2016 YAMAHA WR 450F sensor

THROTTLE BODY
8-9
Removing the injector
OrderPart name Q’tyRemarks
1 Fuel inlet pipe 1
2Injector 1
3 Gaskets 1
4 Throttle position sensor 1
5 Intake air pressure sensor 1
For installation, reverse the removal proce-
dure.
1
2
(2)
(2) 5
4 3
T.R.3.4 Nm (0.34 mlbf)
kgf, 2.5 ft
T.R.5 Nm (0.5 mlbf)
kgf, 3.6 ft
T.R.3.4 Nm (0.34 mlbf)
kgf, 2.5 ft

THROTTLE BODY
8-10
EAS2GC1352CHECKING THE INJECTOR
1. Check:• InjectorsObstruction  Replace, and check the fuel
pump and the fuel injection system.
Refer to “FUEL INJECTION SYSTEM” on
page 9-28.
Deposits  Replace.
Damage  Replace.
2. Check:
• Injector resistanceRefer to “CHECKING THE FUEL INJEC-
TOR” on page 9-81.
EAS2GC1353CHECKING THE THROTTLE BODY
1. Check:• Throttle bodyCracks/damage  Replace.
2. Check:
• Fuel passagesObstructions  Clean.
ECA
NOTICE
• Before removing the throttle body, clean
the area around the throttle body to pre-
vent dirt and other foreign material from
falling into the engine.
• If the throttle body is subject to strong shocks or dropped during cleaning, re-
place it.
• Do not use any caustic carburetor clean- ing solution.
• Do not directly push the throttle valves to open them.
• Do not loosen the throttle valve stopper screw “1”, throttle valve pulley nut “2”, or
throttle valve screw “3”. A loss of perfor-
mance may occur.
• Do not use compressed air to clean the throttle body. Foreign materials may ad-
here to the intake air pressure sensor pas-
sage “a” and fuel injector “b” in the
throttle body. 3. Check:
• Starter knob/idle screw passage “c”Obstruction  Blow out with compressed
air.
EAS2GC1354CHECKING THE THROTTLE BODY JOINT
1. Check: • Throttle body joint “1”Crack/damage  Replace.
1
2
3
ba
c
1

THROTTLE BODY
8-11
EAS2GC1355ADJUSTING THE THROTTLE POSITION
SENSOR
EWA
WARNING
• Handle the throttle position sensor with special care.
• Never subject the throttle position sensor
to strong shocks. If the throttle position
sensor is dropped, replace it.
1. Check: • Throttle position sensorRefer to “CHECKING THE THROTTLE PO-
SITION SENSOR” on page 9-79.
2. Adjust: • Throttle position sensor angle
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the Yamaha diagnostic tool. Refer to “YAMAHA DIAGNOSTIC TOOL” on
page 9-32.
b. Temporary tighten the throttle position sen- sor.
c. Check that the throttle grip is fully closed.
d. Connect the throttle position sensor to the wire harness.
e. Set the Yamaha diagnostic tool to “diagnos- tic mode”.
f. Choose the diagnostic code No. “01”.
g. Adjust the throttle position sensor mounted
angle until “11”–“14” appears on the Yama-
ha diagnostic tool.
h. After adjusting the throttle position sensor mounted angle, tighten the throttle position
sensor screws “1”.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1356INSTALLING THE INJECTOR
1. Install:• Fuel injector coupler “1”
TIP
Align the projection “a” on the fuel inlet pipe
with the slots “b” on the fuel injector coupler.
Yamaha diagnostic tool 90890-03231
Yamaha diagnostic tool (US) 90890-03234
Throttle position sensor screw 3.4 Nm (0.34 m·kgf, 2.5 ft·lbf)
T R..
1
1
a
b

ELECTRICAL COMPONENTS....................................................................... 9-60
CHECKING THE SWITCHES .................................................................. 9-64
CHECKING THE BULBS AND BULB SOCKETS .................................... 9-67
CHECKING THE FUSES ......................................................................... 9-68
CHECKING AND CHARGING THE BATTERY ........................................ 9-69
CHECKING THE RELAYS ....................................................................... 9-72
CHECKING THE DIODE .......................................................................... 9-73
CHECKING THE IGNITION SPARK GAP................................................ 9-73
CHECKING THE SPARK PLUG CAP ...................................................... 9-73
CHECKING THE IGNITION COIL ............................................................ 9-74
CHECKING THE CRANKSHAFT POSITION SENSOR........................... 9-74
CHECKING THE LEAN ANGLE SENSOR............................................... 9-75
CHECKING THE STARTER MOTOR OPERATION ................................ 9-75
CHECKING THE STATOR COIL ............................................................. 9-76
CHECKING THE RECTIFIER/REGULATOR ........................................... 9-76
CHECKING THE SPEED SENS OR ......................................................... 9-77
CHECKING THE FUEL SENDER ............................................................ 9-77
CHECKING THE RESISTER ................................................................... 9-77
CHECKING THE RADIATOR FAN MOTOR ............................................ 9-78
CHECKING THE COOLANT TEMPERATURE SENSOR........................ 9-78
CHECKING THE THROTTLE POSITION SENSOR ................................ 9-79
CHECKING THE THROTTLE POSITION SENSOR INPUT VOLTAGE .. 9-79
CHECKING THE INTAKE AIR PR ESSURE SENSOR ............................ 9-80
CHECKING THE INTAKE AIR TEMPERATURE SENSOR ..................... 9-80
CHECKING THE FUEL INJECTOR ......................................................... 9-81

IGNITION SYSTEM
9-3
1. Joint connector
2. Joint connector
4. AC magneto
9. Battery
10.Frame ground
11.Starter relay
12.Main fuse
22.ECU (engine control unit)
23.Ignition coil
24.Spark plug
30.Joint connector
35.Lean angle sensor
36.Engine stop switch
48.Frame ground
49.Ignition coil sub-lead
50.Negative battery lead

IGNITION SYSTEM
9-4
EAS2GC1360TROUBLESHOOTING
The ignition system fails to operate (no spark or intermittent spark).
TIP
Before troubleshooting, remove the following part (s):
1. Seat
2. Side cover (left/right)
3. Air scoop (left/right)
4. Fuel tank
5. Air filter case cover1. Check the fuse. Refer to “CHECKING THE FUSES”
on page 9-68. NG

Replace the fuse(s).
OK 
2. Check the battery. Refer to “CHECKING AND
CHARGING THE BATTERY” on
page 9-69. NG

• Clean the battery terminals.
• Recharge or replace the battery.
OK 
3. Check the spark plug. Refer to “CHECKING THE SPARK
PLUG” on page 3-40. NG

Re-gap or replace the spark plug.
OK 
4. Check the ignition spark gap. Refer to “CHECKING THE IGNI-
TION SPARK GAP” on page 9-73. OK

The ignition system is normal.
NG 
5. Check the ignition coil. Refer to “CHECKING THE IGNI-
TION COIL” on page 9-74. NG

Replace the ignition coil.
OK 
6. Check the crankshaft position sen- sor.
Refer to “CHECKING THE CRANK-
SHAFT POSITION SENSOR” on
page 9-74. NG

Replace the stator assembly.
OK 
7. Check the engine stop switch. Refer to “CHECKING THE
SWITCHES” on page 9-64. NG

Replace the engine stop switch.
OK 

IGNITION SYSTEM
9-5
8. Check the lean angle sensor.Refer to “CHECKING THE LEAN
ANGLE SENSOR” on page 9-75. NG

Replace the lean angle sensor.
OK 
9. Check the entire ignition system’s wiring.
Refer to “CIRCUIT DIAGRAM” on
page 9-2. NG

Properly connect or repair the ignition sys-
tem’s wiring.
OK 
Replace the ECU.

SIGNALING SYSTEM
9-21
1. Joint connector
2. Joint connector
3. Joint connector
7. Main relay
9. Battery
10.Frame ground
11.Starter relay
12.Main fuse
15.Indicator light
17.Fuel level warning light
18.Resistor
19.Fuel sender
22.ECU (engine control unit)
30.Joint connector
42.Joint connector
46.Speed sensor
47.Multi-function display
48.Frame ground
50.Negative battery lead