Yamaha 2003 YFZ450S, Service Manual

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– +
ELEC
SIGNAL SYSTEM
YES
NO
YES
NO
YES NO
3. Voltage
• Connect the pocket tester (DC 20 V) to the
indicator light connector (wire harness
side) as shown.
Positive tester probe
→
red/black
1
Negative tester probe
→
white/blue
2
• Set the main switch to “ON”.
• Measure the voltage (12 V) of red/black
1
and brown
2
at the indicator light coupler.
• Is the voltage within specification?
The wiring circuit
from the main switch
to the indicator light
connector is faulty,
repair it.
4. Diode
• Remove the diode from the coupler.
• Connect the pocket tester (
Ω ×
1) to the
diode terminals as shown.
• Check the diode for continuity as follows.
Positive tester probe
→
blue/black
1
Negative tester probe
→
white/blue
2
Continuity
Positive tester probe
→
white/blue
2
Negative tester probe
→
blue/black
1
No
continuity
NOTE:
When you switch the tester’s positive and
negative probes, the readings in the above
chart will be reversed.
• Is the diode OK?
Replace the diode.
5. Start switch
• Check the start switch for continuity.
Refer to “CHECKING THE SWITCHES”.
• Is the start switch OK?
The circuit is not
faulty. Replace the handle-
bar switch.
L / B
W / L
1
2