2016 YAMAHA WR 450F battery

ELECTRICAL COMPONENTS
9-61
1. Rectifier/regulator
2. Clutch switch
3. Ignition coil
4. ECU (engine control unit)
5. Fuel sender
6. Fuel pump
7. Battery
8. Resistor
9. Neutral switch
10.Radiator fan motor
11.Injector

ELECTRICAL COMPONENTS
9-69
4. Install:• Seat
• Side cover (left/right)Refer to “GENERAL CHASSIS” on page 5-
1.
EAS2GC1386CHECKING AND CHARGING THE BATTERYEWA
WARNING
Batteries generate explosive hydrogen gas
and contain electrolyte which is made of
poisonous and highly caustic sulfuric acid.
Therefore, always follow these preventive
measures:
• Wear protective eye gear when handling or working near batteries.
• Charge batteries in a well-ventilated area.
• Keep batteries away from fire, sparks or
open flames (e.g., welding equipment,
lighted cigarettes).
• DO NOT SMOKE when charging or han- dling batteries.
• KEEP BATTERIES AND ELECTROLYTE
OUT OF REACH OF CHILDREN.
• Avoid bodily contact with electrolyte as it can cause severe burns or permanent eye
injury.
FIRST AID IN CASE OF BODILY CONTACT:
EXTERNAL
• Skin — Wash with water.
• Eyes — Flush with water for 15 minutes and get immediate medical attention.
INTERNAL
• Drink large quantities of water or milk fol-
lowed with milk of magnesia, beaten egg
or vegetable oil. Get immediate medical at-
tention.
ECA
NOTICE
• This is a VRLA (Valve Regulated Lead Ac-id) battery. Never remove the sealing caps
because the balance between cells will not
be maintained and battery performance
will deteriorate.
• Charging time, charging amperage and charging voltage for a VRLA (Valve Regu-
lated Lead Acid) battery are different from
those of conventional batteries. The VRLA
(Valve Regulated Lead Acid) battery
should be charged according to the appro-
priate charging method. If the battery is
overcharged, the electrolyte level will drop
considerably. Therefore, take special care
when charging the battery.
TIP
Since VRLA (Valve Regulated Lead Acid) bat-
teries are sealed, it is not possible to check the
charge state of the battery by measuring the
specific gravity of the electrolyte. Therefore, the
charge of the battery has to be checked by
measuring the voltage at the battery terminals.
1. Remove:• Side cover (left/right)
• SeatRefer to “GENERAL CHASSIS” on page 5-
1.
2. Disconnect: • Battery leads
(from the battery terminals)
ECA
NOTICE
First, disconnect the negative battery lead
“1”, and then positive battery lead “2”.
3. Remove:• Battery
4. Check: • Battery charge
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a. Connect a pocket tester to the battery termi- nals.
TIP
• The charge state of a VRLA (Valve Regulated Lead Acid) battery can be checked by mea-
suring its open-circuit voltage (i.e., the voltage
when the positive battery terminal is discon-
nected).
• No charging is necessary when the open-cir-
cuit voltage equals or exceeds 12.8 V.
b. Check the charge of the battery, as shown in the charts and the following example.
• Positive tester probe 
positive battery terminal
• Negative tester probe 
negative battery terminal
1
2

ELECTRICAL COMPONENTS
9-70
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5. Charge:• Battery
(refer to the appropriate charging method)
EWA
WARNING
Do not quick charge a battery.
ECA
NOTICE
• Do not use a high-rate battery charger since it forces a high-amperage current
into the battery quickly and can cause bat-
tery overheating and battery plate dam-
age.
• If it is impossible to regulate the charging current on the battery charger, be careful
not to overcharge the battery. • When charging a battery, be sure to re-
move it from the vehicle. (If charging has
to be done with the battery mounted on the
vehicle, disconnect the negative battery
lead from the battery terminal.)
• To reduce the chance of sparks, do not
plug in the battery charger until the battery
charger leads are connected to the bat-
tery.
• Before removing the battery charger lead clips from the battery terminals, be sure to
turn off the battery charger.
• Make sure the battery charger lead clips are in full contact with the battery terminal
and that they are not shorted. A corroded
battery charger lead clip may generate
heat in the contact area and a weak clip
spring may cause sparks.
• If the battery becomes hot to the touch at
any time during the charging process, dis-
connect the battery charger and let the
battery cool before reconnecting it. Hot
batteries can explode!
• As shown in the following illustration, the open-circuit voltage of a VRLA (Valve Reg-
ulated Lead Acid) battery stabilizes about
30 minutes after charging has been com-
pleted. Therefore, wait 30 minutes after
charging is completed before measuring
the open-circuit voltage.
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Charging method using a variable-cur-
rent (voltage) charger
a. Measure the open-circuit voltage prior to charging.
TIP
Voltage should be measur ed 30 minutes after
the engine is stopped.
Example
Open-circuit voltage = 12.0 V
Charging time = 6.5 hours
Charge of the battery = 20–30%
A. Open-circuit voltage (V)
B. Charging time (hours)
C. Relationship between the open-circuit voltage
and the charging time at 20°C (68°F)
D. These values vary wit h the temperature, the
condition of the battery plates, and the electro-
lyte level.
A. Open-circuit voltage (V)
B. Charging condition of the battery (%)
C. Ambient temperature 20°C (68°F)
A. Open-circuit voltage (V)
B. Time (minutes)
C. Charging
D. Ambient temperature 20°C (68°F)
E. Check the open-circuit voltage.

ELECTRICAL COMPONENTS
9-71
b. Connect a charger and ammeter to the bat-tery and start charging.
TIP
Set the charging voltage to 16–17 V. If the set-
ting is lower, charging will be insufficient. If too
high, the battery will be over-charged.
c. Make sure that the current is higher than the standard charging current written on the bat-
tery.
TIP
If the current is lower than the standard charg-
ing current written on the battery, set the charg-
ing voltage adjust dial at 20–24 V and monitor
the amperage for 3–5 minutes to check the bat-
tery.
d. Adjust the voltage so that the current is at
the standard charging level.
e. Set the time according to the charging time suitable for the open-circuit voltage.
f. If charging requires more than 5 hours, it is advisable to check the charging current after
a lapse of 5 hours. If there is any change in
the amperage, readjust the voltage to obtain
the standard charging current.
g. Measure the battery open-circuit voltage af-
ter leaving the battery unused for more than
30 minutes.
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Charging method using a constant volt-
age charger
a. Measure the open-circuit voltage prior to charging.
TIP
Voltage should be measured 30 minutes after
the engine is stopped.
b. Connect a charger and ammeter to the bat-tery and start charging.
c. Make sure that the current is higher than the
standard charging current written on the bat-
tery.
TIP
If the current is lower than the standard charg-
ing current written on the battery, this type of
battery charger cannot charge the VRLA (Valve
Regulated Lead Acid) battery. A variable volt-
age charger is recommended.
d. Charge the battery until the battery’s charg-ing voltage is 15 V.
TIP
Set the charging time at 20 hours (maximum).
e. Measure the battery open-circuit voltage af-ter leaving the battery unused for more than
30 minutes.
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6. Install:
• Battery terminals
7. Connect:
• Battery leads(to the battery terminals)
ECA
NOTICE
First, connect the positive battery lead “1”,
and then the negative battery lead “2”.
8. Check:• Battery terminalsDirt  Clean with a wire brush.
Loose connection  Connect properly.
9. Lubricate: • Battery terminals
10.Install: • Seat
• Side cover (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
• Standard charging current is reached
Battery is good.
• Standard charging current is not reached Replace the battery.
12.8 V or more --- Charging is complete.
12.7 V or less --- Recharging is required.
Under 12.0 V --- Replace the battery.
12.8 V or more --- Charging is complete.
12.7 V or less --- Recharging is required.
Under 12.0 V --- Replace the battery.
Recommended lubricantDielectric grease
2
1

ELECTRICAL COMPONENTS
9-72
EAS2GC1387CHECKING THE RELAYS
Check each switch for continuity with the pock-
et tester. If the continuity reading is incorrect,
replace the relay.
1. Disconnect the relay from the wire harness.
2. Connect the pocket tester ( 1) and bat-
tery (12 V) to the relay terminal as shown.
Check the relay operation.
Out of specification  Replace.
Starter relay
Main relay Starting circuit cut-off relay
Headlight relay
Radiator fan motor relay
Pocket tester
90890-03112
Analog pocket tester YU-03112-C
1. Positive battery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
1. Positive battery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
21
3
4
R/WBr/WR/YL/G
1
2 3
4
L/R BrR
R,R/W
1. Positive ba ttery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
1. Positive ba ttery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
Result
Continuity
(between “3” to “4”)
1. Positive ba ttery terminal
2. Negative ba ttery terminal
3. Positive tester probe
4. Negative tester probe
1
2 3
4
G/B L/B
L/G,L/W
1
2 3
4
R,R/Y
G R
1
2 3
4
P/L R/L
R/W
Br,R/W

ELECTRICAL COMPONENTS
9-75
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a. Connect the pocket tester ( 100) to the
crankshaft position sensor coupler.
b. Measure the crankshaft position sensor re- sistance.
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EAS2GC1393CHECKING THE LEAN ANGLE SENSOR
1. Remove:• Lean angle sensor
(from the bracket)
2. Check: • Lean angle sensor output voltage
Out of specification  Replace.
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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.
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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.
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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
9-78
b. Measure the resistance of the resister.
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EAS2GC1399CHECKING THE RADIATOR FAN MOTOR
1. Check:• Radiator fan motor
Faulty/rough movement  Replace.
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a. Disconnect the radiator fan motor coupler
from the wire harness.
b. Connect the battery (DC 12 V) as shown.
c. Measure the radiator fan motor movement.
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EAS2GC1400CHECKING THE COOLANT TEMPERATURE
SENSOR
1. Remove: • Coolant temperature sensor
EWA
WARNING
• Handle the coolant temperature sensor with special care.
• Never subject the coolant temperature sensor to strong shocks. If the coolant
temperature sensor is dropped, replace it. 2. Check:
• Coolant temperature sensor resistanceOut of specification  Replace.
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a. Connect the pocket tester (  1k/100) to
the coolant temperature sensor.
b. Immerse the coolant temperature sensor in a container filled with coolant.
TIP
Make sure the coolant temperature sensor ter-
minals do not get wet.
c. Place a thermometer in the coolant.
d. Slowly heat the coolant, and then let it cool to the specified temperature indicated in the
table.
e. Check the coolant temperature sensor for continuity at the temperatures indicated in
the table.
• Positive tester probe 
Black “1”
• Negative tester probe 
Black “2”
• Positive battery terminal 
Blue “1”
• Negative battery terminal 
Black “2”
1
2
12
12V
LB
Coolant temperature sensor re-
sistance 2512–2777  at 20 °C (2512–
2777  at 68 °F)
210–220  at 100 °C (210–220 
at 212 °F)
Pocket tester 90890-03112
Analog pocket tester YU-03112-C
• Positive tester probe  Green/White “1”
• Negative tester probe 
Black/Blue “2”
12
G/W B/L
B/LG/W

TROUBLESHOOTING
10-1
EAS2GC1406
TROUBLESHOOTING
EAS2GC1407GENERAL INFORMATION
TIP
The following guide for troubleshooting does
not cover all the possible causes of trouble. It
should be helpful, however, as a guide to basic
troubleshooting. Refer to the relative procedure
in this manual for checks, adjustments, and re-
placement of parts.
EAS2GC1408STARTING FAILURES
Engine
1. Cylinder and cylinder head• Loose spark plug
• Loose cylinder head or cylinder
• Damaged cylinder head gasket
• Damaged cylinder gasket
• Worn or damaged cylinder
• Incorrect valve clearance
• Improperly sealed valve
• Incorrect valve-to-valve-seat contact
• Incorrect valve timing
• Faulty valve spring
• Seized valve
2. Piston and piston ring(s) • Improperly installed piston ring
• Damaged, worn or fatigued piston ring
• Seized piston ring
• Seized or damaged piston
3. Air filter • Improperly installed air filter
• Clogged air filter element
4. Crankcase and crankshaft • Improperly assembled crankcase
• Seized crankshaft
Fuel system
1. Fuel tank • Empty fuel tank
• Clogged fuel tank breather hose
• Deteriorated or contaminated fuel
• Clogged or damaged fuel hose
2. Fuel pump
• Faulty fuel pump
3. Throttle body • Deteriorated or contaminated fuel
• Sucked-in air Electrical system
1. Battery
• Discharged battery
• Faulty battery
2. Fuse • Blown, damaged or incorrect fuse
• Improperly installed fuse
3. Spark plug • Incorrect spark plug gap
• Incorrect spark plug heat range
• Fouled spark plug
• Worn or damaged electrode
• Worn or damaged insulator
4. Ignition coil • Cracked or broken ignition coil body
• Broken or shorted primary or secondary coils
5. Ignition system • Faulty ECU
• Faulty crankshaft position sensor
• Broken generator rotor woodruff key
6. Switches and wiring
• Faulty ECU
• Faulty engine stop switch
• Broken or shorted wiring
• Faulty neutral switch
• Improperly grounded circuit
• Loose connections
7. Starting system • Faulty starter motor
• Faulty starter relay
• Faulty starting circuit cut-off relay
• Faulty starter clutch
EAS2GC1409INCORRECT ENGINE IDLING SPEED
Engine
1. Cylinder and cylinder head• Incorrect valve clearance
• Damaged valve train components
2. Air filter • Clogged air filter element
Fuel system
1. Throttle body • Damaged or loose throttle body joint
• Improperly synchronized throttle bodies
• Improper throttle cable free play
• Flooded throttle body