Joe, I'm afraid my remote diagnosis isn't going to make your day...although I could be wrong about it.
The buzz...did it go on for maybe three or four seconds before you shut down power and removed the engine? If it was a short that happened, and the buzz continued for more than two or three seconds before you managed to shut off the power, I fear the DCS system's short detector was not able to shut off power on its own, as it should have. Meaning, your decoder probably did the floppy chicken.
You may need to revisit your track wiring, or your DCS system is faulty. I have had my share of derailments and shorts, believe me, but never a fried decoder. One unlikely possibility is that the speaker packed it in at the same time the tender derailed, but I would not bet much on that one.
Will the engine still move, but also just buzzes? Have you tried a reset? If it won't respond to any commands, then I'd say you have little choice but to send it in.
-Crandell
Can you turn the sound off? I have had two engines suck up spikes into there speakers.
I sure know how you feel, I had to send back more than my fair share of $300.00 plus engines to BLI. But, they have a out stand warranty department and made things right.
Cuda Ken.
I hate Rust
dominic cI have a Bachmann Dynamsis. Oh what do you mean by resetting? let me know Thanks Again JC
Okay, I jumped to the conclusion that you were operating your MTH engine with MTH's proprietary DCS control system, their own version of DCC (it isn't DCC, but you can control their engines using DCC, as you are doing with your Dynamis.) Gotcha now.
As far as I know, all decoders can be reset, or have their factory default CV settings restored to original. This includes the DCS decoders, which your engine should have. In DCC, some decoders, most of them in fact, require CV8 to be programmed with a value of "8". The QSI decoders have a three step reset with three different CV's.
Sometimes the chips get a bit scrambled, say during a short in the rails, and when you correct the fault and restore track power, the engine behaves differently...even in weird and scary ways that make you reach for the track power switch really fast. This is when you do the reset so that you can start over. If the decoder won't reset normally, following instructions, it usually means factory service.
My question still, though, is why didn't the Dynamis sense that there was a short and cut power inside of the 4-100 millisecond it should have taken to sense it. I guess it has something to do with where the short took place, but it is beyond me to explain it. Maybe Randy Rinker or someone else can explain it?