Checking The Intake Air Temperature Sensor; Checking The Fuel Injector - Yamaha SR400 2014 Service Manual

• Positive tester probe
pink/white (wire harness color)
• Negative tester probe
black/blue (wire harness color)
2 1 1
B/L
c. Turn the main switch to "ON".
d. Measure the intake air pressure sensor out-
put voltage.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS28421
CHECKING THE INTAKE AIR
TEMPERATURE SENSOR
1. Remove:
• Intake air temperature sensor
(from the air filter case.)
Refer to "GENERAL CHASSIS" on page 4-1.
EWA14110
WARNING
• Handle the intake air temperature sensor
with special care.
• Never subject the intake air temperature
sensor to strong shocks. If the intake air
temperature sensor is dropped, replace it.
2. Check:
• Intake air temperature sensor resistance
Out of specification  Replace.
Intake air temperature sensor re-
sistance
290–390 @80 C (290–390
@176 F)
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester (  100) to the in-
take air temperature sensor terminal as
shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
b. Immerse the intake air temperature sensor
1 3
P L
L
P/W
B/L
ELECTRICAL COMPONENTS
"1" in a container filled with water "2".
TIP
Make sure that the intake air temperature sensor
terminals do not get wet.
c. Place a thermometer "3" in the water.
d. Slowly heat the water, then let it cool down to
the specified temperature.
e. Measure the intake air temperature sensor
resistance.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3. Install:
• Intake air temperature sensor
Refer to "GENERAL CHASSIS" on page 4-1.
Intake air temperature sensor
screw
2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
EAS2RD1042

CHECKING THE FUEL INJECTOR

1. Remove:
• Fuel injector
Refer to "THROTTLE BODY" on page 6-9.
2. Check:
• Fuel injector resistance
Out of specification  Replace the fuel injec-
tor.
Resistance
12.0 
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Disconnect the fuel injector coupler from the
fuel injector.
b. Connect the pocket tester (  10) to the fuel
injector coupler as shown.
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
7-72