2018 YAMAHA XMAX 125 check engine light

Periodic maintenance and adjustment
7-8
7
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.Clean 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.
Specified spark plug:
NGK/CR9E
1. Spark plug gap
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
Tightening torque:
Spark plug:
12.5 N·m (1.25 kgf·m, 9.22 lb·ft)
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Periodic maintenance and adjustment
7-9
7
EAUM3332
Engine oil
The engine oil level should be checked
before each ride. In addition, the oil
must be changed at the intervals spec-
ified in the periodic maintenance and
lubrication chart and when the service
indicator light comes on.
To check the engine oil level
1. Place the scooter on the center-
stand. 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.
TIP
The engine oil should be between the
minimum and maximum level marks.
4. If the engine oil is below the mini-
mum level mark, add sufficient oil
of the recommended type to raise
it to the correct level.5. Insert the dipstick into the oil filler
hole, and then tighten the oil filler
cap.
To change the engine oil (with or
without oil filter element replace-
ment)
1. Start the engine, warm it up for
several minutes, and then turn it
off.
2. Place an oil pan under the engine
to collect the used oil.
3. Remove the engine oil filler cap
and the engine oil drain bolt to
drain the oil from the crankcase.
4. Check the drain bolt washer for
damage and replace it if neces-
sary.
1. Engine oil filler cap
2. Maximum level mark
3. Minimum level mark
1
3
2
1
ZAUM0685
1. Engine oil drain bolt
1. Engine oil drain bolt
2. Gasket
ZAUM11191
1
2
ZAUM0129
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Periodic maintenance and adjustment
7-12
7 6. Install the final transmission oil
drain bolt and its new gasket, and
then tighten the bolt to the speci-
fied torque.
7. Refill with the specified amount of
the recommended final transmis-
sion oil. WARNING! Make sure
that no foreign material enters
the final transmission case.
Make sure that no oil gets on
the tire or wheel.
[EWA11312]
8. Install the final transmission oil fill-
er cap and its new O-ring, and
then tighten the oil filler cap.
9. Check the final transmission case
for oil leakage. If oil is leaking,
check for the cause.
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.
EAU78580To check the coolant level
1. Place the vehicle on the center-
stand.
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 through
the check window.
TIP
The coolant should be between the
minimum and maximum level marks.
1. Final transmission oil drain bolt
Tightening torque:
Final transmission oil drain bolt:
20 N·m (2.0 kgf·m, 15 lb·ft)
Recommended final transmission
oil:
See page 9-1.
Oil quantity:
0.21 L (0.22 US qt, 0.18 Imp.qt)
ZAUM07031
1. Coolant level check window
2. Maximum level mark
3. Minimum level mark
1
2
3
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Periodic maintenance and adjustment
7-32
7
EAU60701
Troubleshooting
Although Yamaha vehicles 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 vehicle re-
quire any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the vehicle prop-
erly.
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.
EAU76551Smart key system troubleshooting
Please check the following items when
the smart key system does not work.
Is the smart key turned on? (See
page 3-5.)
Is the smart key battery dis-
charged? (See page 3-6.)Is the smart key battery installed
correctly? (See page 3-6.)
Is the smart key being used in a lo-
cation with strong radio waves or
other electromagnetic noise? (See
page 3-1.)
Are you using the smart key that is
registered to the vehicle?
Is the vehicle battery discharged?
When the vehicle battery is dis-
charged, the smart key system will
not operate. Please have the vehi-
cle battery charged or replaced.
(See page 7-26.)
If the smart key system does not work
after checking the above items, have a
Yamaha dealer check the smart key
system.
TIP
See Emergency mode on page 7-35
for information on starting the engine
without the smart key.
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11-1
11
Index
A
ABS ....................................................... 4-14
ABS warning light ................................... 4-1
Acceleration and deceleration ................ 6-3
Air filter and V-belt case air filter
elements ............................................. 7-14
Auxiliary DC jack ................................... 4-29
Auxiliary lights ....................................... 7-29
B
Battery .................................................. 7-26
Brake fluid, changing ............................ 7-21
Brake fluid level, checking .................... 7-20
Brake lever, front .................................. 4-13
Brake lever, rear.................................... 4-14
Brake levers, lubricating ....................... 7-23
Brake/tail light ....................................... 7-30
Braking.................................................... 6-4
C
Cables, checking and lubricating ......... 7-22
Care ........................................................ 8-1
Catalytic converters .............................. 4-20
Centerstand and sidestand, checking
and lubricating .................................... 7-24
Coolant ................................................. 7-12
D
Data recording, vehicle ......................... 10-2
Diagnostic connectors .......................... 10-2
Dimmer/Pass switch ............................. 4-12
E
Emergency mode.................................. 7-35
Engine break-in....................................... 6-5
Engine oil ................................................ 7-9
Engine serial number ............................ 10-1
Engine trouble warning light ................... 4-1
F
Final transmission oil ............................ 7-11
Front and rear brake lever free play,
checking ............................................. 7-19
Front and rear brake pads, checking.... 7-20
Front fork, checking .............................. 7-24
Front turn signal light ............................ 7-30
Fuel ....................................................... 4-18
Fuel consumption, tips for reducing ....... 6-5
Fuel tank cap ........................................ 4-17
Fuel tank overflow hose ........................ 4-19
Fuses, replacing.................................... 7-27
H
Handlebar position, adjusting ............... 4-25
Handlebar switches .............................. 4-12
Hazard switch ....................................... 4-12Headlights ............................................ 7-29
High beam indicator light ....................... 4-1
Horn switch .......................................... 4-12
I
Identification numbers .......................... 10-1
Ignition circuit cut-off system............... 4-27
Indicator lights and warning lights ......... 4-1
K
Key, handling of smart and mechanical
keys ...................................................... 3-3
L
License plate light bulb, replacing........ 7-31
M
Main switch ............................................ 3-8
Maintenance and lubrication, periodic ... 7-4
Maintenance, emission control
system.................................................. 7-3
Matte color, caution ............................... 8-1
Model label ........................................... 10-1
Multi-function display ............................. 4-3
O
Operating range of the smart key
system.................................................. 3-2
P
Panel, removing and installing ............... 7-7
Parking ................................................... 6-6
Part locations ......................................... 2-1
S
Safe-riding points ................................... 1-5
Safety information .................................. 1-1
Shock absorber assemblies,
adjusting............................................. 4-25
Sidestand ............................................. 4-26
Smart key ............................................... 3-5
Smart key battery, replacing .................. 3-6
Smart key system ................................... 3-1
Smart key system indicator light ............ 4-2
Smart key system, troubleshooting...... 7-32
Spark plug, checking ............................. 7-8
Specifications ......................................... 9-1
Speedometer .......................................... 4-2
Starting off.............................................. 6-3
Starting the engine ................................. 6-2
Steering, checking................................ 7-25
Stop/Run/Start switch .......................... 4-12
Storage ................................................... 8-4
Storage compartments ........................ 4-20
T
Tachometer ............................................ 4-3
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