Hi all just looking for some help I have a 1974 dt250a totally restored and was working fine last summer this year out of the blue I have no lights no horn  etc the only thing that’s working is the high beam indicator  the Speedo and rev counter backlights ? Any thoughts please . I assume that the lighting coil is ok as I have these bulbs are working?

Fuse blown, or maybe rectifier damaged?

If I got this right the low beam, high beam and back lights I believe work off lighting coil
So if they work but headlight L/H doesn't then perhaps the headlamp is bad? or maybe lighting coil isn't putting out enough?

Battery bad or missing? Most of the lights and horn work from battery with engine off.

Headlight, high beam indicator, and dash lights directly off stator with engine running (US models) as MSavitt said.

Bad battery can lead to blown headlight and other bulbs due to over-voltage... little bulbs usually blow too though.

More info needed.... what does "out of the blue" mean? Bike was sitting six months and you tried to ride it and lights didn't work? You were riding and lights failed? Or? Are you using original bulbs? Original electrical system? Have you installed voltage regulator upgrade per Service Bulletin?

Thanks for your comments mark t I was riding bike last summer all was fine then  no go so I changed rectifier installled all new bulbs it has a new fully charged battery so I’m a bit confused main fuse is still intact ? Could it be a bad earth ?

Battery usually earth to the frame close by, but if it plugs to the black & earths somewhere else check 'that black' for earthing. I think the main loom earths at the plug coil mount. Guessing a bit but instrument illuminating bulbs including high beam indicator run off the mag, so if they're not blowing then the regulator must be doing its job. & high beam likely just taps off the yellow to the headlight high. Hows the headlight bulb--sorry, had to ask. Does the brake light work--i guess not as is battery powered. Does your model have batt powered tail light. Ours is mag powered with headlight in NZ. Rectifier can't be connected back to front? can it. I'm lost--back in the corner. One more, fuse ok--been ask i know.

Thanks rt325 for your help it’s a new battery and in good condition I have no headlight no backlight no indicators no horn .I’m thinking maybe the headlight handlebar switch is faulty ? Maybe earth issues with that ?