
CHARGING SYSTEM
9-14
EAS2GBB364TROUBLESHOOTING
The battery is not being charged.
TIP
Before troubleshooting, remove the following part (s):
1. Seat
2. Side cover (left/right)
1. 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 stator coil.
Refer to “CHECKING THE STA-
TOR COIL” on page 9-76.NG
Replace the stator assembly.
OK
4. Check the rectifier/regulator.
Refer to “CHECKING THE RECTI-
FIER/REGULATOR” on page 9-76.NG
Replace the rectifier/regulator.
OK
5. Check the entire charging system’s
wiring.
Refer to “CIRCUIT DIAGRAM” on
page 9-12.NG
Properly connect or repair the charging
system’s wiring.
OK
This circuit is OK.

FUEL INJECTION SYSTEM
9-30
EAS2GBB374ECU SELF-DIAGNOSTIC FUNCTION
The ECU is equipped with a self-diagnostic function in order to ensure that the fuel injection system
is operating normally. If this function detects a malfunction in the system, it immediately operates the
engine under substitute characteristics and illuminates the engine trouble warning light to alert the
rider that a malfunction has occurred in the system. Once a malfunction has been detected, a fault
code number is stored in the memory of the ECU.
• To inform the rider that the fuel injection system is not functioning, the engine trouble warning light
flashes while the start switch is being pushed to start the engine.
• If a malfunction is detected in the system by the self-diagnostic function, the ECU provides an ap-
propriate substitute characteristic operation, and alerts the rider of the detected malfunction by illu-
minating the engine trouble warning light.
Engine trouble warning light indication and fuel injection system operation
* The warning light flashes when any one of the following conditions is present and the start switch
is pushed:
Checking the engine trouble warning light
The engine trouble warning light comes on for around 2 seconds when pushing the start switch to
turn on the meter light and the engine trouble warning light comes on while the start switch is being
pushed.Warning light indica-
tionECU operationFuel injection opera-
tionVehicle operation
Flashing* Warning provided
when unable to start
engineOperation stopped Cannot be operated
Remains on Malfunction detected Operated with substi-
tute characteristics in
accordance with the
description of the mal-
functionCan or cannot be oper-
ated depending on the
fault code
12: Crankshaft position sensor 41: Lean angle sensor
(open or short circuit)
30: Lean angle sensor
(latch up detected)50: ECU internal malfunction
(faulty ECU memory)
33: Ignition coil
(Malfunction detected in the primary wire
of the ignition coil)
a. The meter light does not come on.
b. The meter light comes on.
c. Light OFF
d. Light ON for 2 seconds
ab
cdc

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
ItemIgnition coil: open or short circuit detected in the primary lead
of the ignition coil.
Fail-safe systemUnable to start engine
Unable to drive vehicle
Diagnostic code No.30
ActuationActuates 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.
ProcedureCheck that a spark is generated five times.
• Connect an ignition checker.
ItemProbable cause of malfunc-
tion and checkMaintenance 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–orangeStart 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
(Code No. 30).
No spark Replace the
ECU. Fault code No. 33
ItemIgnition coil: open or short circuit detected in the primary lead
of the ignition coil.

ELECTRICAL COMPONENTS
9-67
EAS27990CHECKING THE BULBS AND BULB SOCK-
ETS
TIP
Do not check any of the lights that use LEDs.
Check each bulb and bulb socket for damage
or wear, proper connections, and also for con-
tinuity between the terminals.
Damage/wear Repair or replace the bulb,
bulb socket or both.
Improperly connected Properly connect.
No continuity Repair or replace the bulb,
bulb socket or both.
Types of bulbs
The bulbs used on this vehicle are shown in the
illustration on the left.
• Bulbs “a” and “b” are used for the headlights
and usually use a bulb holder that must be de-
tached before removing the bulb. The majority
of these types of bulbs can be removed from
their respective socket by turning them coun-
terclockwise.
• Bulbs “c” is used for turn signal and can be re-
moved from the socket by pushing and turn-
ing the bulb counterclockwise.
Checking the condition of the bulbs
The following procedure applies to all of the
bulbs.
1. Remove:
•Bulb
EWA
WARNING
Since the headlight bulb gets extremely hot,
keep flammable products and your hands
away from the bulb until it has cooled down.
ECA
NOTICE
• Be sure to hold the socket firmly when re-
moving the bulb. Never pull the lead, oth-
erwise it may be pulled out of the terminal
in the coupler.
• Avoid touching the glass part of the head-
light bulb to keep it free from oil, otherwise
the transparency of the glass, the life of
the bulb, and the luminous flux will be ad-
versely affected. If the headlight bulb gets
soiled, thoroughly it with a cloth moist-
ened with alcohol or lacquer thinner.
2. Check:
• Bulb (for continuity)
(with the pocket tester)
No continuity Replace.
TIP
Before checking for continuity, set the pocket
tester to “0” and to the “ 1” range.
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a. Connect the positive tester probe to terminal
“1” and the negative tester probe to terminal
“2”, and check the continuity.
b. Connect the positive tester probe to terminal
“1” and the negative tester probe to terminal
“3”, and check the continuity.
c. If either of the readings indicate no continu-
ity, replace the bulb.
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Pocket tester
90890-03112
Analog pocket tester
YU-03112-C

ELECTRICAL COMPONENTS
9-69
4. Install:
• Seat
• Side cover (left/right)
Refer to “GENERAL CHASSIS” on page 5-
1.
EAS2GBB385CHECKING 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)
• Seat
Refer 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
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
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
9-74
e. Crank the engine by pushing the start switch
and gradually increase the spark gap until a
misfire occurs.
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EAS2GBB389CHECKING THE SPARK PLUG CAP
1. Remove:
• Spark plug cap
(from the spark plug lead)
2. Check:
• Spark plug cap resistance
Out of specification Replace.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester ( 1k) to the
spark plug cap.
b. Measure the spark plug cap resistance.
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EAS2GBB390CHECKING THE IGNITION COIL
1. Disconnect:
• Ignition coil terminal
(from the sub wire harness)
• Spark plug cap
(from the ignition coil)
2. Check:
• Primary coil resistance
Out of specification Replace.
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a. Connect the pocket tester ( 1) to the igni-
tion coil.b. Measure the primary coil resistance.
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3. Check:
• Secondary coil resistance
Out of specification Replace.
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a. Connect the pocket tester ( 1k) to the ig-
nition coil.
b. Measure the secondary coil resistance.
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Resistance
7.50–12.50 k
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
9-76
CHECKING 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.
b. Check the starter motor operation.
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EAS28150CHECKING THE STATOR COIL
1. Disconnect:
• Stator coil coupler
(from the wire harness)
2. Check:
• Stator coil resistance
Out of specification Replace the stator
coil.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Connect the pocket tester ( 1) to the sta-
tor coil coupler as shown.b. Measure the stator coil resistance.
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EAS2GBB394CHECKING THE RECTIFIER/REGULATOR
1. Check:
• Charging voltage
Out of specification Replace the rectifier/
regulator.
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Set the digital tachometer to the ignition coil.
b. Connect the pocket tester (DC 20 V) to the
rectifier/regulator coupler as shown. Stator coil resistance
0.528–0.792 (W–W)
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
• Positive tester probe
White “1”
• Negative tester probe
White “2”
• Positive tester probe
White “1”
• Negative tester probe
White “3”
• Positive tester probe
White “2”
• Negative tester probe
White “3”
Regulated voltage (DC)
14.1–14.9 V
Digital tachometer
90890-06760
Digital tachometer
YU-39951-B
Pocket tester
90890-03112
Analog pocket tester
YU-03112-C
• Positive tester probe
Red “1”
• Negative tester probe
Black “2”
123