Bachmann Branchline DCC Ready

[OffTheRails]

I have recently attempted to fit decoders to DCC ready Bachmann Branchline locos, a six pin and 8 pin decoder.

 

The decoder was a reputable brand and fully tested before the installation, the locos were both new and operated in DC mode.

 

On installation the decoders read back to the control unit but failed to operate the loco.

 

Has anyone had similar experiences or perhaps can make suggestions as to my problem?

[Oldddudders]

I have fitted dcoders to several such locos in recent months without issues. Not all locos are the same - which models? 

[34theletterbetweenB&D]

3 hours ago, OffTheRails said:

...On installation the decoders read back to the control unit but failed to operate the loco...

Does this mean firstly that you tested for a successful installation on programme track and successfully changed the address? Did you see the loco 'twitch' slightly as the new address installed?

Secondly the failure to operate. Was the loco then on normal DCC track supply? (It won't run on a low current programme track.)

 

Typically failure to operate on DCC is a symptom of no current reaching the decoder. Any of a broken connection to the rails, dirt on rails, dirt on current collecting wheels, poor pick ups on loco are common causes.

 

I would suggest switching off, checking over the DCC system connections, cleaning the rails, switch on and try again.

[Art Dent]

8 hours ago, OffTheRails said:

The decoder was a reputable brand and fully tested before the installation,

 

Hi,

 

How did you know the decoder(s) were good?  What (or who) tested them and how?

 

I'm not suggesting the decoders are bad but 34C makes a good point that if you have used the programming mode to check read-back of the decoder(s) and they read OK, you need to leave programming mode in order to operate the loco(s).

 

It would also help to know which DCC system you are using.  Some of your earlier posts suggest a Roco Z21??

 

The Z21 has THREE power connections on the back of the unit next to the DC input socket.  One is labelled 'Sniff BUS', the middle one is labelled 'Prog Track' and the one closest to the DC input socket is labelled 'Main Track'.

 

Which of these is connected to the track that you are trying to drive the loco on?

 

Regards

 

Art

Edited March 2, 2019 by Art Dent

[OffTheRails]

Thanks guys. I used and NCE Power cab and read the Manufacturer ID and decoder type in program mode. The  decoder was then tested  using the ESU decoder tester. I attempted to run the train in operation mode.

 

Back to the drawing board!

 

OTR

[johnb]

This nsound like a common  NCE controller confusion in that you need to be sure whether the address set is short or long. for example 1 as short or 0001 as a long one. Iif the loco won't respond to say 1 then try 0001 , if it's a 2 digit address try say 33 (short address) or 0033 ((long address).

 

It's all in the setting up when the controller asks which you want as active, you can set both short and long but can only have one active!

 

John

[Nigelcliffe]

"Reputable brand" means nothing, an awfully large number of brands have produced the odd turkey, and there are some ancient designs still kicking around. 

 

To help those trying to provide a diagnosis, please post exact make/model of decoder (as far as can be determined from CV8+CV7, and any other maker specific CVs for identification), plus loco address, CV29 and CV19 values.   Then the differences might be possible to explain. 

 

Six-pin decoders can easily be put in backwards, and then won't operate the motor.   But might still read back, depending on loco wiring and decoder in question.