Topic: Tail light issues.

[Ando13]

This has probably been discussed before but I couldn't find an answer to my problem on previous threads so here goes.
I have a 73 cb500 Four which I've been putting back together over the last couple of months. The bike was almost complete when I found it and I now have it running although very rough. The parts haven't been easy to find here in Oz but I've managed. The issue I have ATM is the tail light does not come on when I turn the head light on. All the other lights work fine including the brake light. I have no power at the rear or at the ignition on the Brown wire which is the feed to the tail light. Everything in the front light bowl seem ok. Could the problem be in the front light switch and does the wire go the there? I've checked the wire from front to back and there doesn't seem to be a breakage. All the wires coming from the ignition have power except the brown. The ignition is new.  Thanks.

[turkey4me]

I had a similar problem two weeks ago.  It was a broken wire on the back side of the key switch.  Good luck.

[DH]

Cal, does that model have a fuse block with a dedicated fuse for the tail light, or just the single main?

[Ando13]

I had a similar problem two weeks ago.  It was a broken wire on the back side of the key switch.  Good luck.

I just checked the back of the switch and although the feed to the tail light doesn't look to be broken there was no power getting through. The connection doesn't look very good so I will try to re solder it and check again. My switch is just a simple on/off with no Acc .

[Ando13]

The switch is from Wemoto. Its an after market switch that is supposed to work on most old Hondas. I linked the Tail light feed to the active Red and it lit up. So the problem is how to get power to the Brown tail light feed when the Head lights are switched ON. Any suggestions?

[Ando13]

The wiring is how the switch came new. I did re solder the B/W wire which is the one that should connect to the Brown.
The Black and Red wire have voltage when the ignition is on but the Green and B/W do not which is what I think the problem is.

[Ando13]

Well you'll all be happy to know the problem is sorted. The brown wire leading to the switch needed to be connnected to the brown and white wire coming from the light switch. The black and white wire as well as the green wire in the ingnition do nothing. Thanks to everyone for their advise and taking the time to comment.