Note that this is a PS/1 locomotive we're speaking of. This is a resistor we've talked about before with the same issue.
@CALNNC posted:Well, here is a BCR caveat. I used one of my BCR's in a MTH 2-6-0 with Protosound, that I have no idea what model it is as I do not have the box, it does not have a model # on the loco, tender, or in the manual, there is not even a number on the engine, nothing but A T & S F. That being said, when I put it on the track an applied voltage, it immediately began to smoke, and I don't me stack smoke. A resistor burned up on one of the circuit boards, one in line with the negative lead of the 9V battery clip lead. After conversing with Gunrunnerjohn he ID'd the resistor as a 24 ohm. It looks like a 1/4 watt, but John said it was 1/2 so I believe him. When you buy 2 watt resistors now, they are the same size as the 1/2 watt carbon compositions of a few years ago. He surmised the initial BCR charge current was too much for it. An ohmmeter check showed the resistor at almost short now , and putting in a 9V battery confirmed all loco function were just fine. I checked the BCR for correct polarity and for function, all was well and it worked fine in another locomotive. The short circuit current would be over 3 amps if the onboard regulator could handle it, at what would mean 3 watts dissipating in a 1/2 watt resistor, a very short bit of time and it could handle it, but apparently, this BCR charge up time was too much. The 24 ohm is a form of battery charge current limiting and MTH never expected something like a BCR to come along when they made this engine. This was a .75F size BCR. I don't know if this was a fluke or not, but beware that it might happen in other locos you might try a BCR in. I will now have to open all the MTH locos I put a BCR in, to see if this resistor or its equivalent is present in the leads to the battery.
