I bought an 87 K75 a week ago. Sorting many things out. My rear bulb sensor is on all the time. I've checked the rear bulb. Working fine in running light mode and also works correctly with either the front brake lever or rear foot brake pedal.

Any suggestions on what I can check next?

Also, this bike has been changed to a manual cooling fan switch. When I turn it on, the battery/charge light comes on and stays on until I switch the fan off.

Suggestions?

Brian in Austin, TX

the bulb warning indicator  stays lit from ignition on .....until both the front and rear brakes are pressed- activated .....for that session

need pics brian .....right next to the charge indicator is the temp - overheat indicator ....if the switch is wired for manual control  there is a technique (common solution ) that turns the warning lamp on as well, during fan activation .

charlie99 wrote:the bulb warning indicator  stays lit from ignition on .....until both the front and rear brakes are pressed- activated .....for that session

need pics brian .....right next to the charge indicator is the temp - overheat indicator ....if the switch is wired for manual control  there is a technique (common solution ) that turns the warning lamp on as well, during fan activation .

Hey Charlie, yes I read up on the bulb warning light before posting. Mine stays on constantly no matter how many times I used the front and rear brake levers, either together or separately.

The other light coming on is the charge light, not the temp light which is under the charge light. It comes on when I turn on the cooling fan and stays on until I turn the fan off.

re charge light .....at what engine revs does this happen ....don't forget that most alternators do no charging till they get to about 1500 and above revs ......if its at idle that would seem to be about correct to me.

the bmu (bulb monitor unit )  (under the tank ) could have some issues (broken solder connections etc ?)....make a note of it  and when you go under there for more fixes    that might be a good time to explore ?

 regards

The tail light/stop light warning bulb can sometimes be activated if the tail and/or the brake lights are nearing the end of their lives. Replace both bulbs and see how you go.

DeoxIT...the red stuff (D5). Use it. On every bulb/switch/connection on your bike. Be amazed. Tell your friends. Post a reply and thank me.

Also, if the brake lamp should be defective.... the tail bulb will glow brighter when pressing the brakes, sometimes fooling the operator into believing that both are operable when they are not.
  Remove the bulb sockets from the tail housing to double check the operation of the brake lamp bulb.
Regards, Ibj...