Charging Voltage Inspection
Check the battery condition.
Warm up the engine to obtain actual alternator operating
Remove the seat (see Frame chapter).
Check that the ignition switch is turned off, and connect
the hand tester to the battery as shown in the table.
Regulator/Rectifier Output Voltage
Tester (+) to
25 V DC
Turn on the ignition switch and start the engine, and note
the voltage readings at various engine speeds with the
headlight turned on and then turned off (To turn off the
headlight, disconnect the headlight connector in the head-
light unit). The readings should show nearly battery volt-
age when the engine speed is low, and as the engine
speed rises, the readings should also rise. But they must
be kept under the specified voltage.
Turn off the ignition switch to stop the engine, and discon-
nect the hand tester.
If the charging voltage is kept between the values given in
the table, the charging system is considered to be working
If the output voltage is much higher than the values spec-
ified in the table, the regulator/rectifier is defective or the
regulator/rectifier leads are loose or open.
If the battery voltage does not rise as the engine speed
increases, then the regulator/rectifier is defective or the
alternator output is insufficient for the loads. Check the
alternator and regulator/rectifier to determine which part
There are three types of alternator failures: short, open
(wire burned out), or loss in rotor magnetism. A short or
open in one of the stator coil leads will result in either a
low output, or no output at all. A loss in rotor magnetism,
which may be caused by dropping or hitting the alternator,
by leaving it near an electromagnetic field, or just by aging,
will result in low output.
To check the alternator output voltage, do the following
Remove the alternator outer cover and disconnect the al-
ternator connector [A].
Connect the hand tester to the alternator connector as
Special Tool - Hand Tester: 57001-1394
Start the engine.
Run it at 3 000 rpm of the engine speed.
Note the voltage readings.
Tester (−) to
ELECTRICAL SYSTEM 16-35
@3 000 rpm