check engine light YAMAHA MT-125 2017 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 .....................................3-14
Brake lever ....................................3-14
Brake pedal ...................................3-15
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-17
Catalytic converter ........................3-18
Rider seat ......................................3-19
Sidestand ......................................3-20
Ignition circuit cut-off system........3-20
For your safety – pre-operation
checks...............................................4-1
Operation and important riding
points.................................................5-1
Starting the engine ..........................5-2
Shifting ............................................5-3
Tips for reducing fuel
consumption ................................5-4
Engine break-in ...............................5-4
Parking ............................................5-5
Periodic maintenance and
adjustment........................................6-1
Owner’s tool kit ...............................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4
Removing and installing cowlings ...6-7
Checking the spark plug .................6-8Engine oil and oil filter element ....... 6-9
Coolant ......................................... 6-12
Replacing the air filter element
and cleaning the check hose..... 6-14
Checking the engine idling
speed......................................... 6-14
Adjusting the throttle grip free
play ............................................ 6-15
Valve clearance ............................. 6-16
Tires .............................................. 6-16
Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the front brake lever
free play ..................................... 6-20
Adjusting the brake pedal free
play ............................................ 6-21
Brake light switches ...................... 6-21
Checking the front and rear brake
pads........................................... 6-22
Checking the brake fluid level....... 6-23
Changing the brake fluid............... 6-24
Drive chain slack ........................... 6-24
Cleaning and lubricating the drive
chain .......................................... 6-26
Checking and lubricating the
cables ........................................ 6-26
Checking and lubricating the
throttle grip and cable ............... 6-27
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
brake pedal................................ 6-28
Checking and lubricating the
sidestand ................................... 6-28
Lubricating the swingarm
pivots ......................................... 6-29
Checking the front fork ................. 6-29
Checking the steering ................... 6-30
Checking the wheel bearings ....... 6-30
Battery .......................................... 6-31
Replacing the fuses ...................... 6-32
Replacing the headlight bulb ........ 6-33
Auxiliary lights ............................... 6-35
Tail/brake light .............................. 6-35
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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. Refer to page
6-16 for tire specifications and more in-
formation on 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.
Point the front wheel straight
ahead on the trailer or in the truck
bed, and choke it in a rail to pre-
vent movement.
Shift the transmission in gear (for
models with a manual transmis-
sion).
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-mounted
handlebars 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 The electrical circuit of the warning
light can be checked according to the
following procedure.
1. Turn the key to “ON”.
2. If the warning light does not come
on, have a Yamaha dealer check
the electrical circuit.
EAU11486Engine trouble warning light “ ”
This warning light comes on if a prob-
lem is detected in the electrical circuit
monitoring the engine. If this occurs,
have a Yamaha dealer check the vehi-
cle.
The electrical circuit of the warning
light can be checked by turning the key
to “ON”. The warning light should
come on for a few seconds, and then
go off.
If the warning light does not come on
initially when the key is turned to “ON”,
or if the warning light remains on, have
a Yamaha dealer check the electrical
circuit.
EAU69890ABS warning light “ ”
In normal operation, the ABS warning
light comes on when the key is turned
to “ON”, and goes off after traveling at
a speed of 10 km/h (6 mi/h) or higher.
If the ABS warning light:
does not come on when the key is
turned to “ON”
comes on or flashes while riding
does not go off after traveling at a
speed of 10 km/h (6 mi/h) or high-
erThe ABS may not work correctly. If any
of the above occurs, have a Yamaha
dealer check the system as soon as
possible. (See page 3-15 for an expla-
nation of the ABS.)
WARNING
EWA16041
If the ABS warning light does not go
off after traveling at a speed of 10
km/h (6 mi/h) or higher, or if the
warning light comes on or flashes
while riding, the brake system re-
verts to conventional braking. If ei-
ther of the above occurs, or if the
warning light does not come on at
all, use extra caution to avoid possi-
ble wheel lock during emergency
braking. Have a Yamaha dealer
check the brake system and electri-
cal circuits as soon as possible.
EAUM3440Tachometer high-rpm warning light
This light flashes at 9500 r/min to warn
you that the engine speed is about to
enter the high-rpm zone. Once the en-
gine speed reaches 10000 r/min, this
light will come on to warn you that it is
necessary to shift up to avoid engine
damage.
To activate or deactivate the tachome-
ter high-rpm warning light, hold the
“INFO” button pushed, turn the key to
“ON”, and when the tachometer high-
rpm warning light starts flashing, press
the “SELECT” button.
TIP
When activating or deactivating the
warning light the function, after press-

ABS
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Instrument and control functions
3-6
32. Push the “SELECT” button for two
seconds, and the hour digits will
start flashing.
3. Use the “RESET” button to set the
hours.
4. Push the “SELECT” button, and
the minute digits will start flashing.
5. Use the “RESET” button to set the
minutes.
6. Push the “SELECT” button to con-
firm settings and start the clock.
TIP
When setting the hours and minutes, a

creases the increment value one by
one. You may also push and hold the
button to increase the value continu-
ously.
Fuel meter
The fuel meter indicates the amount of
fuel in the fuel tank. The display seg-
ments of the fuel meter disappear from
“F” (full) towards “E” (empty) as the fuel
level decreases. When the fuel level
becomes low, the last segment will
flash and the fuel level warninglight “ ” will come on (“LOW FUEL”
message will also appear). Refuel as
soon as possible.
TIP
If a problem is detected in the fuel me-
ter electrical circuit, all display seg-
ments of the fuel meter will flash eight
times, then go off for 3 seconds, re-
peatedly. If this occurs, have your
Yamaha dealer check the vehicle.
Coolant temperature meter
The coolant temperature meter indi-
cates the temperature of the coolant,
and therefore the engine. When the
coolant temperature is at its upper lim-
it, the second segment from the top
will start to flash. Should this occur, re-
duce the load on the engine by riding at
a moderate pace, at low rpm, until the
coolant temperature goes down. If the
top two segments and “ ” start flash-
ing (“HIGH TEMP” message will also
appear), stop the vehicle and let the
engine cool.
1. Fuel meter
2. Fuel level warning light “ ”
3. Fuel reserve tripmeter
4. Information display
Lo
Hi
1/2
x1000r/min
ZAUM1303
km/h
FTRIP
21
34
1. Coolant temperature warning indicator Ž
2. Information display
3. Coolant temperature meter
Lo
Hi
ZAUM1304
31
2
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Operation and important riding points
5-2
5
EAUM3531
Starting the engine
In order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
The transmission is in the neutral
position.
The transmission is in gear with
the clutch lever pulled and the
sidestand up.
See page 3-20 for more informa-
tion.
1. Turn the key to “ON” and make
sure that the engine stop switch is
set to “ ”.
The following warning lights and
indicator lights should come on for
a few seconds, then go off.
Neutral indicator light
Turn signal indicator light
High beam indicator light
Engine trouble warning light
Fuel level warning light
Tachometer high-rpm warn-
ing light
NOTICE
ECA11834
If a warning or indicator light does
not come on initially when the key is
turned to “ON”, or if a warning or in-
dicator light remains on, see page
3-2 for the corresponding warning
and indicator light circuit check.
The ABS warning light should
come on when the key is turned to
“ON”, and then go off after travel-
ing at a speed of 10 km/h (6 mi/h)
or higher.
NOTICE
ECA17682
If the ABS warning light does not
come on and then go off as ex-
plained above, see page 3-2 for the
warning light circuit check.
2. Shift the transmission into the
neutral position. The neutral indi-
cator light should come on. If not,
ask a Yamaha dealer to check the
electrical circuit.
3. Start the engine by pushing the
start switch.
If the engine fails to start, release
the start switch, wait a few sec-
onds, and then try again. Each
starting attempt should be as
short as possible to preserve the
battery. Do not crank the engine
more than 10 seconds on any one
attempt.
NOTICE
ECA11043
For maximum engine life, never ac-
celerate hard when the engine is
cold!
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Periodic maintenance and adjustment
6-6
6
EAU72740
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 change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
25 Engine oil• Change (warm engine before
draining).At the initial interval and when
the oil change indicator flashes
or comes on
• Check oil level and vehicle for oil
leakage.Every 3000 km (1800 mi)
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
6-8
6
EAU19607
Checking the spark plug
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic main-
tenance and lubrication chart. In addi-
tion, the condition of the spark plug
can reveal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.To check the spark plug
1. Check that the porcelain insulator
around the center electrode of the
spark plug is a medium-to-light
tan (the ideal color when the vehi-
cle is ridden normally).
TIP
If the spark plug shows a distinctly dif-
ferent color, the engine could be oper-
ating improperly. Do not attempt to
diagnose such problems yourself. In-
stead, have a Yamaha dealer check
the vehicle.
2. Check the spark plug for electrode
erosion and excessive carbon or
other deposits, and replace it if
necessary.
3. Measure the spark plug gap with a
wire thickness gauge and, if nec-
essary, adjust the gap to specifi-
cation.
1. Spark plug cap
1. Spark plug wrench
Specified spark plug:
NGK/CR9E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
1
ZAUM0037
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Periodic maintenance and adjustment
6-9
6 To install the spark plug
1. Clean the surface of the spark
plug gasket and its mating sur-
face, and then wipe off any grime
from the spark plug threads.
2. Install the spark plug with the
spark plug wrench, and then tight-
en it to the specified torque.
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.
3. Install the spark plug cap.
EAUM3491
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.
Tightening torque:
Spark plug:
12.5 N·m (1.25 kgf·m, 9.04 lb·ft)
1. Engine oil filler cap
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Periodic maintenance and adjustment
6-12
613. Turn the engine off, and then
check the oil level and correct it if
necessary.
14. Reset the oil change indicator.
(See page 3-10.)
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.
EAUM1726To check the coolant level
1. Place the vehicle on a level sur-
face and hold it in an upright posi-
tion.
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.
2. Check the coolant level in the
coolant reservoir.
TIP
The coolant should be between the
minimum and maximum level marks.
1. Coolant reservoir cap
2. Maximum level mark
3. Minimum level mark
ZAUM1207
FULL
LOW2
3
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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 ....................... 6-14
Auxiliary lights ....................................... 6-35
B
Battery .................................................. 6-31
Brake and clutch levers, checking and
lubricating ........................................... 6-27
Brake fluid, changing ............................ 6-24
Brake fluid level, checking .................... 6-23
Brake lever ............................................ 3-14
Brake light switches.............................. 6-21
Brake pedal........................................... 3-15
Brake pedal, checking and
lubricating ........................................... 6-28
Brake pedal free play, adjusting ........... 6-21
C
Cables, checking and lubricating ......... 6-26
Care ........................................................ 7-1
Catalytic converter ................................ 3-18
Clutch lever ........................................... 3-13
Clutch lever free play, adjusting ........... 6-19
Coolant ................................................. 6-12
Cowlings, removing and installing .......... 6-7
D
Data recording, vehicle ........................... 9-2
Diagnostic connectors ............................ 9-2
Dimmer switch ...................................... 3-12
Drive chain, cleaning and lubricating .... 6-26
Drive chain slack................................... 6-24
E
Engine break-in....................................... 5-4
Engine idling speed, checking .............. 6-14
Engine oil and oil filter element ............... 6-9
Engine stop switch ............................... 3-12
Engine trouble warning light ................... 3-3
F
Front and rear brake pads, checking.... 6-22
Front brake lever free play, checking ... 6-20
Front fork, checking .............................. 6-29
Fuel ....................................................... 3-17
Fuel consumption, tips for reducing ....... 5-4
Fuel level warning light ........................... 3-2
Fuel tank cap ........................................ 3-16
Fuses, replacing.................................... 6-32
H
Handlebar switches .............................. 3-12
Headlight bulb, replacing ...................... 6-33High beam indicator light ....................... 3-2
Horn switch .......................................... 3-12
I
Identification numbers ............................ 9-1
Ignition circuit cut-off system............... 3-20
Indicator lights and warning lights ......... 3-2
Info switch ............................................ 3-12
L
License plate light bulb, replacing........ 6-36
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 ................................................... 5-5
Part locations ......................................... 2-1
Pass switch .......................................... 3-12
R
Rider seat ............................................. 3-19
S
Safety information .................................. 1-1
Shifting ................................................... 5-3
Shift pedal ............................................ 3-14
Sidestand ............................................. 3-20
Sidestand, checking and lubricating .... 6-28
Spark plug, checking ............................. 6-8
Specifications ......................................... 8-1
Starting the engine ................................. 5-2
Start switch .......................................... 3-12
Steering, checking................................ 6-30
Storage ................................................... 7-4
Supporting the motorcycle................... 6-37
Swingarm pivots, lubricating ................ 6-29
T
Tail/brake light ...................................... 6-35
Throttle grip and cable, checking and
lubricating .......................................... 6-27
Throttle grip free play, adjusting........... 6-15
Tires ...................................................... 6-16
Tool kit.................................................... 6-2
Troubleshooting ................................... 6-37
Troubleshooting charts ........................ 6-38
Turn signal indicator light ....................... 3-2
Turn signal light bulb, replacing ........... 6-36
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