Lionel Legacy (Older) Fan Units alive when power comes to the track

If you have either a TMCC CAB-1 or LEGACY CAB-2 remote pressing AUX1 + 8 will shut off the smoke units. Pressing AUX1 + 9 will turn them back on.

Just make sure the selector switch on the locomotive is in the "SMK" position as the remote will not override it if the switch is left in the "NO SMK" position.

Thanks.  I have a legacy remote.  I know how to turn them off from the remote, but wondered if it was a programming issue, and if there was a way for them not to come on when I powered up the track, unless I hit Aux 9 of course.  It seems that it was an issue with the earlier units.  I thought mabe there was a fix.  

The above post are a little confusing.  If you turn the smoke switch off does the fan stop?  If so, but when you turn smoke off via Command only heat goes off and fan stays on, that is probably because the AC to the fan is not through the AC REG that controls the heat element.

Your smoke unit is semi smart.  The AC power to the heater goes through the ACREG which is controlled by serial data from the R4LC.  Normally on semi smart the power for the fan comes from the Heater element AC power and is rectified and changed to 5VDC for the fan.  Most likely that portion of the circuit receives AC power directly and bypasses the ACREG.  I would need to see how it is wired, but if the smoke unit is modified to let the ACREG power the fan circuit too, than when you command smoke off and the ACREG turns off AC to the smoke unit, the fan will stop too.  G 

It is an issue with some earlier Legacy units and the best idea is to turn off the smoke via the CAb1 or 2 and then shut down the engine. I have done that and so far that seems to be the best work around to the problem.

Thanks guys.  I will experiment to see what works or doesn't work.

Yes. If you turn the smoke switch off, all is off (fan and smoke unit).  When the smoke switch is on, and you power up the track, the fan comes on.  I can, from the remote, turn it off.  However if I shut down the power and re-power up the track, the fan starts up.  Hmmmmm.   I will double check to see if this happens each and every time.  Lately I have just been leaving the smoke/fan units off from the smoke switch.  Will advise.

That is an interesting twist which means fan is controlled too.  I would call Lionel and ask.  Some ACREG became obsolete, maybe there is a revised Code ACREG that will fix this.  I think ACREG go for $30 plus shipping.  G

They still do it Marty.

Marty, I think he understands that, but he is looking for a fix.  If Lionel resolved it with later legacy, I am sure he can too.

The smoke unit on that model is pretty simple.  G

It's most likely resolved in later units by changes to the code in the integrated electronics, he's not going to make that "simple" fix in the older modular board set.

The earlier TMCC M1a had an issue where the smoke unit stayed on even after the engine was shut down. It only turned off when the power to the track was turned off. It did respond to AUX1 8/9 though.

John, That is not true.  This is a simple smoke unit, without integrated electronics.  In R4LC, the smoke triac on the R4LC is always on.  The serial data to the ACREG controls the AC power to the smoke unit.  In this case I think they cut the trace on the smoke board that powers the fan from the AC input to the heater element.  Then sent a separate AC power to the fan circuit.  Either they stopped doing that or used a newer AC REG that turned AC off to fan.  Hence seeing unit and determing how it was done.

Later when they went to Smart Smoke you got to integrated electronics.

I still think this is a simple fix once you can see how this is wired.  This is the dumb smoke unit with no chips, just a 5V regulator, diode and 2 caps.  G