The black and white wire to the coils is the power wire into the coils. It should have 6 volts when the ignition key is turned on. The yellow or blue wire going to the points is the ground coil circuit and the plug fires when the points open breaking the circuit. Make sure when the points are closed they are making a good ground. You can check the points connectivity with a VOM.
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You MUST have at least two more wires/connectors coming from the main harness!
The black/white with double connector which comes from the kill switch connecting to the two black/white off the coils;
A yellow, coming from the contact breakers, which goes to the other side of one coil ;
A yellow/blue, also coming from the contact breakers, which goes to the other side of the second coil.
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Stock 78 harness has white/black wire to each coil. Yellow to one coil, yellow/blue to the other.
The yellow and the yellow/blue need to go to the correct pickup to match the plugs.
Doesn't matter which terminal you put the wires on at the coils though. As long as you have one w/b to each one. Y to one, Y/B to the other.
The dotted line wire shown is not in GL1100.Its only in GL1200.
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The Yellow and Black/White wires go to the Cylinder 1/3 coil, and the other black/white and blue wires go to the 2/4 coil, and polarity doesn't matter, so you can hook them into either screw hole.
Cylinders 1 and 2 are fired from a single coil and the 3 and 4 are fired from the other coil. See Diagram if you have a GL1100
