What regulator did Lionel send me?

@Randy P. posted:

I want to replace the AC Regulator in my brand new but 12 years old 6-11117 loco. The smoke unit runs but does not respond to Legacy CAB 2 commands for off/low/med/high; it always sputters just a whisp (assuming the loco smoke switch is on.)  Right out of the box. I ordered the correct replacement part, but Lionel sent me something slightly different.  My loco is torn down but I can’t get them to respond to me (it’s been a few days and one call and two emails.)

Photo from their parts listing that I ordered (with 2 black, 1 brown, 1 red wire plus a transistor hanging off).  This matches what’s in my loco:

Photo of what Lionel sent me (note extra wire):

I marked it S03 when I got it, before I realized it was different. Lionel doesn’t list any other regulators that look like this.

Does anyone recognize this?  Thanks!

Looks like the 8volt AC regulator board that I took out of my B&O F3 #6-14569. It’s used to run the 8ohm smoke unit

Here’s the front and back of the wiring diagram showing the 5 wires.

I had similar concern on a regulator that had an "extra" wire.   See my post:

https://ogrforum.com/...ke-unit-troubleshoot

Steims, thanks so much for your link. I find the last comment from gunrunnerjohn especially interesting: “Note that on Legacy, they finally started bolting the triac to the frame to try to keep it from cooking.  They don't cook as often, but the Legacy ones still fail.”

It sure sounds like they sent me an older version of that unit (I’m guessing the triac is wrapped inside the heat shrink tubing.) Which is unfortunate because I’ve had exactly the problem they were trying to prevent with the upgrade found in my loco. Ugh.

The "extra" wire is simply a second ground, just ignore it.  Also, make SURE you don't mix up the black, brown, and brown/black stripe wires!  Their wiring colors leave something to be desired, why in the world they didn't make the brown/black stripe wire some other obvious solid color is a mystery to me!

Thanks gunrunnerjohn, and also for the suggestion to splice rather than try to rebuild the connectors.
I’m going to hold off on the repair and call Lionel again on Monday as it is frustrating to have to revert to a version of this part that is more likely to fail than the one in my loco which failed immediately (I presume.)

Oh, goodness yes, just splice them in!  FWIW, that's how Lionel replaces them as well.  Sadly, the AC regulator is a very trouble-prone piece, I have bunches of them that have failed in a box.  I even get new ones that don't work from Lionel!

Say, gunrunnerjohn, have you ever tried to repair these AC regulators?  Do you happen to know which part most commonly fails?

I just took a closer look at the one that came in my loco, and suspect my problem was simply related to poor workmanship -- two of the wires were shorted together.  And mine didn't work out of the box.  See attached photo.  I separated the wires but the unit still does not work -- but it got me thinking that it might be repairable -- although failure due to a short might blow a different part than failure due to heat.

Your thoughts appreciated.

I thought about it, but I believe it's the microprocessor that loses it's marbles, and without the code to re-FLASH it, that's a loser.  My reasoning is that the most common failure mode is they start to lose function and gradually get worse before they quit working altogether.

FWIW, for a few extra bucks, you can pickup an SFC1 and those seem to be quite a bit more robust. You can add whistle steam with those too. That said, they’re a bit larger.

I'm surprised that this didn't take out more than the regulator!  The serial data is shorted to the smoke unit AC heater voltage!  Black with brown stripe is the smoke heater, brown is the serial data.

@gunrunnerjohn posted:

I'm surprised that this didn't take out more than the regulator!  The serial data is shorted to the smoke unit AC heater voltage!  Black with brown stripe is the smoke heater, brown is the serial data.

I guess now we know why these are failing frequently!

I finally heard back from Lionel today.  They are going to mail me the correct items.

I hope after all this, a new AC Regulator solves the problem! ;-)

S03 code is correct for low/med/high adjustable smoke. You can take the heat shrink off and mount the triac to the frame, with an insulator piece and insulated washer. Sure you have enough smoke fluid in it? Most times when the regulator fails, its full on smoke.

Chuck, I wrote the S03 on the heat tubing before I realized it was the wrong part - it's not an S03.  It might be an old version and now that I don't have to send the "wrong" ones back I'll cut the tubing and see if the board is similar.  It might be the same as the S03 but with the triac tucked in and a spare ground wire that can be cut - that would be nice!

Regarding smoke fluid, yes, saturated.  I've got the loco apart and took apart the smoke unit and disconnected one side of the resistor to confirm it's 8-ohms, and while I was at it I took out the wick and pulled it apart more and fluffed it back in.  No need to replace as it's brand new with just a touch of brown from my testing.  The resistor is getting some voltage, but not enough to produce more than a polite suggestion of smoke.

I plan to post a summary of everything I've learned once I've got the new unit installed and *hopefully* working.  But it will be a few weeks.

OK, Lionel has sent me wrong parts to me also.

FWIW, I got a bunch of the S03 regulators, and they all appear to be defective.

They start out with an output like this, and the smoke starts as normal.

A few seconds after turning the smoke on, the waveform slowly, it ends up like this within 10-12 seconds.  The smoke vanishes, and yes, I'm using the proper 8 ohm resistor and all the leads are tight, continuity through the wiring is perfect.

Since four of them do this, it's clearly not one defective unit.

As a note, all of these are clearly used, not a truly brand new one in the bunch.

According to the parts listing, those locomotives use a 6 ohm smoke unit. Unless it's a typo...

https://www.lionelsupport.com/...tive-only-6101117001

https://www.lionelsupport.com/...SSEMBLY-6-ohm-ANALOG

@rplst8 posted:

According to the parts listing, those locomotives use a 6 ohm smoke unit. Unless it's a typo...

https://www.lionelsupport.com/...tive-only-6101117001

https://www.lionelsupport.com/...SSEMBLY-6-ohm-ANALOG

A long time ago Lionel recommended replacing any 6 ohm resistor with an 8 ohm resistor as the excessive power was killing the regulators.  An 8 ohm resistor is the correct resistor to use in any locomotive with this regulator.

Yes. But I wonder if the 6 ohm resistor would work better with the lower voltage your finding with those regulators. Maybe the problem with the 6 ohm ones was actually a bug in the older firmware that wasn't backing down the voltage.  Just an idea. 

I've already tried the 6 ohm resistor, there was no change.  There simply isn't enough power to produce smoke with whatever resistor I use.

Just as a follow-up, Lionel sent me two correct AC Regulators code S03 that matched the one in my loco that was not recognizing Legacy smoke commands.  Tonight I replaced it and now my loco smokes like it should.  So thanks to @gunrunnerjohn for pointing me to that assembly as the likely culprit - it was!

I wish i could repair my old one, but John suspects the likely failing part is the 8-pin surface-mount chip labelled (beneath the S00 label) "MQ4CE RMGKFm", which he says is a microprocessor with custom-flashed code.  And by the way, I don't know if there is any significance to the fact that my old part had a "S00" sticker on the 8-pin chip (i.e. not "S03".)  I looked at the new part that Lionel sent me and that chip has a sticker labelled "S03."

Alas, the 2N6073BG triac is easy to get and easy to replace -- so hoping against hope and with no reason to believe this would be the failing part, I did order a few.  They bolt this thing to the frame so I'm assuming it can get hot.  The next time an S03 regulator goes on one of my locos, I'll try swapping in my bad one with a fresh triac.  Why not?

Anyway, I wanted to let everyone following this thread know that swapping in a new S03 AC regulator fixed the problem of my 6-11117 loco not recognizing Legacy smoke commands.