new and I don't want to shell out for a new decoder if it can be sent in.
Thanks

[Yampa Bob]

First you should remove the tender shell and check all the wiring, wheel pickups, pc board and decoder for sign of heat damage from shorting or other problems. Also be sure the tender trucks have not been rotated 180 degrees from their correct position.  I posted a diagram in the following thread:

http://www.bachmanntrains.com/home-usa/board/index.php/topic,6698.30.html

The DCC on board version is shipped with two small wire jumpers, and instructions how to install them. I would remove the decoder,  install the jumpers and try the loco.

If you determine the decoder is the problem, then you have a couple of options. Bachmann has a great warranty, but it requires communication, shipping charge and waiting.  However they will repair or replace at no charge if within the first year warranty period.

The other option is to replace with another Bachmann decoder, or use a Digitrax DH123P.  If DH is used, then the capacitor(s) need to be clipped from the board.

[Jim Banner]

There are two other things that you must do before you can definitely say the problem was caused by a defective decoder.  One is to measure the stall current of the motor.  It is possible that your locomotive has a faulty motor that overloaded the decoder.  If you are unsure how to measure stall current, please ask.

The other 'must do' is to check that the motor connections and light connections are isolated from from the pickups.  You can do this by removing the dc jumpers from the decoder socket and plugging in some fine wires instead (use wires no bigger than the jumper wires to avoid damaging the socket!)  Then use your ohm meter to measure resistance between appropriate pins (it should be infinite.)  For pin assignments, click on the link below.

http://members.shaw.ca/sask.rail/dcc/2-8-0/index.html

When you do the checks suggested by Bob, you may find a reversed truck and signs of over heated wiring.  In this case, it is possible that what you smelled was the wiring and tender shell over heating and not the decoder.  A reversed truck does not normally destroy a decoder but it may reprogram some of its CVs.  A damaged decoder often melts a hole in its shrink tubing cover before it quits completely.  I noticed you didn't mention any melting, so maybe there is hope for it yet. 

Once you have completed all the checks, you could try the decoder again.  Consider that the address has changed and acquire it with your E-Z Command using the instructions for acquiring a locomotive with an unknown address.

[Michael J. Caboose]

Well, i've done all the trouble-shooting, thank you both for the suggestions and the directions on how to proceed. I've come to the conclusion that the decoder has burnt out. It's still in warranty, as I only had the locomotive for about 3 weeks (sent in the card as soon as I received it). But I don't think it really matters, as this gives me an excuse to put in a sound decoder. Thanks again guys 

MJC

One more thing. Since I think I'm going to add sound, which sound decoders fit? I'm only a bit worried since the vanderbuilt tender it came with looks rather small. Any suggestions to plug-n-play sound decoders?

[Yampa Bob]

From several posts on the forum, the general consensus is to remove the board and hard wire a Micro-Tsunami, with the speaker mounted under the coal load.

The standard Tsunami is plug and play with an 8 pin adapter harness, but the vandy tender may not have sufficient room for the decoder.  The 8 pin universal plug is available to solder onto the Micro wires, making it also a plug and play if you prefer.

"RichG" has done many installs, and will probably be in to give you more information and pictures. 

If the decoder did "burn out" then, as Jim suggested, you should do a stall test on the locomotive.  Doing this requires an inexpensive digital ammeter to determine the current draw while the loco is "stalled".  This should be done on DC power, either on your layout or a separate test track.  Typically the stall current shouldn't exceed about .6 to .7 DC amperes, for a one amp decoder. 

If you don't have a digital multimeter (DMM), suggest obtaining one, possibly two as it is helpful to monitor the voltage while doing the stall test.

http://www.multimeterwarehouse.com/dt830bf.htm

Were you able to get the loco running on DC? If so, be sure it is well broken in, with no binding, slugginess or motor overheating before installed the decoder. I would suggest repeating the stall test after break in.

Stay tuned, more help is on the way.

[pdlethbridge]

If he has a connie it should be light steam. They have a Baldwin Consolidation listed as one of the sounds that particular tsunami comes with.

[James Patterson]

for some reason burning smells from bachmann decoders are typical for me, my daylihgts fried about 2 months after i got it, and a friend decoder in a model 3751 also made a burning smell and acually melted the plastic around it in the tender. maybe its a defect IDK, but i know i'll be replacing mine sooner or later...

[Michael J. Caboose]

Well I put the jumpers in place of the decoder, and she runs just fine on DC. This is alright for now. I'm still looking for a speaker that will fit the vandy tender though.

I might plug in the decoder back into it, and see if maybe it might work again, but like I said, it doesn't matter much as I'm gonna add sound.