2016 YAMAHA WR 450F sensor

FUEL INJECTION SYSTEM
9-44
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
3 Wire harness continuity. Open or short circuit
 Re-
place the wire harness.
Between intake air tempera-
ture sensor coupler and ECU
coupler.
black/blue–black/blue
brown/white–brown/white Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 4.
4 Installed condition of intake air temperature sensor.
Check for looseness or
pinching. Improperly installed sensor

Reinstall or replace the
sensor. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 5.
5 Defective intake air tempera- ture sensor. Execute the diagnostic mode.
(Code No. 05)
When engine is cold:
Displayed temperature is
close to the ambient temper-
ature.
The displayed temperature is
not close to the ambient tem-
perature.
 Check the intake
air temperature sensor.
Replace if defective.
Refer to “CHECKING THE
INTAKE AIR TEMPERA-
TURE SENSOR” on page 9-
80. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 6.
6 Malfunction in ECU. Replace the ECU.
Fault code No. 30
Item Latch up detected.
Fail-safe system Unable to start engine
Unable to drive vehicle
Diagnostic code No. 08
Diagnostic tool display Lean angle sensor output voltage
• 0.4–1.4 (upright)
• 3.7–4.4 (overturned)
Procedure Remove the lean angle sensor and incline it more than 45 degrees.
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 The vehicle has overturned. Raise the vehicle upright. Push the start switch. Fault code number is not dis-
played  Service is finished.
Fault code number is dis-
played  Go to item 2.
Fault code No.
22
Item Intake air temperature sensor: open or short circuit detected.

FUEL INJECTION SYSTEM
9-45
2 Installed condition of lean an-gle sensor. Check the installed direction
and condition of the sensor. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 3.
3 Defective lean angle sensor. Execute the diagnostic mode. (Code No. 08)
Replace if defective.
Refer to “CHECKING THE
LEAN ANGLE SENSOR” on
page 9-75.Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 4.
4 Malfunction in ECU. Replace the ECU.
Fault code No. 33
Item Ignition coil: open or short circuit detected in the primary lead
of the ignition coil.
Fail-safe system Unable to start engine
Unable to drive vehicle
Diagnostic code No. 30
Actuation Actuates the ignition coil five times at one-second intervals.
The engine trouble warning light and the “WARNING” on the
Yamaha diagnostic tool screen come on each time the ignition coil
is actuated.
Procedure Check that a spark is generated five times.
• Connect an ignition checker.
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of ignition coil coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 3.
Fault code No.
30
Item Latch up detected.

FUEL INJECTION SYSTEM
9-46
3 Connection of sub wire har-ness coupler.Check the lock-
ing condition of the
coupler.Disconnect the cou-
pler and check the pins (bent
or broken terminals and lock-
ing condition of the pins). Improperly connected

Connect the coupler secure-
lyor repair/replace the sub
wire harness. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 4.
4 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
Between ignition coil coupler
and ECU coupler.
orange–orange Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 5.
5 Installed condition of ignition coil.
Check for looseness or
pinching. Improperly installed sensor

Reinstall or replace the
sensor. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 6.
6 Defective ignition coil. (test the primary coils for continu-
ity) Check the ignition coil.
Replace if defective.
Refer to “CHECKING THE
IGNITION COIL” on page 9-
74. Start the engine and let it idle
for approximately 5 seconds.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 7.
7 Malfunction in ECU. Execute the diagnostic mode (diagnostic code No. 30).
No spark  Replace the
ECU.
Fault code No. 33
Item
Ignition coil: open or short circuit detected in the primary lead
of the ignition coil.

FUEL INJECTION SYSTEM
9-48
TIP
Before troubleshooting, disconnect the starter motor lead from the starter relay.
Fault code No. 41
Item Lean angle sensor: open or short circuit detected.
Fail-safe system Unable to start engine
Able to drive vehicle
Diagnostic code No. 08
Diagnostic tool display Lean angle sensor output voltage
• 0.4–1.4 (upright)
• 3.7–4.4 (overturned)
Procedure Remove the lean angle sensor and incline it more than 45 degrees.
Item Probable cause of malfunc-
tion and check Maintenance jobConfirmation of service
completion
1 Connection of lean angle sensor coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 2.
2 Connection of wire harness ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness. Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 3.
3 Wire harness continuity. Open or short circuit  Re-
place the wire harness.
Between lean angle sensor
coupler and ECU coupler.
blue–blue
yellow/green–yellow/green
black/blue–black/blue Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 4.
4 Defective lean angle sensor. Execute the diagnostic mode. (Code No. 08)
Replace if defective.
Refer to “CHECKING THE
LEAN ANGLE SENSOR” on
page 9-75.Push the start switch.
Fault code number is not dis-
played
 Service is finished.
Fault code number is dis-
played  Go to item 5.
5 Malfunction in ECU. Replace the ECU.

ELECTRICAL COMPONENTS
9-63
1. Intake air temperature sensor
2. Intake air pressure sensor
3. Throttle position sensor
4. Starter relay
5. Main fuse
6. Headlight relay
7. Starting circuit cut-off relay
8. Lean angle sensor
9. Radiator fan motor fuse
10.Radiator fan motor relay
11.Main relay
12.Coolant temperature sensor

ELECTRICAL COMPONENTS
9-74
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester ( 1k) to the
spark plug cap.
b. Measure the spark plug cap resistance.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1391CHECKING THE IGNITION COIL
1. Disconnect: • Ignition coil terminal(from the sub wire harness)
• Spark plug cap (from the ignition coil)
2. Check:
• Primary coil resistanceOut of specification  Replace.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester (  1) to the igni-
tion coil. b. Measure the primary coil resistance.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
3. Check:
• Secondary coil resistanceOut of specification  Replace.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester (  1k) to the ig-
nition coil.
b. Measure the secondary coil resistance.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1392CHECKING THE CRANKSHAFT POSITION
SENSOR
1. Disconnect: • Crankshaft position sensor coupler(from the wire harness)
2. Check:
• Crankshaft position sensor resistanceOut of specification  Replace.
Pocket tester
90890-03112
Analog pocket tester YU-03112-C
Primary coil resistance 2.16–2.64 
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
• Positive tester probe 
Ignition coil terminal 1 “1”
• Negative tester probe 
Ignition coil terminal 2 “2”
Secondary coil resistance 8.64–12.96 k 
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
• Positive tester probe  Ignition coil terminal 1 “1”
• Negative tester probe 
Spark plug lead “2”

ELECTRICAL COMPONENTS
9-75
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester ( 100) to the
crankshaft position sensor coupler.
b. Measure the crankshaft position sensor re- sistance.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1393CHECKING THE LEAN ANGLE SENSOR
1. Remove:• Lean angle sensor
(from the bracket)
2. Check: • Lean angle sensor output voltage
Out of specification  Replace.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the lean angle sensor coupler to
the wire harness.
b. Connect the pocket tester (DC 20 V) to the
lean angle sensor coupler as shown. c. Incline the lean angle sensor.
d. Measure the lean angle sensor output volt-
age.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1394CHECKING THE STARTER MOTOR OPERA-
TION
1. Check:• Starter motor operation
Does not operate  Perform the electric
starting system troubleshooting, starting
with step 4.
Refer to “ELECTRIC STARTING SYSTEM”
on page 9-6.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the positive battery terminal “1” and starter motor lead “2” with a jumper lead “3”.
EWA
WARNING
• A wire that is used as a jumper lead must
have at least the same capacity of the bat-
tery lead, otherwise the jumper lead may
burn.
• This check is likely to produce sparks, therefore, make sure no flammable gas or
fluid is in the vicinity.
Crankshaft position sensor resis-
tance
228–342 
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
• Positive tester probe 
Gray “1”
• Negative tester probe 
Black “2”
Lean angle sensor output voltageOperating angle45 °
Output voltage up to operating
angle 3.7–4.4 V
Output voltage over operating an-
gle 0.4–1.4 V
12
Gy B
Pocket tester90890-03112
Analog pocket tester YU-03112-C
Test harness– lean angle sensor
(6P) 90890-03209
Test harness– lean angle sensor
(6P) YU-03209
• Positive tester probe  Yellow/Green “1”
• Negative tester probe 
Black/Blue “2”
2
1
Ã45
Ã
45

ELECTRICAL COMPONENTS
9-77
EAS2GC1396CHECKING THE SPEED SENSOR
1. Check:• Speed sensor output voltageOut of specification  Replace.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the test harness-speed sensor (3P)
to the speed sensor coupler and wire har-
ness.
b. Connect the pocket tester (DC20V) to the test harness-speed sensor (3P).
c. Push the start switch.
d. Elevate the front wheel and slowly turn it.
e. Measure the voltage (DC 5 V) of white and black/white. With the front wheel slowly ro-
tating, voltage alternates between 0 V and 5
V.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1397CHECKING THE FUEL SENDER
1. Drain the gasoline.
2. Disconnect:• Fuel sender coupler
(from the fuel sender)
3. Remove:
• Fuel sender(from the fuel tank) 4. Check:
• Fuel sender resistanceOut of specification  Replace the fuel
sender.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester (  1k) to the
fuel sender as shown.
b. Measure the resistance of the fuel sender.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
EAS2GC1398CHECKING THE RESISTER
1. Disconnect: • Resister coupler(from the wire harness)
2. Check: • Resister resistanceOut of specification  Replace the resister.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester (  10) to the re-
sister as shown.
Output voltage reading cycle
0.6V to 4.8V to 0.6V to 4.8V
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
Test harness– speed sensor 5TJ
(3P) 90890-03228
Test harness– speed sensor 5TJ
(3P) YU-03228
• Positive tester probe  White “1”
• Negative tester probe 
Black “2”
BRW
21
Fuel sender resistance
1.35–1.90 k  at 25°C (77°F)
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
• Positive tester probe  Green “1”
• Negative tester probe 
Black “2”
Resister resistance64.6–71.4 
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
1
2