nighthawk 550 electrical problem

Krusty,

The wording is as follows: "Bad connection from the battery (+
through the ignition switch to the switched +12v supply-input on th
rectifier. Check the whole electrical circuit. This is one of the mos
difficult faults to find. Suspect the ignition switch itself, the fus
box and its connections. The rectifier thinks the battery voltage i
too low while the voltage is correct or too high. Disconnect al
terminals and clean them with contact cleaner." Hopefully this wil
clarify some things.

Jef

 

Yes, I think I understand what Electrex is trying to say. It's just
that running the battery *charging* wire from the rectifier DC output
through the ignition switch to the battery terminal is such a bad idea
because it requires the ignition switch to carry so much current.

However. There are some Hondas that have six terminals instead of five
terminals coming from the rectifier regulator.

The three AC inputs, a DC positive output and a DC negative output can
also be found on the typical five wire regulator. Charging voltage in a
five wire RR is monitored directly from the positive battery terminal
or from a point between one pair of diodes *inside* the regulator unit
itself in a five wire RR unit.

The sixth wire on some Hondas is a sensor wire. If I understand the
sensor wire business correctly from what some Honda riders have posted,
the sensor wire seems to monitor charging voltage at some remote point
on the battery bus or on the ignition bus. If the sensor circuit has to
add the voltage drop across dirty ignition switch contacts and corroded
electrical connectors, it may sense low charging voltage and may not
tell the silicon control rectifier inside the RR unit to ground out the
stator.

That could result in frying the stator.

It's no wonder Honda riders have been cutting off their electrical
connectors and soldering the wires together to get rid of all the high
resistance connections.

It seems to me that the best place to attach a sensing wire that's
supposed to monitor charging voltage would be directly to the battery!

So. How many wires total go to your rectifier regulator unit, five or
six?

And, have you done that open circuit voltage test I mentioned?

 

It seems that all Honda is doing by using a remote sensing wire is
saving about 1/100th of an amp current drain...

I learned a great deal about voltage regulation and electronic ignition
systems from a set of motorcycle repair manuals I found in the local
library back in the 1970's. The typical owner's manual will have wiring
diagrams showing all the wires going to mysterious empty boxes or
circles.

But this set of manuals showed diagrams and schematics and even gave
resistance values for components, so I copied those diagrams for future
reference as at least typical wiring and resistance values.

The current reducing resistors that tailor the current going to the
zener diode that triggers the thyristor in a shunt type voltage
regulator might total around 1100 ohms, as I recall.

If current flows through those resistors all the time, I calculate that
you'd have 0.01 amperes flowing through them, the battery would take
1400 hours, or 58 days to discharge down to 12 volts...