2020 YAMAHA MT-03 Owners Manual

Periodic maintenance and adjustment
6-29
6
EAU23292
Checking the wheel bearings
The front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
EAU50583
Battery
The battery is located under the rider
seat. It is a VRLA (valve-regulated lead-
acid) battery. There is no need to check
the electrolyte or to add distilled water.
However, the battery lead connections
need to be checked, and tightened if
necessary.
WARNING
EWA10761
Electrolyte is poisonous and
dangerous since it contains sul-
furic acid, which causes severe
burns. Avoid any contact with
skin, eyes or clothing and al-
ways shield your eyes when
working near batteries. In case
of contact, administer the fol-
lowing FIRST AID.
EXTERNAL: Flush with plenty
of water.
INTERNAL: Drink large quan-
tities of water or milk and im-
mediately call a physician.
EYES: Flush with water for 15
minutes and seek prompt
medical attention.
1. Battery
2. Negative battery lead (black)
3. Positive battery lead (red)
1
2
3
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Periodic maintenance and adjustment
6-30
6Batteries produce explosive hy-
drogen gas. Therefore, keep
sparks, flames, cigarettes, etc.,
away from the battery and pro-
vide sufficient ventilation when
charging it in an enclosed
space.
KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
NOTICE
ECA10621
Never attempt to remove the battery
cell seals, as this would permanently
damage the battery.
To charge the battery
Have your Yamaha dealer charge the
battery if it seems to have discharged.
Keep in mind that the battery tends to
discharge more quickly if the vehicle is
equipped with optional electrical ac-
cessories.
NOTICE
ECA16522
To charge a VRLA (Valve Regulated
Lead Acid) battery, a special (con-
stant-voltage) battery charger is re-
quired. Using a conventional battery
charger will damage the battery.
To store the battery
1. If the vehicle will not be used for
more than one month, remove the
battery, fully charge it, and then
place it in a cool, dry place.
NOTICE: When removing the
battery, be sure to turn the main
switch off, then disconnect the
negative lead before discon-
necting the positive lead.
[ECA16304]
2. If the battery will be stored for
more than two months, check it at
least once a month and fully
charge it if necessary.
3. Fully charge the battery before in-
stallation. NOTICE: When install-
ing the battery, be sure to turn
the main switch off, then con-
nect the positive lead before
connecting the negative lead.
[ECA16842]
4. After installation, make sure that
the battery leads are properly con-
nected to the battery terminals.
NOTICE
ECA16531
Always keep the battery charged.
Storing a discharged battery can
cause permanent battery damage.
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Periodic maintenance and adjustment
6-31
6
EAU62776
Replacing the fuses
The main fuse is located under the
passenger seat. The fuse box, which
contains the fuses for the individual cir-
cuits, is located behind the center pan-
el.
To access the main fuse, proceed as
follows.
1. Remove the passenger seat. (See
page 3-17.)
2. Remove the tray by removing the
quick fasteners.
3. Pull back the starter relay cover.
4. Disconnect the starter relay cou-
pler by pressing from both sides.5. Connect the starter relay coupler,
and then slide the cover to its orig-
inal position.
6. Place the tray in its original posi-
tion, and then install the quick fas-
teners.
7. Install the passenger seat.
TIP
To access the fuse box, remove the
center cover. (See page 3-17.)
1. Quick fastener
2. Tray
1. Starter relay cover
2. Starter relay coupler
3. Main fuse
4. Spare main fuse
2
1
1
2
3
4
1. Fuse box
1. Ignition fuse
2. Signaling system fuse
3. ABS control unit fuse
4. Headlight fuse
5. Backup fuse (for clock)
6. Radiator fan motor fuse
7. Spare fuse
1
71
2
3
5
6
4
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Periodic maintenance and adjustment
6-32
6
If a fuse is blown, replace it as follows.
1. Turn the main switch off and turn
off the electrical circuit in ques-
tion.
2. Remove the blown fuse, and then
install a new fuse of the specified
amperage. WARNING! Do not
use a fuse of a higher amperage
rating than recommended to
avoid causing extensive dam-
age to the electrical system and
possibly a fire.
[EWA15132]
3. Turn the main switch on and turn
on the electrical circuit in question
to check if the device operates.
4. If the fuse immediately blows
again, have a Yamaha dealer
check the electrical system.
1. Fuse box 2
1. Spare fuse
2. ABS solenoid fuse
3. ABS motor fuse
1
123
Specified fuses:
Main fuse:
30.0 A
Headlight fuse:
7.5 A
Signaling system fuse:
15.0 A
Ignition fuse:
15.0 A
Radiator fan motor fuse:
7.5 A
ABS motor fuse:
30.0 A
ABS solenoid fuse:
15.0 A
ABS control unit fuse:
7.5 A
Backup fuse:
7.5 A
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Periodic maintenance and adjustment
6-33
6
EAU80380
Vehicle lights
Except for the license plate light bulb,
this model’s lights are all LED.
If an LED light does not come on,
check the fuses and then have a
Yamaha dealer check the vehicle. If the
license plate light does not come on,
check and replace the bulb. (See page
6-33.)
NOTICE
ECA16581
Do not affix any type of tinted film or
stickers to the headlight lens.
EAU62670
Replacing the license plate
light bulb
1. Remove the mudguard by remov-
ing the quick fasteners.
2. Remove the rear fender lower
panel by removing the bolts and
screws.
3. Remove the license plate light
bulb socket (together with the
bulb) by pulling it out.
4. Remove the burnt-out bulb by
pulling it out.
1. Headlight (high beam)
2. Headlight (low beam)
3. Auxiliary light
3
12
1. Mudguard
2. Quick fastener
1. Bolt
2. Screw
3. Rear fender lower panel
1
2
3
2
1
2
2 1
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Periodic maintenance and adjustment
6-34
65. Insert a new bulb into the socket.
6. Install the socket (together with
the bulb) by pushing it in.
7. Install the rear fender lower panel
by installing the bolts and screws.
8. Install the mudguard by installing
the quick fasteners.
EAU24351
Supporting the motorcycle
Since this model is not equipped with a
centerstand, follow these precautions
when removing the front and rear
wheel or performing other mainte-
nance requiring the motorcycle to
stand upright. Check that the motorcy-
cle is in a stable and level position be-
fore starting any maintenance. A
strong wooden box can be placed un-
der the engine for added stability.
To service the front wheel
1. Stabilize the rear of the motorcy-
cle by using a motorcycle stand
or, if an additional motorcycle
stand is not available, by placing a
jack under the frame in front of the
rear wheel.
2. Raise the front wheel off the
ground by using a motorcycle
stand.
To service the rear wheel
Raise the rear wheel off the ground by
using a motorcycle stand or, if a motor-
cycle stand is not available, by placing
a jack either under each side of the
frame in front of the rear wheel or under
each side of the swingarm.
1. License plate light bulb
2. License plate light bulb socket
2
1
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Periodic maintenance and adjustment
6-35
6
EAU25872
Troubleshooting
Although Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting charts
represent quick and easy procedures
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checking the fuel system, do
not smoke, and make sure there are
no open flames or sparks in the ar-
ea, including pilot lights from water
heaters or furnaces. Gasoline or
gasoline vapors can ignite or ex-
plode, causing severe injury or prop-
erty damage.
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Periodic maintenance and adjustment
6-36
6
EAU86390
Troubleshooting chart
1. FuelThere is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine turns over
quickly.
The engine turns over
slowly.
Try starting the
engine.
The engine does not
start.
Check the battery.
Wipe off with a dry
cloth and correct the
spark plug gap, or
replace the spark
plug(s).
Check the battery
lead connections,
and charge the
battery if necessary.
2. BatteryThe battery is good.
The engine does not
start.
Check the ignition.
3. IgnitionWet
Dry
There is compression.
There is no
compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.
Have a Yamaha dealer check the vehicle.
The engine does not
start.
Check the
compression.Have a Yamaha
dealer check the
vehicle.
Remove the spark
plug and check
the electrodes.
Operate the electric
starter.
Try starting the
engine.
Check the fuel level
in the fuel tank.
4. Compression
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