Gaugemaster BP DCC27 omni decoder problem.

[Andy 321]

Hi i fitted a Gaugemaster BP DCC27 omni decoder to a DCC ready locomotive all was working well lights working fine ran locomotive on dcc and DC fine next day the lights not working and the installation was damaged the locomotive still runs fine any ideas what caused the issue also if I use this decoder to hardwire another locomotive can I use the additional wires for lights new to DCC. 

[96RAF]

The most important thing is to determine why the installation failed and which bit of the decoder is damaged.

 

If you say the lights don’t work on the one loco then it is likely they will not work on another loco. You will not be too impressed if you go to the bother of hard wiring to then find out it is duff.

 

Also if you put a new decoder in the first loco and it was the cause of the problem it is likely to damage the new decoder.

 

This is where a multimeter and a decoder test rig are worth their weight in gold. Also use of a programming track with its low potential will generally show up any installation issues and prevent any damage to a decoder. If you cannot afford a £40 commercial tester like the ESU 5190x device (see photo) they are fairly easy to make. All you need is a motor, a decoder socket, a few leds and suitable resistors all mounted on a bit of veroboard. See here for one I made earlier - http://www.halton96th.org.uk/article4.html

 

ESU decoder test rig

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[Andy 321]

Thanks for your reply regarding programming track what should I look out for, I have a multimeter any advice on part's to test. 

[96RAF]

Which controller (and firmware revision of known) are you using as some effectively program at full track potential, typically those with only a TRACK output, such as thenSelect

 

Othe controllers such as Elite and eLInk have separate TRACK and PROG terminals and the latter output is at the safer low potential output. This low current and duration of application means that it cannot damage a decoder. Some controllers will state error or similar on screen of the installation wiring is incorrect.

 

With the multimeter we are generally looking for continuity or lack of it. Assuming an 8-pin decoder socket we need to check each pin is connected to where we expect it to be, e.g. rail pickups, motor, lights, etc. There have been instances of locos leaving the factory with cross connections or solder tracking pin to pin on the socket. What we do not want is a connection between pins that should not be connected. These are basic checks to ensure all is well with the wiring, before plugging in the decoder. There is little you can check at this level on the decoder itself, but with it plugged into the loco and working you can with care check such things as power at the blue wire, response to function switch on the white, yellow, green and if it exists the purple wires.

 

I hope this gives you some idea of what to look for.

[Howbi]

@andy 321...........Before anything else it would be worth resetting the DCC27 Omni by writing 8 to CV8, assuming you have a controller capable of changing CVs, to see if that cures the lack of lights........HB