Charged batt overnight, blows horn or bell continuosly depending on polarity without touching buttons, has steam sounds, no movement
headlamp blinks when pushing horn or bell buttons, otherwise it's off.
Thanks for your help.
John
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Any chance you are using a CW80 Lionel transformer?
No I'm using a MTH Z-750 transformer
Test battery? maybe it's gone.
Engine could be locked in neutral too.
If battery tests good do a conventional reset.
Do other engines work fine with this transformer? If so, the engine could have a pinched motor lead or PV line that is inducing the DC offset onto the chassis ground causing the whistle/bell. Since this is a 5V board it could also be going or is bad. G
The Z-750 controller is a chopped wave controller, it could have a problem that is putting the DC offset on the rails. If you try reading the transformer output with a multimeter set on DC, do you get a non-zero reading?
Hi Gunrunner John:
You were right, I tried a friends Z-4000 and the Loco performs fine.
Thanks to all
John
Hi Gunrunner John:
I have a Caterpillar set with PS2 that came with a 750 and have not had this issue. Is there a subset of PS2 engines susceptible to this? Also, I use this transformer to power my DCS (auxiliary pwr source) TIU and my z4000 for the tacks, I cannot see how this would have any affect the TUI function or engines but could it?
...cannot say how many times your posts have help me understand this technical aspects of this hobby so, gratefully, thanks for sharing your knowledge...again.
I would have guessed this was narrowed down to just that engine. Shows me!
Obviously, this would only happen in conventional mode. The reason I bring it up is I see an occasional engine on the bench with my Z750 powering it that will blow the horn or ring the bell spontaneously. It's a pretty well known issue with chopped wave transformers. Like I said, there could be some minor issue with that particular Z-Controller that causes the problem.
It was the reason I asked if other engines do this. If the answer is yes it points to transformer. The Bell or Whistle button can have a leaky capacitor that makes it act like the bell or whistle button is pressed. This can happen to the Z-4000 also. But we also have seen Z-750 that just cause weird stuff, so sometimes the control board goes bad. G
I have a z750 controller that went in the trash pile. For some reason that's the only one that gave me issues. My Z1000 seems fine.
The design of the two are identical, I suspect there is just some component tolerance that causes a DC offset in some of them. Probably a few get enough to occasionally set off the horn or bell.
