Running Light Only Works in "Park"

[Guest]

Hello,

I'm wiring up a new brake light on my 78 GS550E and having trouble getting the running light to work. The brake light works fine. Im using a dual filament light, and both filaments work fine.

I used my multimeter to check the brown (running light wire) from the plastic connection to the ignition, all the way back to the tail light connection. Everything checked out positive.

I had an extra ignition lying around so I threw it on out of curiosity and all of the sudden the running light works in the PARK setting. However, I'm still not getting light in the ON setting.


I have read through the other posts and know that in some cases the PARK and ON functions are controlled by separate fuses. However, I'm pretty darn sure my bike only has one fuse. It's just a simple in-line fuse on red wiring.

Any ideas?

Thanks!

[tom203]

By "running light", you really mean "tailight" - the light in same housing as brakelight that goes on with headlight.Do you still have an ON/OFF switch for headlight? does it work?

[murrayta]

Hi Tom,

Correct, I mean tail light. It's an aftermarket dual filament light. (brown wire)

I just noticed my tach and speedo backlights aren't working either. (grey wire)

The brown and grey wire should both get power when the ignition is in the ON position, however they are not.

I tried connecting a grey wire to the Orange power wire and BOTH and tach/speedo AND tail light come on. After removing that, I tried connecting the brown wire this time and again, BOTH lights came on.

So now I know that all the lights work properly, and somewhere the brown and grey wires must connect.

I'm stumped on why the brown and grey wires are not getting power on their own when the ignition is in the ON position.

Thanks for your help

[murrayta]

Also, this may be a silly question, but I need to clarify:

Is the tail light ONLY supposed to be on when the headlight is also switched on? I believe it is, but I just want to make sure.

If this is the case, I think I know the issue.

I replaced the original ON/OFF switch for the headlight the other day. The old switch had a grey wire that looked like it was triggered when the switch was in the ON position.

The simple new switch does not have a place for this. Therefore the grey wire (which also connects to brown) isn't getting power when the headlights are turned on.

Is my logic sound?

[chuck hahn]

It is on only with the headlight on if you have the switch that turns the headlight and instrument lamps off.

if your bike doesnt have the headlight switch then it should come on with the headlight when you turn the key on.

AND It should come on in the PARK position but the headlight is not on in the PARK position...just the taillight