88 K100 Tail Light & Parking Lamp wont work

Tail Light & Parking Lamp (Mini Head light) wont work.

I know that the fuse is good and I replaced the Tail Light Bulb Monitor twice and it didn't help. I know that there is no power at the harness plug going to the tail section for the tail light.

The Tail Light Bulb Monitor is supposed to keep the instrument warning light lit if a tail light does not function. It goes off after applying the brakes just like it normally would.

The Tail Light Bulb Monitor socket connection 58A goes to the tail light bulb When I apply 12v+ here the tail light goes on. Socket connection 31 is ground and I verified that I am getting a good ground and the Bulb Monitor.


I removed and cleaned the multiple ground wire connection under the tank.

Just want to be clear here this is NOT a dead or corrosive bulb, socket, or dirty plug.

Every other light and turn signal works well.

Any suggestions....

Thanks.

K100 Parking lamp

The common point is the Ign switch.
When the ign switch is in the "P" position the front parking lamp and the tail light should be on. The bulb monitor is for the tail light and brake light during normal operation. (not in park). Is the tail light working normally when the engine is running?
Good Luck!
The Lonerider

Thank you Lonerider

The tail light will NOT come on when I put the ignition switch in park or when the engine is running.

Thanks for pointing out the common point I'll have to take a better look at the ignition switch.

Problem Solved thanks again Lonerider...

I traced the Ignition switch "Park" wire 58A to the #2 fuse in the wiring diagram. I swapped out the fuse and the tail light flickered. The wire leading to the fuse inside the relay box was not connected well.

I simply took a pair of needle nose pliers and shoved it toward the fuse while holding the fuse with the other hand.

Now the light works perfectly.

Thanks again Lonerider for steering me in the right direction.

K100 Parking lamp

Glad to be of help!
Ride Safe
The Lonerider