One defective ignition unit can sometimes cause the entire
ignition system to be inoperative. In this case, the trouble can be located
without test equipment.
A.
Disconnect
the three light green wires going from the ignition rectifier unit to the
ignition units.
B.
Connect
one wire at a time to its ignition, unit and check the spark for that cylinder.
If
two of the cylinders will spark when connected alone, the ignition unit for the
non-sparking cylinder is bad.
Make
sure the spark plug in the non-sparking cylinder is good.
Proceeding from that point, there are only four possible places for the trouble to be: the coil, the ignition unit, the ignition rectifier unit, or the signal generator.
By following the steps below it will be easy to pinpoint the defective part.
"BC" means bad cylinder. "GC" means good cylinder (either one of the remaining two).
I.
(a)
There are three light green wires coming from the ignition rectifier unit, and
one goes to each ignition unit. Take the two of these, which go to the BC
ignition unit and the GC ignition unit and reverse them.
(b) Check the spark for two
cylinders. If the trouble has shifted from the BC to the GC, the ignition
rectifier unit is bad. If the trouble remains in the BC, go to step two.
II.
(a)
Reverse the BC and GC plug wires so the BC wire goes to GC plug.
(b) There are three red wires, one from
each ignition unit to each coil.
Reverse the BC and GC red wires.
This can be done at either the junction near the coil or near the
ignition unit.
(c) Now check the spark for both
cylinders. If the trouble has switched
to the GC, the BG ignition coil is bad.
If the trouble is still in the BC, go on to the next step.
III.
(a)
Return the spark wires back to normal, but leave the red wires reversed.
(b) Each
ignition unit has a white wire coming from it.
Reverse the BC unit and the GC
unit white wires.
Once
the defective part has been located, return all wiring to normal.
CAUTION: Battery failure is not considered as a possible source of
ignition trouble since the motorcycle will start and run without the
battery. However, running without the
battery will eventually cause failure of the ignition units.