Yamaha XS650SE, Shop Manual

Page: 93 / 215

B. CHARGING SYSTEM
1. Block Diagram
rectifier)
2.
a.
1)
3)
A.C. Generator/Voltage Regulator
Output voltage check
Remove the seat and left side cover.
Connect a D.C. voltmeter to the battery
terminals and start the engine.
Accelerate the engine to approximately
2,000 r/min or more and check the gener-
ated voltage.
, Generated voltage: 14.2
_ _ _ _ _ _ _
14.5
14.2 - - - -
r - - - - -
V I
8
Engine revolutions
NOTE:
Remove the headlight fuse (l0A) in the fuse
box so that the headlight does not turn on
when the engine is started. Do not turn on
the signals.
4) If the indicated voltage cannot reach
the specification, then perform the fol-
lowing tests.
- C A U T I O N :
Never disconnect the wires from the battery
while the generator is in operation. If the
battery is disconnected, the voltage across
the generator terminals will increase, damag
ing the semiconductors.
b. Brush
Check the brush length. Replace brush
if at, or near, limits. Check the brush
spring pressure by comparing it with a
new spring. Replace the old spring if it
is weak.
Minimum brush length: 7 mm (0.28 in)
c. Rotor coil/Stator coil
Check the resistance between terminals
using the Yamaha Pocket Tester or other
circuit tester as shown. If resistance is
out of specification, check the coil
connections. If the coil connections are
good, then the coil is broken inside and
it should be replaced.
Rotor coil resistance (Green-Brown):
10% at (68°F)
coil resistance (White-White):
10% at 20°C (68°F)