running light

[Btaylor1214]

OK so a few might have seen a posting on here for two katanas 91 and 89. Started at 1500 but fropped to 500. I took the road trip and bought them . (that makes 4 katanas in my garage. )
On the one that runs, the tail light only comes on when you brake. The running light doesnt come on. I was just wondering if there could be some minor issue (already replaced the bulb).
I just wanna make sure its not something stupid before i start ripping all the plastics off and tracing the wires. ( ripping the plastics is gonna be a pain, lots of zip ties and rigging. )
Any help would be appreciated

[Patch's]

Not sure if I missed it but what model is it?
I just happen to print off the diagram for the 89-94 1100F so looking at it the white &bl. stripe is your power for the brakes now you obviously have a ground or it wouldn't light so looks like you may want to check with a light probe to ground if you have power with the ing. switch in the on position to the wire I show here which is black with red tracer which leaves the back & white as your common/ground for the tail light and flashers, if your flasher work again that only leaves the black and red as the problem you should find a connection under your ing. switch it's a tail about 10" down and to your right as well,
if you disconnect it then you can read ohms between the tail plug and that one that will tell you if there is a brake along the path if so then splice in a new 18/16 gauge wire from plug to plug and tie rap or tape it to the old harness!
Hope that helps