Sound Went out on a PS2 Engine

Could be a lot of things, but it might be a bad speaker,especially if it is a 4 ohm one.

Dale H

Interesting that in the parts list for this engine it lists a 16ohm speaker, but the actual speaker in the engine is a 4ohm. Now if I could just find a spare speaker to test. I know there is one around here somewhere.

What is the engine and do you know if it has a 3V or 5V board?  The 16 ohm speakers are the ones causing us problems.

Is this an engine you purchased new or from that evil place.

What is the product number of the engine? Something is not right here, if the parts list says it should be a 16 ohm and you have a 4 ohm in there, someone replaced it with the incorrect speaker. What type of battery is in it, a 9V type or the AA battery pack?

Product # is: 20-2536-1 It does have the AA type battery pack.  When I bought the engine I did not have DCS, so I do not know for sure that it had not been run before, but it sure did not look like it had been.  I got DCS a few months after buying the engine and the hours and miles seemed right for a new loco that I had been running for that amount of time.

For the parts list I went to the MTH web page and put the product # in, that brings up my engine. Then I clicked on the little gear icon and that takes me to this page: http://www.mthtrains.com/sites...loded/20dl12951e.pdf

The first page in that document does not list my product #, but it is for SD40-2 engines.  Maybe that is not the correct parts page for my engine. 

The 4 ohm speakers are the ones that fall apart at least on my engines. If it has a 4 ohm replace it with one or more speakers with 4 ohms impedance,if that is what the original design called for. If it originally had a 16 ohm speaker and it was replaced with a 4 ohm one the amplifier section of the board would likely be damaged in short order. If it calls for a 4 ohm speaker and it is replaced with a 16 ohm speaker the board would not be damaged but volume would be very low. All my stock PS2 16 ohm speakers are rated for 1/2 watt,not 3 watts as specified in the SD 40 parts list linked..

 After market speaker replacement is discussed here

https://ogrforum.com/d...ent/3400749735614071

The 4 ohm $1.25 replacements from Allelectronics look as good as the stock ones I have removed in quality. I have not got around to trying them though. If space is an issue I will use them. However space allowing I have used the more expensive Madison sound replacement ones linked. Using it, sound fidelity,especially low end range is much improved but this speaker may not fit in all applications. 

Dale H

I think I figured out why the parts list calls for a 16 ohm speaker and I have a 4 ohm in there.  If I remember correctly 2004 is when MTH was switching over to the 3V system, my engine is a 3V system but it looks like the parts diagram that is linked above is from a 5V system.  Now I just need to find the correct parts list for my engine.  

  I think my speaker is probably fine, hopefully I will just have to check all the connections and wire a little closer to find the problem.

Thanks everyone for helping on this.

Barry, as you know I have 100 plus locomotives with 4 ohm speakers and have never had an issue.  Am I missing something?  All my 16 ohm locomotives get speaker replacements when they come to the bench for any reason.  The 16 ohm speakers are great magnet donors to help keep paperwork posted on the steel door next to the workbench.

Marty,

You'll get no argument from me.

Funny,  I just repaired a PS2 5V system on a gentleman SD-60.  It just died on him.  No operation in conventional, no sound.  Used DCS and it ran, but no sound.

So I opened it up and replaced the 8.4V battery, which actually had a little swell to it.  No leakage, but the battery terminals had some internal corrosion.  Battery harness connector was fine.

Ran in conventional and DCS but still no sound.  So I dropped the fuel tank to inspect the speaker and was surprised to find a 4 ohm speaker.  Removed it and it was reading open.  Replaced with a 16 ohm and sound was restored.

Now I need to go back to the owner to see if this was worked on before.  I know he bought it new.   G