Reset chip on Diesel

[mishmash64]

Hi everyone, I'm new to cv values and resetting chips on Diesels. I have been using railmaster for about a year now and have written deceleration / acceleration values but thats about it. My Diesel, a Dapol class 26, has stopped working two days ago and all the cv values had disappeared. I tried writing the values again but it keeps coming up " error repeating", sometimes it works most often it doesn't. My programming track works fine as I have tested it with another Diesel.

What are my next steps?

 

Thanks in advance

[jane1707819582]

If it is a dapol imperium decoder ,A value of 4 to CV 8 resets the decoder .

[Chrissaf]

Clean the wheels of the loco [particularly where any pickups touch them] and check the pickups [if the loco uses them] for correct alignment and touching pressure.

 

Your reported observations seem to indicate that the electrical path between the track rails and the decoder are intermittent.

 

Possibly a broken wire inside the loco that is just touching and giving intermittent connections.

 

[mishmash64]

Hi, i have reset the decoder and tried again.  It goes through the first 20 or so instructions and always seems to get stuck on the re-mapping section, keeps coming up error-repeating and can not verify after a few goes. I'm no experienced enough to open her up and know what to look for.

Help please!

[96RAF]

Is it identifying your decoder correctly - at CVs 7 and 8. If not, before you start reading simply double click CV 7 and pick your decoder from the list. If its not listed then its not in the RM database and RM will not know which CVs to read so it picks them all and likely fails.

This of course does not stop you writing new values to the decloder for any supported CV using the pencil icon not the tick which is the read instruction.

[mishmash64]

Hi, yes it is.  It reads all the cv's through to the remapping section at numbers 40 to 48 but then stops somewhere in between these numbers

[Chrissaf]

Use the range setting at the top right of the screen to limit the range to read to just the main important ones. Say CV1 to CV15 for example. Then it won't ever reach the problematic ones and stall.

 

As Rob says, there is absolutely no mandatory reason to read any CVs if you know what CVs and values you want to set them. Miss out the reading part all together and just go straight to the writing tasks. In RailMaster any CV value that you set by writing to, is read back anyway to confirm its value as part of the writing task.

 

In fact with RailMaster, when faced with a problematic decoder it can be the act of trying to read the decoder CVs first that can be the cause of an issue. I suggest, you close and restart RM to get a clean starting slate. Then go to the CV writing screen and DO NOT attempt to read any CV value. Just write the CVs you want to write. DO NOT try to read them back manually, just close the CV screen and put the loco back onto the main track and test. This method has worked for others on this forum with problem decoders.

 

[mishmash64]

Thanks for your reply Chrissaf.  I will try running through the first 15 cv values, but the rest I dont know what values to set them. I assume that I do need the rest of the cv values?

 

[Chrissaf]

Follow the guidance in my last paragraph about not reading any values and going straight to the write CV task and use that guidance to factory reset the decoder. That will set all the less critical CV values, then all you need to do is set the DCC address and test, possibly tweaking CV2, 3 and 4 as appropriate. The factory reset default values are actually stored in the decoder, so it is really not necessary to identify the decoder in RailMaster which seems to be part of your issue. Sometimes I find RailMaster is too clever for its own good and over-complicates matters. I find I get better results from RailMaster by just using its basic functions without the fancy frills [i.e the built in data-bases] that seem to cause more issues than they solve.

 

Normally for most decoders, the factory reset is writing a value of 8 to CV8, but also note Jane's comment in her reply.

 

Please read TIPs 1, 2 & 3 in my TIPs page regarding extricating your text cursor from the buff quote box.

https://www.hornby.com/uk-en/forum/tips-on-using-the-forum/

 

[96RAF]

If the decoder is reset then as Chris says it is loaded with a set of default values for all supported CVs, including setting the address at 03, thus you only need to write to those CVs you want to change a value for. All else you can leave at default.

[mishmash64]

Hi, thanks for your help. I have successfully got all my cv values confirmed by doing it 10 at a time. However, when I put the diesel back on track I have front lights, but not rear lights and I can hear a slight purr but no power forward or backwards. So I guess it is a fault with the actual diesel and not the decoder?

Any ideas please ?

[96RAF]

If you have DC running enabled in CV29 put a 9v battery terminals directly across the wheels and see if it runs. If not unplug the decoder and put the blanking plate in and repeat the test.