30-1834-1 steam engine no chuffing in engine

I had a similar issue and the problem stemmed from 6 pin wiring harness in the tender. I unplugged it from the tender board and the drawbar connector and swapped them.

I had an engine with similar problems but only when rounding a turn:

Thanks to @gunrunnerjohn who posted the tether wiring diagram:

This thread touches on the problems you are experiencing and you might find some help here: https://ogrforum.ogaugerr.com/...ne-w-proto-sound-3-0

In this thread @Jon G had a very useful tip that help solve my problems:
Repeated connecting/disconnecting of the drawbar enlarges connections inside the 6-pin harness.  Swapping end for end sometimes fixes it because the harness connection in the board doesn’t move.  I used to disassemble the harness wire by wire and tighten the  “clamp” that grips the pins on the drawbar.

H1000 thanks for the info, I am now looking at the tender harness . I found the green wire has a 4.6 k ohm resistor in series between the ends of the six pin connectors .Is that the correct value ? All of the rest of the wires check out for continuity, now I am looking at the boiler harness for continuity. Stay tuned !

FredB

@FredB posted:

I found the green wire has a 4.6 k ohm resistor in series between the ends of the six pin connectors .Is that the correct value ?

Yes, a resistor should be there but 0.470K or 470 Ohms. Also hint- that is the serial data line carrying the chuff back to the tender board (along with other data). I just measured a harness on hand and confirmed 470 Ohms

I have seen bad solder joints under the heatshrink on that very resistor before.

https://www.mthpartsandsales.c...shooting%20chart.pdf

Again, key here, there are 2 serial data lines. One goes from the tender to the boiler board to send the commands since the tender board is what actually reads the DCS commands and makes the sounds. The return line from the boiler board carries the chuff and possibly other status data back to the tender board.

So yes, possibly the wrong resistor installed? That might throw off the signal and never pass chuff signal to the tender.

Thanks guys , I just happen to have a brand new harness and that measures 462 ohms , so the old one is out of range , way out at 4.7 k ohms ,

now mind  you this engine is brand new from the dealer ,never been run except for testing by me and the client . The pictures of the old one shows 47 ohms yellow, violet ,black ,brown, @1% ,fifth band is brown as well. WAY out of range !

Thanks guys , a 470 ohm did the trick everything works fine except the lights they are plug into the wrong sockets not too hard to figure out .

Fred

Where do you see a second data line?  There is only one data line labelled draw bar.  Interesting on the resistor, I think they have had issues on certain runs early on.  And very early no resistor.  That can cause the tender board to be damaged.

I would have guessed a faulty tach reader.  Classic symptoms.   Did it have speed control when running?

The boiler board controls the smoke fan, so it is weird that the data resistor effected speed control and smoke.  Chuff I could see since tender does that with the data from boiler board.  Weird.  G

Hi G

on my engine I first changed the boiler board and the tach pick up , no change no chuffing or smoke while moving , it smoked at idle ok ,speed control was ok, when I changed the resistor from 4.7k to 470 ohms everything worked fine . Lights were screwy though . Plugs were connected wrong
Fred B

Up date engine works fine with proper lights and chuffing , customer very happy .

Fred

@Vernon Barry posted:

Yes, a resistor should be there but 0.470K or 470 Ohms. Also hint- that is the serial data line carrying the chuff back to the tender board (along with other data). I just measured a harness on hand and confirmed 470 Ohms

I have seen bad solder joints under the heatshrink on that very resistor before.

https://www.mthpartsandsales.c...shooting%20chart.pdf

@FredB posted:

Thanks guys , a 470 ohm did the trick everything works fine except the lights they are plug into the wrong sockets not too hard to figure out .

Fred

@FredB posted:

Up date engine works fine with proper lights and chuffing , customer very happy .

Fred

This is the way this forum shines.

Great solution and results .