Yamaha YZ450FA Automobile User Manual


 
7-45
ELECTRICAL COMPONENTS
ELECTRICAL COMPONENTS
CHECKING THE COOLANT TEMPERATURE
SENSOR
1. Remove:
• Coolant temperature sensor
Refer to "REMOVING THE CYLINDER
HEAD" section in the CHAPTER 4.
Handle the coolant temperature sensor
with special care.
Never subject the coolant temperature
sensor to strong shocks. If the coolant
temperature sensor is dropped, replace it.
2. Check:
• Coolant temperature sensor resistance
3. Connect:
• Tester
Tester (+) lead Brown lead "1"
Tester (-) lead Black/Blue lead "2"
4. Immerse the coolant temperature sensor in
a container filled with coolant.
Make sure the coolant temperature sensor ter-
minals do not get wet.
5. Place a thermometer "3" in the coolant.
6. Slowly heat the coolant, and then let it cool
to the specified temperature indicated in the
table.
Out of specification Replace.
CHECKING THE INTAKE AIR PRESSURE
SENSOR
1. Check:
• Intake air pressure sensor output voltage
2. Connect:
• Test harness S–pressure sensor (3P) "1"
• Tester
Tester (+) lead Pink/White lead (wire har-
ness color)
Tester (-) lead Black/Blue lead (wire har-
ness color)
3. Connect the FI diagnostic tool sub-wire har-
ness to a battery, and then set the switch on
the harness to "ON".
When checking the intake air pressure sen-
sor, do not start the engine.
4. Measure the intake air pressure sensor out-
put voltage.
Out of specification Replace.
B/L
Br
Coolant tempera-
ture sensor resis-
tance
Tester selector po-
sition
210 220 Ω (100
°C, 212 °F)
Ω×100
2.512.78 kΩ (20
°C, 68°F)
×1
Test harness S–pressure sensor
(3P):
YU-03207/90890-03207
Output voltage
Tester selector po-
sition
3.4 3.8 V DCV