MTH 30-1129-1 Big Boy with PS1 not working

We had a very similar  post  just a few days ago. Turns out it was  a faulty motor wire in   tether. Maybe try wiggling it. The engine does start up with 2 dings indicating reset which is good.... Marty and chuck posted the fix.  See if I can find the  post hang on......

https://ogrforum.com/...48#78438393743742248

Gregg, thanks very much for the advice.  I went to the link that you provided and found Marty's recommendation:

"Take the engine shell off and look at the 4 pin socket that the tether plugs into.  You have a solder joint on one of the pins that went to a cold joint (no contact).  Touch each pin with a tab of flux then hit all 4 pins with a hot solder iron.  I see this very often.  While you are hitting the pins with a hot iron, keep the plug in the socket."

Well...guess what...that was my problem, also.  I resoldered the four pins on the locomotive tether board and now it is running fine.  I had visually inspected all of the solder joints before, but I could not see any evidence of a cold solder joint.  But, at least one of them must have been bad.

Thanks again for the help!

Russell

Russell, it is hard to make a visual observation.  I usually take my continuity meter and hit the pins one at a time with one probe and then the pad that the pin meets.  Do not put probe 2 on the center of the pin coming to the pad as you will get continuity.  Sometimes you will see a circle around the pin when the joint is cold.  The passing of time has yielded many of these situations.  

I tell folks to hit all 4 pins and you may never have to revisit this issue again.  This is not just a PS1 issue.  I see it in PS2.  Those are not bad to find.  I open both engine and tender and do the following.  Check power and tach for continuity from the 7 pin connector on the board to the locomotive.   Again, the passing of time and engines that are separated from the tender often will often throw you a cold solder issue.   Your continuity meter can in many cases be your repair tech and find problems.

Who told you to get a new chip?  So many other issues to check before the chip fails.  G

G, I talked to someone at MTH and he told me that my problem was probably a bad chip.  He said that the original chips with a printed sticker that says "RK Big Boy" had problems.  He recommended that I purchase a new chip which now has a hand printed legend of RK Big Boy.  I ordered the new chip from the nice people who work for MTH parts.  I have not tried swapping out the new chip with the old one to verify whether the old chip is bad or not.  I do know that with the new chip installed the symptoms were exactly the same as before.  However, resoldering the four pins on the locomotive tether connector did the trick.  It is running perfectly now.

Thanks, Marty, for the soldering advice.  

Just to help future folks, that was the sound of the engine playing chuffs so it was not in neutral.  At that point the solder joints on the engine PCB and a bad wire in the harness become top suspects.  After that, if it does not move in forward, but can move in reverse, it becomes a transistor on the bottom board.

The tech took you at your word it was stuck in neutral, which can be a software conflict or ID conflict.

Sounds it makes is critical to diagnosing a PS-1 engine.  Glad it was simple. G

I must confess that this is the first MTH locomotive that I have worked on.  ...I am a Postwar and Modern Era Lionel guy.  Even though I purchased a new sound chip and that was not the problem, this was a relatively inexpensive fix.  BTW I re-installed the old chip and everything works fine.

Thanks again to all of you guys for sharing your extensive knowledge and experience with MTH trains.

I have a PS1 Reading Camelback with passenger sounds and already have the Steam Ski Train and Union Pacific Doodlebug with similar PS1 passenger sounds.  I believe there were PS1 camelbacks that had freight yard sounds and would like to get one of those chips.  Does anyone here have one of those chips?

Luigi6 posted:

I have a PS1 Reading Camelback with passenger sounds and already have the Steam Ski Train and Union Pacific Doodlebug with similar PS1 passenger sounds.  I believe there were PS1 camelbacks that had freight yard sounds and would like to get one of those chips.  Does anyone here have one of those chips?

 

You should really start your own thread with this question instead of hijack this one.  But to answer your question, just find the MTH catalog number of one with freight sounds and order the chip from MTH parts.

Thanks.  New to this and wasn't sure how to start a topic but that was the answer I was expecting.