total lighting failure

[Watfordwhite]

Just finished the rebuild on the S2, everything worked as it should, booked it into an MOT, and low and behold total lighting failure. No lights and no horn.
Ignition works fine, the bike runs and starts as she should. All bulbs work and checked. power to the Junction Box from the stator, power going in and coming out of the MB regulator, even power in the headset JB. Still no lights? Earth from frame to engine OK, earth on headset OK.
Totally stumped!!!!!
The only change has been adding a fuel warning light and USB charger in the tool box. This runs from the DC side of the MB regulator. No power here also. But power in the JB.
So no AC lighting / horn, no DC power.
HELP???

[coaster]

Do you have an ignition switch fitted?

[Watfordwhite]

Yes but it is only running the kill switch

[Watfordwhite]

Engine runs and starts 1st time

[coaster]

The lights and ignition are completely separate circuits. You say you have power at the headset JCN box but what about the feed into the light switch? All connections should be pulled, checked and re-connected. Also check your earth connections are sound.

[St George]

Hi, There is a thread just put on here' How to test lights with a battery charger.' This may help you. Your headset probably looks like mine when you saw it back in January. I think a spare battery would be better than a charger. Regards Colin.

[Watfordwhite]

Turns out after lots of head scatching. The S3 junction box went open circuit. Giving both AC and DC to all circuits. Blown the MB reg, the usb charger and the low fuel warning led. Now fixed. Now the MB shorty reed valve rubber carb mount has a slit in it. This girl is fighting me all the way.... MB have no stock of new rubber mounts. Just my luck.
It's been a bad day.

[MickYork]

Turns out after lots of head scatching. The S3 junction box went open circuit. Giving both AC and DC to all circuits. Blown the MB reg, the usb charger and the low fuel warning led. Now fixed. Now the MB shorty reed valve rubber carb mount has a slit in it. This girl is fighting me all the way.... MB have no stock of new rubber mounts. Just my luck.
It's been a bad day.

I can confirm you have a Lambretta

[Watfordwhite]

You could of told me Mick before I started this madness...