Checking The Air Pressure Sensor; Checking The Engine Temperature Sensor - Yamaha F150A Service Manual

Air temperature sensor resistance
(reference data):
2.2–2.7 kΩ at 20 °C (68 °F)
0.32 kΩ at 80 °C (176 °F)
9. Install the air temperature sensor, and
then connect the air temperature sensor
coupler.

Checking the air pressure sensor

1. Disconnect the air pressure sensor cou-
pler "a".
2. Turn the engine start switch to ON, and
then measure the input voltage at the air
pressure sensor coupler.
a
Air pressure sensor input voltage:
Orange (O)–Black (B)
4.75–5.25 V
3. Turn the engine start switch to OFF.
4. Remove the air pressure sensor.
5. Connect the special service tools "1" and
"2".
6. Apply negative pressure to the air pres-
sure sensor slowly, and then measure
the output voltage.
2
Vacuum/pressure pump gauge set "1":
Test harness (3 pins) "2": 90890-06869
Air pressure sensor output voltage:
B O
7. Turn the engine start switch to OFF.
8. Disconnect the special service tools.
9. Install the air pressure sensor. See
10. Connect the air pressure sensor coupler.
Checking the engine temperature
sensor
1. Disconnect the engine temperature sen-
2. Turn the engine start switch to ON, and
5-24
Ignition unit and component
P/G
B
O
B
G/W G
2
90890-06945
Pink/Green (P/G)–Black (B)
3.21 V at –20.0 kPa
2
(–0.20 kgf/cm , –2.9 psi)
2.16 V at –46.7 kPa
(–0.467 kgf/cm 2 , –6.8 psi)
"Intake manifold and vapor separator" (6-
34).
sor coupler "a".
then measure the input voltage at the
engine temperature sensor coupler.
1
0
1
2
3
4
5
6
7
8
9
10
A