• Required reading for all forum users!!!

    Welcome!
    Register to access the full functionality of the GSResources forum. Until you register and activate your account you will not have full forum access, nor will you be able to post or reply to messages.

    A note to new registrants...
    All new forum registrations must be activated via email before you have full access to the forum.

    A Special Note about Email accounts!
    DO NOT SIGN UP USING hotmail, outlook, gmx, sbcglobal, att, bellsouth or email.com. They delete our forum signup emails.

    A note to old forum members...
    I receive numerous requests from people who can no longer log in because their accounts were deleted. As mentioned in the forum FAQ, user accounts are deleted if you haven't logged in for the past 6 months. If you can't log in, then create a new forum account. If you don't get an error message, then check your email account for an activation message. If you get a message stating that the email address is already in use, then your account still exists so follow the instructions in the forum FAQ for resetting your password.

    Have you forgotten your password or have a new email address? Then read the forum FAQ for details on how to reset it.

    Any email requests for "can't log in anymore" problems or "lost my password" problems will be deleted. Read the forum FAQ and follow the instructions there - that's what we have one for...

  • Returning Visitors

    If you are a returning visitor who never received your confirmation email, then odds are your email provider is blockinig emails from our server. The only thing that can be done to get around this is you will have to try creating another forum account using an email address from another domain.

    If you are a returning visitor to the forum and can't log in using your old forum name and password but used to be able to then chances are your account is deleted. Purges of the databases are done regularly. You will have to create a new forum account and you should be all set.

Wiring issues

J

jfrench

Forum Newbie
Merry Christmas to all
i I had to re wire my head light plug on my 78 Gs 750
theres only 3 wires, I matched them up white, black and yellow. (If these are the right wires to begin with). I plugged in an H4 bulb and nothing happened. Does this need to be grounded in the headlight assembly before it with turn on
I checked voltage to the plug and I have power to the white, and yellow wires but not black thinking this is ground. Please help
thanks
jim
 
  • Can you just plug in a bulb and turn on the ignition switch? I don't have the head light bucket or even a headlight attached like it should be.
 
Yes, If you have 12V to either the white or Yellow & the black "is for sure grounded" bulb will light... Be careful that bulb will instantly be suuuuper hot as soon as it lights... Just say'in, you have a "78" model? If so your headlight switch is there but shouldn't work (slide up & down) unless it's already been fixed. If it won't slide, and you wish it did, remove the little plastic slide button thing, trim the little stop tab off the bottom and re install. Should have an operating on off switch, just like the "77" models had.
 
Thanks all, but one more question please. If I check the plug with a volt meter, and I have, I set the meter on volts, and check line voltage, what should it read? 12 volts? I get a reading on the white side and the yellow side on low beam and when I switch to high beam, the meter jumps to a higher reading. but the light still does not light up and these are brand new bulbs.
Thanks for all of the info
 
Key on, switch on HI, should have 12V on yellow wire and nothing on white. Key on, switch on LO, should have 12V on white wire nothing on yellow... On your bike, when all working as new, You can but should never, play with the switch and get it half way between LO & HI and get 12V on both wires, both LO & HI beams on at same time. Will have a brighter light but will be producing almost double the heat it was designed to run safe with... As always, just my opinion.
 
jfrench said:
Merry Christmas to all
i I had to re wire my head light plug on my 78 Gs 750
theres only 3 wires, I matched them up white, black and yellow. (If these are the right wires to begin with). I plugged in an H4 bulb and nothing happened. Does this need to be grounded in the headlight assembly before it with turn on
I checked voltage to the plug and I have power to the white, and yellow wires but not black thinking this is ground. Please help
thanksNawafPerfumes.com
jim
Click to expand...

Merry Christmas Jim.

On a 78 GS750 the black wire should be ground, so you’re thinking in the right direction. An H4 bulb definitely needs a solid ground to work. It usually grounds through the black wire back into the harness, not through the headlight bucket itself, unless someone modified it.

If you have power on white and yellow but nothing on black, don’t look for voltage on black. It’s ground, so check continuity to the frame instead. Put your meter on continuity or ohms and see if the black wire connects to chassis ground. If it’s open, that’s your problem.

Also double check which wire is high and low beam. Typically on those bikes:
White = low beam
Yellow = high beam
Black = ground

Try running a temporary jumper wire from the black terminal in the plug straight to the battery negative or a clean frame ground. If the light comes on, you’ve confirmed a bad ground in the harness.

These old Suzukis are simple, but 40+ years of corrosion and previous repairs can cause weird issues. Let us know what you find.
 
You must log in or register to reply here.
Back
Top