Snowmobile Yamaha FX10X, FX10RTX, FX10RTRX, FX10RTRAX, FX10MTX, FX10MTRX, FX10MTRAX. Manual - part 74

7-26

FI

FUEL INJECTION SYSTEM

OIL PRESSURE SWITCH

1. Disconnect:

• Oil pressure switch coupler 1 

2. Connect:

• Pocket tester

(between the engine ground and oil pressure
switch terminal)

1

3. Check:

• Oil pressure switch continuity

No continuity 

→ Replace the oil pressure

switch.

INTAKE AIR TEMPERATURE SENSOR

1. Remove the intake air temperature sensor.

CAUTION:

Handle the intake air temperature sensor with
special care. Never subject it to shock or allow
it to be dropped. If it is dropped, it must be
replaced.

2. Connect:

• Pocket tester

(to the intake air temperature sensor)

NOTE:

Set the tester selector to the “

Ω × 100” position.

3. Immerse the intake air temperature sensor 1 in

water 2 and check the intake temperature sen-
sor operation.

3 Thermometer

4. If the intake air temperature sensor operation is

defective, replace it.

5. Install the intake air temperature sensor.

Intake air temperature sensor resis-
tance:

290 ~ 390 

Ω at 80 °C (176 °F)

3

1

2

7-27

FI

FUEL INJECTION SYSTEM

ISC (IDLE SPEED CONTROL) UNIT

NOTE:

Do not remove the ISC (idle speed control) unit
completely from the throttle body.

1. Inspect:

• ISC (idle speed control) unit

Inspection steps:

• Disconnect the ISC (idle speed control) unit

coupler from the ISC (idle speed control) unit.

• Connect the pocket tester (

Ω × 10) to the termi-

nals of the ISC (idle speed control) unit.

• Measure the ISC (idle speed control) unit resis-

tance.
Out of specification 

→ Replace the throttle

body.

Positive tester probe 

→ Red/Green 1 

Negative tester probe 

→ White/Green 2 

Positive tester probe 

→ Brown/Blue 3 

Negative tester probe 

→ Pink/Blue 4 

Pocket tester:

90890-03112

Analog pocket tester:

YU-03112-C

ISC (idle speed control) unit resis-
tance:

57 ~ 63 

Ω at 20 °C (68 °F)

R/G

P/L

R/Y

Br/L

W/G

R/Y

2

1

3

4

7-28

FI

AIR FILTER CASE

AIR FILTER CASE

Order

Job name/Part name

Q’ty

Remarks

Air filter case removal

Remove the parts in the order listed below.

Steering column

Refer to “STEERING” in CHAPTER 3.

Radiator cover

Refer to “RADIATOR” in CHAPTER 6.

1

Intake air temperature sensor coupler

1

Disconnect.

2

Intake air temperature sensor

1

3

Air filter case cover

1

4

Air filter element frame

1

5

Air filter element

1

6

Radiator bolt

4

7

Air filter case joint clamp screw

3

Loosen.

8

Oil tank breather hose

1

Disconnect.

9

Cylinder head breather hose

1

Disconnect.

10

Air vent hose

1

Disconnect.

11

Air filter case

1

For installation, reverse the removal proce-
dure.

New

New

2

1

7

É

11

3

4

5

9

8

10

É

È

È

É

7

7

6

6

3 Nm (0.3 m 

•

 kg, 2.2 ft 

•

 lb)

È:   

7 Nm (0.7 m 

•

 kg, 5.1 ft 

•

 lb)

É:   

7-29

FI

THROTTLE BODY

THROTTLE BODY

Order

Job name/Part name

Q’ty

Remarks

Throttle body removal

Remove the parts in the order listed below.

Coolant

Drain.
Refer to “COOLING SYSTEM” in CHAPTER 
2.

Steering column

Refer to “STEERING” in CHAPTER 3.

Radiator

Refer to “RADIATOR” in CHAPTER 6.

Air filter case assembly

Refer to “AIR FILTER CASE”.

1

Fuel injection system sub-wire harness 
coupler

1

Disconnect.

2

Fuel hose

1

Disconnect.

3

Air vent hose

1

4

Throttle cable

1

5

Throttle body heater inlet hose

1

6

Throttle body heater outlet hose

1

7

Throttle body joint clamp screw

6

Loosen.

8

Throttle body assembly

1

9

Throttle body joint

3

For installation, reverse the removal proce-
dure.

1

2

4

5

6

3

8

9

9

9

È

È

È

È

È

È

3 Nm (0.3 m 

•

 kg, 2.2 ft 

•

 lb)

È:   

7

7

7

7

7

7