Checking The Thermo Switch - Yamaha XG250 Service Manual

Positive tester probe
●
Horn terminal "1"
Negative tester probe
●
Horn terminal "2"
Br
2
c. Measure the horn resistance.
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2. Check:
Horn sound
●
Faulty sound → Adjust or replace.
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a. Connect a battery (12 V) to the horn.
b. Turn the adjusting screw "1" until the speci-
fied horn sound is obtained.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS28270

CHECKING THE THERMO SWITCH

1. Remove:
Thermo switch
●
(from the thermostat housing)
EWA13830
WARNING
Handle the thermo switch with special
●
care.
Never subject the thermo switch to strong
●
shocks. If the thermo switch is dropped,
replace it.
P
1
1
ELECTRICAL COMPONENTS
2. Check:
Thermo switch continuity
●
Out of specification → Replace the thermo
switch.
Test step Coolant temperature
Less than 16±3°C
1
(60.8±5.4°F)
More than 16±3°C
2
(60.8±5.4°F)
More than 11±3°C
3
(51.8±5.4°F)
Less than 11±3°C
4
(51.8±5.4°F)
Step 1 and 2: Heating phase
Step 3 and 4: Cooling phase
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a. Connect the pocket tester (Ω × 1) to the ther-
mo switch "1" coupler as shown.
b. Immerse the thermo switch in a container
filled with coolant "2".
c. Place a thermometer "3" in the coolant.
3
d. Slowly heat the coolant, then let it cool down
to the specified temperature.
A. Heating phase
B. Cooling phase
e. Check the thermo switch for continuity.
7-46
Continuit
y
YES
NO
NO
YES
B
B
1
2