blowing fuses

i have a 1979 kz750 twin started blowing main fuses if i unhook the headlight fuse its ok no lights tho when i put the fuse back the main fuse gets hot. i have a sevice manule i have ben studing the wire diagram havent found anything yet. one thing i did find is the brake light failure indicator light bulb was bad when replaced the bulb blinks not shure what this means. if anyone can help would be appreciated

You're gonna have to open up the headlight housing looking for wires with damaged insulation that have rubed together or are touching a Black with Yellow stripe wire which is usually the ground circuit on most Kawasaki bikes.

Color Codes On Most Kawasaki’s (written for 1980’s bikes)

HEADLIGHT
RED with BLACK stripe, High Beam.
RED with YELLOW stripe, Low Beam.
BLACK with YELLOW stripe, the ground circuit.

BRAKE/TAIL LIGHT Can be an # 1157 dual filament bulb
RED, Running or Tail Light.
BLUE,(sometimes with a Red stripe) Brake Light Circuit.
BLACK with YELLOW stripe, the ground circuit.

LEFT FRONT TURN SIGNAL Can be an #1157 dual filament bulb
GREEN, Left front turn signal circuit.
BLUE, Left front running light circuit.
BLACK with YELLOW stripe, the ground circuit.

RIGHT FRONT TURN SIGNAL Can be an # 1157 dual filament bulb
GREY, Right front turn signal circuit.
BLUE, Right front running light circuit.
BLACK with YELLOW stripe, the ground circuit.

LEFT REAR TURN SIGNAL Can be an #1156 single filament bulb
GREEN, Left rear turn signal circuit.
BLACK with YELLOW stripe, the ground circuit.

RIGHT REAR TURN SIGNAL Can be an #1156 single filament bulb
GREY, Right rear turn signal circuit.
BLACK with YELLOW stripe, the ground circuit.


The Dreaded Shorting/Intermittent Electrical Problem!


Here is the most basic method I know(Taken from www.kzrider.com by member Patton)

1. Charge your battery and have it load tested if you can. The floating ball hydrometer can be used to check the specific gravity of the charged cells in the battery.

2. Disconnect the Black lead from the (-) Battery terminal... or Red from the (+) Battery terminal, it does not matter which one. Just 1, not both!

3. Connect one of the following test setups in series with the Battery terminal and lead:
3.1 A 12 V light bulb,
3.2 A 12 V test light,
3.3 A 12 V test buzzer or,
3.4 A 12 V horn... you get the idea.

4. With the Ignition Switch OFF, go through your harness and wiggle the wires while looking/listening for the test setup to go on/start buzzing.

5.With the Ignition Switch ON, repeat the test except this time the looking/listening for the test setup to go off/stop buzzing.

6. Be prepared to open the Ignition switch and check/test for solder joint failure and or circuit board micro breaks (don't ask how I know this ).

7. Be prepared to pull the wires out of the Head Light to test for failures at or near the grommet.

8. Be prepared to open the harness at or near the Steering Neck for failures. This is where wires tend to exhibit fatigue due to repetitive movement.

9. Be prepared to open the left and right switch gear to search for rust and or broken parts. CAUTION: watch out for flying springs, ball bearings and stuff. Do indoors on White sheet (again don't ask).

10. Be prepared to follow the heavy gauge wire from the Starter Solenoid (Relay) to the starter for bare wire exposure. Especially near bends and grommets.

11. If you can reproduce the fault symptom your are pretty much home free. Be prepare to find and repair/replace any internal wire breaks, insulation break downs, exposed wires, rubber grommet failures, etc. Often, shrink tubing will solve the problem temporarily until something better can be done.

12. I use a very good electrical contact cleaner/preservative called De-oxit made by Caig Labs in San Diego Ca. Their website is www.deoxit.com It can be purchased at Radio Shack and any other electronic supply store. I use it on all of my motorcycle’s electrical connectors , in my home entertainment center’s stereo patch cords and cordless phones charging cradles.