Headlight(Low beam) and Taillight inop

[Splittie]

First off, my bike is an '81 gs750L
OK, I got ready to head off to work today and when I turned my bike on, my high beam was on. I switched from high to low beam and I had no light, along with no taillight. Went back to high beam to check the taillight and still no taillight.
So,
1. No taillight with headlight in low or high beam
2. No headlight in low beam position.
3. Headlight ON in high beam position.
4. Tail lamp is good, changed out with new to be sure.
5. Taillight wiring looks good going under fender (Not tore up from hitting tire.)
6. Brake light comes on and off when brake applied.
7. Fuses looked fine.
8. WHERE DO I GO FROM HERE

I didn't have time to check any further as I would have been late to work.
I will start looking/checking wiring when I get home from work
Searched the forum, but no problems like this that I found.
Thanks for any help.

[doctorgonzo]

Well, as not fun as it sounds, probably continuity tests to check the wiring and that left hand control switch. If you don't have the wiring diagram, can probably find it on BassCliffs super, excellent, there's a special place for him motorcycle heaven site.

[Splittie]

Well, as not fun as it sounds, probably continuity tests to check the wiring and that left hand control switch. If you don't have the wiring diagram, can probably find it on BassCliffs super, excellent, there's a special place for him motorcycle heaven site.

Thanks for the quick response.
I have both a shop manual and a Clymers manual for the bike.
I kinda figured it would be something in the switch, so I will be checking that first thing this evening.

[doctorgonzo]

I don't know if the tail light power goes through that switch before it goes to the tailight or not.

If it makes you feel any better I spent the entire day yesterday broken down in a convenience store parking lot, running through the diagnostics to confirm my stator was bad after my almost new battery crapped out on the road. It was bad. $120 more dollars I would have rather spent on "fun" stuff like my new pipe or SS brake lines.

[Splittie]

Since I have started riding this bike, I have tried to make sure that I have a second mode of transportation to work JUST IN CASE.

[z1b900]

ground

i am 99.9999999% sure it is a ground wire, try grounding all your frame grounds to the minus on battery,,and check the left switch for ground off the handlebars,,

[Steve]

I don't know if the tail light power goes through that switch before it goes to the tailight or not.

Unless your 750 is substantially different than the 550, 650, 850 and 1100 I have worked on, the tail light power does not go through the switch on the left hand grip.

The only switch involved in the tail light circuit is the igniton key. The tail light has its own dedicated wire that can receive power when the key is in the RUN position or the PARK position. Basically, it should be on whenever the bike is running, even if you are able to control the headlight on your bike.

.

[BassCliff]

Contributors?

Well, as not fun as it sounds, probably continuity tests to check the wiring and that left hand control switch. If you don't have the wiring diagram, can probably find it on BassCliffs super, excellent, there's a special place for him motorcycle heaven site.

Mr. doctorgonzo,

Thank you for your kind words. Unfortunately I have no 750 information available on my site. I'd be happy to host some. What else could I do besides copy a manual from repairmanualclub.com? I'm open to suggestions.


Thank you for your indulgence,

BassCliff

[Splittie]

Problem Solved!!!

YEAH!!! \\/\\/
As soon as I got in from work, I tore into it and found that I had a ground wire, that the PO had so nicely hidden with tons of electrical tape, was broken.
I also found that my headlights bulb had simply blown out the low beam.
As for the taillight, the ground was the fix for it.
Well, tomorrow I will try to find a bulb to replace it and I should be good to go.
Thanks for the input guys.