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 coil wires 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.
Turn the ignition switch to OFF.
Remove the left upper inner fairing (see Upper Inner Fairing Removal in the Frame chapter).
Disconnect the alternator lead connector [A].
Connect the hand tester as shown in the table 1.

Special Tool - Hand Tester: 57001-1394
Start the engine.
Run it at the rpm given in the table 1.
Note the voltage readings (total 3 measurements).
Table 1 Alternator Output Voltage at 4 000 r/min (rpm)

If the output voltage shows the value in the table, the alternator operates properly. The regulator/rectifier is damaged.
If the output voltage shows a much lower reading than that given in the table, stop the engine and inspect the stator coil resistance.
Stop the engine.
Connect the hand tester as shown in the table 2.
Special Tool - Hand Tester: 57001-1394
Table 2 Stator Coil Resistance at 20°C (68°F)
If there is more resistance than shown in the table, or no hand tester reading (infinity) for any two leads, the stator has an open lead and must be replaced. Much less than this resistance means the stator is shorted, and must be replaced.
Any hand tester reading less than infinity (∞) indicates a short, necessitating stator replacement.
If the stator coil has normal resistance, but the voltage check showed the alternator to be defective; then the rotor magnets have probably weakened, and the rotor must be replaced.
Charging Voltage Inspection
Regulator/Rectifier InspectionOperational Cautions
1. Do not put two keys of any immobilizer system on the same key ring.
2. Do not submerge any key in water.
3. Do not expose any key to excessively high temperature.
4. Do not place any key close to magnet.
5. Do not place a heavy item on any key.
6. Do not grind any key or alter its ...
Interlock Operation Inspection
Raise the rear wheel off the ground with the stand [A].
1st Check
Start the engine to the following conditions
Condition:
Transmission Gear → 1st Position
Clutch Lever → Release
Sidestand → Down or Up
Turn the ignition switch to ON and push the starter butto ...
Stick Coil Inspection
Remove the stick coils (see Stick Coil Removal).
Measure the primary winding resistance [A] as follows.
Connect the hand tester between the coil terminals.
Set the tester to the × 1 Ω range, and read the tester.
Measure the secondary winding resistance [B] as follows.
Conn ...