check engine light YAMAHA MT-125 2020 Owners Manual

Table of contents
Safety information............................1-1
Description........................................2-1
Left view ..........................................2-1
Right view........................................2-2
Controls and instruments ................2-3
Instrument and control functions....3-1
Main switch/steering lock ...............3-1
Indicator lights and warning
lights ............................................3-2
Multi-function meter unit .................3-4
Handlebar switches.......................3-12
Clutch lever ...................................3-13
Shift pedal .....................................3-13
Brake lever ....................................3-14
Brake pedal ...................................3-14
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-16
Fuel tank overflow hose ................3-18
Catalytic converter ........................3-18
Seat ...............................................3-19
Helmet holder ................................3-20
Sidestand ......................................3-20
Ignition circuit cut-off system........3-21
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Engine break-in ...............................5-1
Starting the engine ..........................5-2
Shifting ............................................5-4
Tips for reducing fuel
consumption ................................5-5
Parking ............................................5-6
Periodic maintenance and
adjustment........................................6-1
Tool kit.............................................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4Removing and installing
cowlings ...................................... 6-7
Checking the spark plug ................. 6-7
Engine oil and oil filter element ....... 6-8
Why Yamalube .............................. 6-11
Coolant ......................................... 6-11
Replacing the air filter element
and cleaning the check hose..... 6-13
Adjusting the engine idling
speed......................................... 6-13
Adjusting the throttle grip free
play ............................................ 6-14
Valve clearance ............................. 6-15
Tires .............................................. 6-15
Cast wheels .................................. 6-18
Adjusting the clutch lever free
play ............................................ 6-18
Checking the front brake lever
free play ..................................... 6-19
Adjusting the brake pedal free
play ............................................ 6-20
Brake light switches ...................... 6-20
Checking the front and rear brake
pads........................................... 6-21
Checking the brake fluid level....... 6-22
Changing the brake fluid............... 6-23
Drive chain slack ........................... 6-23
Cleaning and lubricating the drive
chain .......................................... 6-25
Checking and lubricating the
cables ........................................ 6-25
Checking and lubricating the
throttle grip and cable ............... 6-26
Checking and lubricating the
brake and shift pedals ............... 6-26
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
sidestand ................................... 6-27
Lubricating the swingarm pivots... 6-28
Checking the front fork ................. 6-28
Checking the steering ................... 6-29
Checking the wheel bearings ....... 6-29
Battery .......................................... 6-30
Replacing the fuses ...................... 6-31
Vehicle lights ................................. 6-32
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Safety information
1-5
1 operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires and Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. See page 6-15
for tire specifications and for informa-
tion on servicing and replacing your
tires.
Transporting the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle.
Remove all loose items from the
motorcycle.
Check that the fuel cock (if
equipped) is in the off position and
that there are no fuel leaks.
Shift the transmission into gear
(for models with a manual trans-
mission).
Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mountedhandlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Instrument and control functions
3-3
3 For vehicles with a radiator fan, the ra-
diator fan(s) automatically switch on or
off according to the coolant tempera-
ture.
TIP
When the vehicle is turned on, the light
will come on for a few seconds, and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle.
NOTICE
ECA10022
Do not continue to operate the en-
gine if it is overheating.
EAU73172Engine trouble warning light “ ”
This warning light comes on if a prob-
lem is detected in the engine or other
vehicle control system. If this occurs,
have a Yamaha dealer check the on-
board diagnostic system.
TIP
When the vehicle is turned on, the light
will come on for a few seconds and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle.
EAU69895ABS warning light “ ”
This warning light comes on when the
vehicle is first turned on, and goes off
after starting riding. If the warning light
comes on while riding, the anti-lock
brake system may not work correctly.
WARNING
EWA16043
If the ABS warning light does not
turn off after reaching 10 km/h (6
mi/h), or if the warning light comes
on while riding:
Use extra caution to avoid pos-
sible wheel lock during emer-
gency braking.
Have a Yamaha dealer check
the vehicle as soon as possible.
EAU80372Shift light
This light can be set to come on and go
off at select engine speeds. (See page
3-9.)
TIP
When the vehicle is turned on, the light
will come on for a few seconds and
then go off. If the light does not come
on, have a Yamaha dealer check the
vehicle.
ABS
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Instrument and control functions
3-11
3 To set the user name
1. Turn the key to “ ”.
2. Push and hold the “RESET” but-
ton.
3. Turn the key to “ ”, and then re-
lease the “RESET” button after
four seconds.
4. When the first character starts
flashing, push the “SELECT” but-
ton to display the next alpha nu-
merical character, push the
“RESET” button to switch to the
previous character.
5. Push and hold the “SELECT” but-
ton to confirm the selected char-
acter. The second character will
start flashing. Repeat this process
for all six characters. After the
sixth character is set, all charac-
ters will flash twice and the setting
mode will automatically end.Self-diagnosis device
This model is equipped with a self-di-
agnosis device for various electrical
circuits.
If a problem is detected in any of those
circuits, the engine trouble warning
light will come on and the display will
indicate an error code.
If the display indicates any error codes,
note the code number, and then have a
Yamaha dealer check the vehicle.
NOTICE
ECA11591
If the display indicates an error
code, the vehicle should be checked
as soon as possible in order to avoid
engine damage.
1. Hyphen
2. Space
ZAUM1581
AB C Y Z
0 1 2 9
-_
12
1. Self-diagnosis device
ZAUM15821
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Operation and important riding points
5-2
51000 km (600 mi) and beyond
The vehicle can now be operated nor-
mally.
NOTICE
ECA10311
Keep the engine speed out of
the tachometer red zone.
If any engine trouble should oc-
cur during the engine break-in
period, immediately have a
Yamaha dealer check the vehi-
cle.
EAU86690
Starting the engine
The ignition circuit cut-off system will
enable starting when:
the transmission is in the neutral
position or
the transmission is in gear, the
sidestand is up, and the clutch le-
ver is pulled.
To start the engine
1. Turn the main switch on and set
the engine stop switch to the run
position.
2. Confirm the indicator and warning
light(s) come on for a few sec-
onds, and the go off. (See page
3-2.)
TIP
Do not start the engine if the en-
gine trouble warning light remains
on.
The ABS warning light should
come on and stay on until the ve-
hicle reaches a speed of 10 km/h
(6 mi/h).
NOTICE
ECA24110
If a warning or indicator light does
not work as described above, have a
Yamaha dealer check the vehicle.
3. Shift the transmission into the
neutral position.
4. Start the engine by pushing the
start switch.
5. Release the start switch when the
engine starts, or after 5 seconds.
Wait 10 seconds before pressing
the switch again to allow battery
voltage to restore.
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Periodic maintenance and adjustment
6-6
6
EAU72750
TIP
The air filter needs more frequent service if you are riding in unusually wet or
dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cyl-
inders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
26Engine oil filter el-
ement• Replace.√√√√√
27*Cooling system• Check coolant level and vehicle
for coolant leakage.√√√√√
• Change. Every 3 years
28*Front and rear
brake switches• Check operation.√√√√√√
29*Moving parts and
cables• Lubricate.√√√√√
30*Throttle grip hous-
ing and cable• Check operation and free play.
• Adjust the throttle cable free
play if necessary.
• Lubricate the throttle grip hous-
ing and cable.√√√√√
31*Lights, signals and
switches• Check operation.
• Adjust headlight beam.√√√√√√ NO. ITEM
X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READING
ANNUAL CHECK
16121824
0.6 3.5 7 10.5 14
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Periodic maintenance and adjustment
6-7
6
EAU18782
Removing and installing cowl-
ings
The cowlings shown need to be re-
moved to perform some of the mainte-
nance jobs described in this chapter.
Refer to this section each time a cowl-
ing needs to be removed and installed.
EAU46742Cowling A
To remove the cowling
Remove the bolts, and then take the
cowling off.
To install the cowling
Place the cowling in the original posi-
tion, and then install the bolts.
EAU19623
Checking the spark plug
The spark plug is an important engine
component, which should be checked
periodically, preferably by a Yamaha
dealer. Since heat and deposits will
cause any spark plug to slowly erode,
it should be removed and checked in
accordance with the periodic mainte-
nance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
The porcelain insulator around the
center electrode of the spark plug
should be a medium-to-light tan (the
ideal color when the vehicle is ridden
normally). If the spark plug shows a
distinctly different color, the engine
could be operating improperly. Do not
attempt to diagnose such problems
yourself. Instead, have a Yamaha deal-
er check the vehicle.
If the spark plug shows signs of elec-
trode erosion and excessive carbon or
other deposits, it should be replaced.
Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
1. Cowling A
1. Bolt
ZAUM17381
1
Specified spark plug:
NGK/MR8E9
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Periodic maintenance and adjustment
6-8
6Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the spark
plug threads.
TIP
If a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4…
1/2 turn past finger tight. However, the
spark plug should be tightened to the
specified torque as soon as possible.
EAUM2584
Engine oil and oil filter ele-
ment
The engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil filter ele-
ment replaced at the intervals specified
in the periodic maintenance and lubri-
cation chart.
To check the engine oil level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion. A slight tilt to the side can
result in a false reading.
2. Start the engine, warm it up for
several minutes, and then turn it
off.
3. Wait a few minutes until the oil set-
tles, remove the oil filler cap, wipe
the dipstick clean, insert it back
into the oil filler hole (without
screwing it in), and then remove it
again to check the oil level.
NOTICE: Do not operate the ve-
hicle until you know that the en-
gine oil level is sufficient.
[ECA10012]
TIP
The engine oil should be between the
minimum and maximum level marks.
1. Spark plug gap
Spark plug gap:
0.8–0.9 mm (0.031–0.035 in)
Tightening torque:
Spark plug:
12.5 N·m (1.25 kgf·m, 9.22 lb·ft)
1
ZAUM0037
1. Engine oil filler cap
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Periodic maintenance and adjustment
6-11
6
EAU85450
Why Yamalube
YAMALUBE oil is a Genuine YAMAHA
Part born of the engineers’ passion
and belief that engine oil is an impor-
tant liquid engine component. We form
teams of specialists in the fields of me-
chanical engineering, chemistry, elec-
tronics and track testing, and have
them develop the engine together with
the oil it will use. Yamalube oils take full
advantage of the base oil’s qualities
and blend in the ideal balance of addi-
tives to make sure the final oil clears
our performance standards. Thus,
Yamalube mineral, semisynthetic and
synthetic oils have their own distinct
characters and value. Yamaha’s expe-
rience gained over many years of re-
search and development into oil since
the 1960’s helps make Yamalube the
best choice for your Yamaha engine.
EAU20071
Coolant
The coolant level should be checked
before each ride. In addition, the cool-
ant must be changed at the intervals
specified in the periodic maintenance
and lubrication chart.
EAUE4091To check the coolant level
1. Place the vehicle on a level sur-
face.
2. Remove cowling A. (See page
6-7.)
3. Hold the vehicle in an upright po-
sition.
TIP
The coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.
4. Check the coolant level in the
coolant reservoir.
TIP
The coolant should be between the
minimum and maximum level marks.
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10-1
10
Index
A
ABS ....................................................... 3-15
ABS warning light ................................... 3-3
Air filter element and check hose,
replacing and cleaning ....................... 6-13
B
Battery .................................................. 6-30
Brake and clutch levers, checking and
lubricating ........................................... 6-27
Brake and shift pedals, checking and
lubricating ........................................... 6-26
Brake fluid, changing ............................ 6-23
Brake fluid level, checking .................... 6-22
Brake lever ............................................ 3-14
Brake light switches.............................. 6-20
Brake pedal........................................... 3-14
Brake pedal free play, adjusting ........... 6-20
C
Cables, checking and lubricating ......... 6-25
Care ........................................................ 7-1
Catalytic converter ................................ 3-18
Clutch lever ........................................... 3-13
Clutch lever free play, adjusting ........... 6-18
Coolant ................................................. 6-11
Coolant temperature warning light ......... 3-2
Cowlings, removing and installing .......... 6-7
D
Data recording, vehicle ........................... 9-3
Diagnostic connectors ............................ 9-2
Dimmer switch ...................................... 3-12
Drive chain, cleaning and lubricating .... 6-25
Drive chain slack................................... 6-23
E
Engine break-in....................................... 5-1
Engine idling speed .............................. 6-13
Engine oil and oil filter element ............... 6-8
Engine overheating ............................... 6-37
Engine serial number .............................. 9-1
Engine trouble warning light ................... 3-3
F
Front and rear brake pads, checking.... 6-21
Front brake lever free play, checking ... 6-19
Front fork, checking .............................. 6-28
Fuel ....................................................... 3-16
Fuel consumption, tips for reducing ....... 5-5
Fuel tank cap ........................................ 3-16
Fuel tank overflow hose ........................ 3-18
Fuses, replacing.................................... 6-31
H
Handlebar switches .............................. 3-12Helmet holder ....................................... 3-20
High beam indicator light ....................... 3-2
Horn switch .......................................... 3-12
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system............... 3-21
Indicator lights and warning lights ......... 3-2
L
License plate light bulb, replacing........ 6-34
M
Main switch/steering lock....................... 3-1
Maintenance and lubrication, periodic ... 6-4
Maintenance, emission control
system.................................................. 6-3
Matte color, caution ............................... 7-1
Model label ............................................. 9-1
Multi-function meter unit ........................ 3-4
N
Neutral indicator light ............................. 3-2
P
Parking ................................................... 5-6
Part locations ......................................... 2-1
Pass switch .......................................... 3-12
S
Safety information .................................. 1-1
Seat ...................................................... 3-19
Shifting ................................................... 5-4
Shift light ................................................ 3-3
Shift pedal ............................................ 3-13
Sidestand ............................................. 3-20
Sidestand, checking and lubricating .... 6-27
Spark plug, checking ............................. 6-7
Specifications ......................................... 8-1
Start/Engine stop switch ...................... 3-12
Starting the engine ................................. 5-2
Steering, checking................................ 6-29
Storage ................................................... 7-4
Supporting the motorcycle................... 6-34
Swingarm pivots, lubricating ................ 6-28
T
Tail/brake light ...................................... 6-33
Throttle grip and cable, checking and
lubricating .......................................... 6-26
Throttle grip free play, adjusting........... 6-14
Tires ...................................................... 6-15
Tool kit.................................................... 6-2
Troubleshooting ................................... 6-35
Troubleshooting chart .......................... 6-36
Turn signal indicator light ....................... 3-2
Turn signal light bulb, replacing ........... 6-33
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