No Reverse

Orgiva

Orgiva

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Quick question, I hope. Is there a CV value, which if set, will prevent a loco going in reverse?

I have just received a LGB rack loco with a factory installed decoder. I've managed to read the decoder with a Massoth Service Tool set to 'LGB Onboard gross ME v3.4' and changed the loco address successfully. It drives forward, the lights come on, when switched on. But when I put it into reverse, the lights come on but it doesn't move. This is also the case when I use analogue DC too.

Any ideas?
 
No such CV that I know of. More likely the decoder motor outputs are partially damaged.
 
Sounds likely Nick - or a mechanical jam in one direction only.
 
If it won't reverse in analogue DC, then it sounds possibly mechanical (although I'd go for marmalade).

Back to basics - remove motor and test
Replace motor, but test power to motor contacts rather than through the decoder

Scratch head

Ask other people for ideas :nerd::nerd::nerd::nerd::nerd::nerd:
 
Unlikely (but not totally impossible) that a mechanical problem would cause an absolute lock-up that won't even clear slightly if run forwards then reverse. With a mechanical problem in a loco with rods it's usually the motion locking at one point of the wheel revolution due to bent rods/links, a wheel out of quarter, or a split gear.

Is there any motor buzz or hum at all when you try and run in reverse? If not then I still reckon it's a failed decoder output. I had a Lenz Maxi go the same on me a while back. One of the output FETs had blown.

Does "factory installed" mean it's a plug-in decoder done by the factory, it is it an on-board decoder that's part of the main circuit board? If the decoder is removable, unplug and set any dip switches back to analogue mode, and try that?
 
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Thank you for the replies. This is a LGB 23460, brand new, out of the box. As such, I really don't want to start pulling it apart. If, as it seems, it's the decoder, I'll have to send it back.

There's no motor hum/buzz when I try and run it in reverse.
 
If it is not too inconvenient, I would certainly return it,
 
If it is brand new.. Does it have an MFX decoder in it?
If so, try turning off MFX support.
 
Did you happen to notice if it worked in reverse before you changed the address? What did you change to address to?
 
Unless your supplier is in a different country - return it - how else do manufacturers learn.
 
The shop, in Dortmund, has very quickly agreed to reserve another one, which they'll send out on receipt of this crocked one. I bought it through ebay, which seems to keep vendors relatively sweet when things go wrong.

Arthur, I've done a full read out of the decoder CVs using the MST I have. Can you let me know what I'll gain from doing as you suggest? Thanks.
 
excellent result
 
FYI the LGB 23460 Rack loco has a LGB Large Onboard decoder (made by Massoth - hence the Manufacture code of 123).
 
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