FWIW, mine does not light on DC, only when the propane is lit.  But you said "most," not "all."

---- David Beierl <dbeierl@ATTGLOBAL.NET> wrote: 
> At 08:31 PM 11/7/2015, Jim Felder wrote:
> >I guess so. But side from the color of the bulb, 
> >the rest of the discussion stands.Â
> 
> Except for the part about it not lighting on 
> DC.  It may not be intended to light on DC, but 
> most of them do because the ground reference 
> shifts when the DC goes on.  The signal driving 
> the LED is only a few millivolts (and it's the 
> only voltage in the van that's deliberately negative to chassis ground).
> 
> Yrs,
> d 

--
David McNeely