Hornby super detailed 31 light question!

[Andy7]

So I have converted a Hornby super detailed 31111 to 31105 in Network Rail colours. As part of this I have fitted a centre headlight each end using Bachmann cab lights that I had spare. These are working spot on as are the rear red lights, (this is on DCC, would work fine on DC though). Now the problem is I can't seen to get the front marker lights to work. I assume they should work fine from the factory but I never tested prior to conversion! No wiring is loose and I simply soldered the headlight wires to the marker light wiring in parallel. Would this be the problem and should the lights be in series?

 

Any help or suggestions would be much appreciated before I start taking it apart again.

 

Thanks in advance.

[tractor_37260]

So I have converted a Hornby super detailed 31111 to 31105 in Network Rail colours. As part of this I have fitted a centre headlight each end using Bachmann cab lights that I had spare. These are working spot on as are the rear red lights, (this is on DCC, would work fine on DC though). Now the problem is I can't seen to get the front marker lights to work. I assume they should work fine from the factory but I never tested prior to conversion! No wiring is loose and I simply soldered the headlight wires to the marker light wiring in parallel. Would this be the problem and should the lights be in series?

 

Any help or suggestions would be much appreciated before I start taking it apart again.

 

Thanks in advance.

Hi Andy

             You may find, that when adding the headlight led to the same circuit as the markers, it's not leaving enough voltage in the circuit to light the markers, due to the built in factory circuit resistance. I had this problem in the past when fitting additional lights to locos. If you disconnect one of the headlight wires, do the markers then work OK ?  If so the new headlights will need to be wired from a split function output feed with their own resistor, commons being joined.

There is one other possible cause, some Hornby DCC locos are wired negative common, whereas positive common is the norm for DCC.  You need to ensure your connecting pos+ to pos+ and - to -  etc when adding the new headlight leds to the existing marker lights.

 

HTH

Ken