PS2 5V Board Problem/Question

I had the same problem with one of my early PS-2 engines.  If I remember correctly, when I asked about the problem I was told I had a bad "MOX board" ( not sure what that is?).  Since I can live without the smoke, I have not bothered to get it fixed. 

This is a well known problem and is addressed in some MTH service manuals. The fix is rather complicated involving rerouting some wires and adding a resistor as I remember. Not for DYI unless you are used to working on boards.

Dale H

I just found another thread but the solution was not shown.  Is there a link to the fix?

Thanks,

Dave

Not that I know of. It is a section in their service manual which was given only to those who took a service course at MTH. Perhaps someone who has it could send you a copy. It might be easier IMO to just rewire the lights to run off track power using LEDs

Dale H

The tach reader is on the same circuit. (blue wire)  I notice that slow speed start up is affected when the smoke unit is on full.

Does anybody have the fix?

Thanks,

Dave

Dave,  You can call the MTH Service tech line and talk to a tech.  He can walk you through the specifics for your engine.  Best to call after 1PM EST.  G

I just purchased a new/old engine with this problem.  I called MTH, they were excellent and advised the fix is about $50.00.  It is complicated and MTH reccomended it be done either by them or a trained tech.  I plan to send the engine to MTH for the fix, however you should be prepared to wait 6-7 weeks.

Brad

David  i was in your store saturday. You have a real nice train store... Thanks for the pins again... My kids liked you..

There was a thread on the MUX board fix at least a year ago, including pictures.

I did not bookmark or save it though.

Anybody have a link to it?

Rod

Rod,

I got the MUX Board fix but I couldn't get a diagram on the 5V board fix.  MTH let me just send that back.  I need to take the service classes.......

Dave

Glad they did   Nice meeting you!

Dave

Quite a while back there was a post that showed a how to fix including pictures.  If that poster reads this could you please provide that information again.

Paul

Go to the Angels Gate HiRailers web page and on the left is listed a MUX board fix that shows a picture with two very faint red lines showing which two grounds to switch. However I don't think this solution is all inclusive. I have an H-10 with this issue but the boards and wires as so tightly packed I did not want to risk a larger problem so I live with it.  I just run with smoke off most of the time anyway.  The smoke is a nice demo feature but it can get annoying after 15 minutes. 

Unfortunately you cannot copy/paste the URL otherwise I would. 

I believe the thread being looked for was started by me over a year ago when I had the same problem with an MTH PS-2 Mikado - dimming lights when the PS-2 smoke unit was in operation. In response, someone sent me a link to a railroad club (not sure but I think in CA) that included a description and a pictures of the fix.  It involved moving and resoldering a wire.  Perhaps this will jog someones memory.  Sorry but I did not save the thread.   

pennsydave

Thank you for the information.  Went right to the web site and there it was.  

Paul

I have a MTH 20-3060-1 SP GS2 with a 3volt board. I'm having what I suspect is a MUX board problem. When running in command with the smoke unit on I will loose the cab, marker and head light. They do not go out immediately, but will after just a min or two of operation. If I turn the smoke unit off, the lights operate just fine.

 My first question is, I know this was a problem on 5volt boards, but does also affect the 3volt boards?

 Does anyone have the correct procedure on how to make this repair?

 As mentioned in a reply above by pennsydave I checked the AGHR website for a repair fix, but I'm not seeing anything regarding that repair.

 I have some old paperwork that has some explanation on making a 4step repair, but I don't know if it covers both 5v and 3v board problems. The first step listed is swapping the royal blue pins, but I'm not sure what that accomplishes as these are tied together on the 3v board.

 Thanks, Scott

Dave,

The first step in fixing this problem is the blue wire in the tender that goes from the board to the MUX board. Take those and swap the psotitons of them. The end that's plugged into the MUX take it and swap it out with the end that's plugged into the main board. Most of the time this will work, if it doesn't then it starts getting to where you have to replace stuff.

I've done a few of these and never had to go any further than swapping those pins. If I can be of any more help my e-mail is in my profile.

Ralph

Scott,

It sounds like something might be wrong with mux board. But I would first check for a short, like something rubbing togethera bare or something like that. Is it drawing more amps than normal would also be something else to check.

That's where I would start.

Ralph

Ralph I will check for a short again. I briefly looked it over, but did not notice anything glaringly obvious. I will definitely look it over carefully.

 Do you know if this problem affects 3v boards as well as 5v?

 Also as I mentioned before I'm just curious what the swap does as there is already a wire(royal blue) that ties each pin together. I'm reading continuity between them so I guess I'm confused as to what the swap actually does.

 Thanks again for your help.

 Scott

Ralph I also realized that I posted the incorrect model number of the engine I'm having problems with. The correct MTH number is 20-3302-1 which is a GS4 not a GS2 as I previously stated.

 The 20-3060-1(GS2) runs flawlessly and does not exhibit the problem with flickering or dark lights.

 As far as current draw the GS4 is actually drawing a little less than the GS2. Both are within acceptable ranges.

 Sorry for the confusion.

Scott,

This was only a problem with the 5volt systems. They corrected in the 3volt boards. As for the swapping of the wires, I'm not 100% sure why it works. I never really asked as it is the first thing to do in our books and when I have done it it worked. The only thing I can come up with is the way components are being fed. Sometimes things just work.

Ralph 

Scott,

Then it sounds like it could be the mux board. Exactly which one it is I'm not sure, sometimes it's hard to tell you without the engien in front of me. I have ones that I know work and then I just swap them out. It's the easiest thing to do.

If you have a tech near you he might have some.

Ralph

Ralph,

 Am I then correct to assume that the engine I'm having problems with would not need a pin swap since it is a 3v board?

 One thing I did notice is that the smoke output on the GS4 is very weak. As far as I know I have all my settings set to max for smoke output. Maybe I need to be looking at the smoke unit itself or a shorted wire in it's harness.

 I will also check on a MUX board. Do you know if they are available from MTH parts?

Scott

Scott,

I never tried it with the 3volt system and I don't think I would as I never saw a 3volt system that has had the same problem as the 5volt system.. Definetly check the smoke unit. Another thing that could be giving you a weak smoke output could be the impeller might be slipping on the motor shaft. Just keep checking everything you can, I know I've missed stuff on the first go through.

I'm not sure if they will sell them to you unless you are a repair center. My guess is probably not. But it doesn't hurt to ask.

Ralph