Yamaha XN125 2000, Service Manual

Page: 249 / 259

ELEC
8-42
CARBURETOR HEATING SYSTEM
EAS00823
4. Thermo switch
• Disconnect the thermo switch from the wire
harness.
• Connect the pocket tester (
Ω
x 1) to the
thermo switch lead.
Positive tester probe
→
black
Negative tester probe
→
black
EAS00824
5. Carburetor heater
• Remove the carburetor heating element from
the carburetor.
• Connect the pocket tester (
Ω
x 1) to the
carburetor heating element.
Positive tester probe
→ → → → →
heating element
Negative tester probe
→
heating element
body
EAS00826
6. Wiring (of the entire carburetor heating system)
• Check the entire carburetor heating sys-
tem’s wiring
Refer to “CIRCUIT DIAGRAM”
• Is the carburetor heating system properly
connected and without defects?
YES NO
Replace the thermo
switch.
YES NO
Replace the carbu-
retor heating element.
YES
NO
This circuit is OK.
Properly connect or
repair the carburetor
heating system’s wir-
ing.
• Check the thermo switch for continuity at the
temperatures indicated below.
8¡C – 4¡C 19¡C – 3¡C
A COOL DOWN
B HEAT UP
• Does the thermo switch operated properly ?
• Measure the carburetor heater resistance.
Carburetor heating element
resistance:
6 ~ 12
Ω
at 20
°
C
• Is the carburetor heating element OK?