Yamaha YP250R 2005, Service Manual

Page: 347 / 370

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– +
ELEC
AUTO CHOKE SYSTEM
YES
NO
4. Thermo switch (auto choke)
• Remove the thermo switch (auto choke)
from the radiator.
• Connect the pocket tester (
Ω ×
1) to the
thermo switch
1
as shown.
• Immerse the thermo switch in a container
filled with coolant
2
.
NOTE:
Make sure that the thermo switch terminals
do not get wet.
• Place a thermometer 3 in the coolant.
• Slowly heat the coolant, then let it cool
down to the specified temperature.
• Check the thermo switch for continuity at
the temperatures indicated in the table.
Test
step
Coolant temperature
Continu-
ity
Thermo switch
1
Less than 47 ± 3 °C
(116.6 ± 5.4 °F)
NO
2
More than 47 ± 3 °C
(116.6 ± 5.4 °F)
YES
3
More than 42 ± 3 °C
(107.6 ± 5.4 °F)
YES
4
Less than 42 ± 3 °C
(107.6 ± 5.4 °F)
NO
Steps 1 and 2: Heating phase
Steps 3 and 4: Cooling phase
WARNING
• Handle the thermo switch with special
care.
• Never subject the thermo switch to
strong shocks. If the thermo switch is
dropped, replace it.
T
R
.
.
Thermo switch (auto choke)
30 Nm (3.0 m · kg, 22 ft · lb)
È
The thermo switch circuit is open and the auto
choke is off.
É
The thermo switch circuit is closed and the
auto choke is on.
• Does the thermo switch operate properly
as described above?
Replace the thermo
switch (auto choke).