2019 YAMAHA XMAX 125 check engine light

Periodic maintenance an d a djustment
8-9
8
EAU19623
Checkin g the spark plugThe 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.
TIPIf 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.
Specifie
d spark plu g:
NGK/CPR8EA-9
1. Spark plug gap
Spark plu g g ap:
0.8–0.9 mm (0.031–0.035 in)
Ti ghtenin g torque:
Spark plug: 12.5 N·m (1.25 kgf·m, 9.22 lb·ft)
UB9YE0E0.book Page 9 Wednesday, January 6, 2021 3:03 PM

Periodic maintenance an d a djustment
8-10
8
EAU36113
CanisterThis model is equipped with a canister
to prevent the discharging of fuel vapor
into the atmosphere. Before operating
this vehicle, make sure to check the
following:
 Check each hose connection. 
Check each hose and canister for
cracks or damage. Replace if
damaged.
 Make sure that the canister
breather is not blocked, and if
necessary, clean it.
EAU66995
Engine oil an d oil strainerThe engine oil level should be checked
before each ride. In addition, the oil
must be changed and the oil strainer
cleaned at the intervals specified in the
periodic maintenance and lubrication
chart.
To check the en gine oil level
1. Place the vehicle 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 engine oil filler
cap, wipe the engine oil dipstick
clean, insert it back into the oil fill-
er hole (without screwing it in), and
then remove it again to check the
oil level. WARNING! The muffler
an d muffler protector become
very hot d uring use. To avoi d
possi ble burns, let the muffler
an d protector cool before re-
movin g the oil filler cap.
[EWA17810]
1. Canister
2. Canister breather hoseZAUM1942
2 2
1
22
1
2
ZAUM1458
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Periodic maintenance an d a djustment
8-14
8
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.TIPThe coolant should be between the mi-
nimum and maximum level marks.
3. If the coolant is at or below the mi-nimum level mark, have a Yamaha
dealer add coolant to the reser-
voir.
EAU33032
Chan gin g the coolant
The coolant must be changed at the in-
tervals specified in the periodic main-
tenance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove the ra diator cap when the en gine is
hot.
[EWA10382] EAU67174
Air filter an
d V- belt case air fil-
ter elementsThe air filter element should be re-
placed and the V-belt case air filter el-
ement should be cleaned at the
intervals specified in the periodic main-
tenance and lubrication chart. Service
the air filter elements more frequently if
you are riding in unusually wet or dusty
areas. The air filter check hose and V-
belt case air filter check hose must be
frequently checked and cleaned if nec-
essary.
Cleanin g the air filter check hose
1. Coolant level check window
2. Maximum level mark
3. Minimum level markZAUM1947
1 2
2
3 2
3
Coolant reservoir capacity (up to
the maximum level mark): 0.13 L (0.14 US qt, 0.11 Imp.qt)
1. Air filter check hoseZAUM1948
1 11
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12-1
12
Index
AABS warning light ................................... 5-2
Acceleration and deceleration ................ 7-3
Activating the Stop and Start System .... 4-1
Air filter and V-belt case air filter
elements ............................................. 8-14
Anti-lock brake system (ABS)............... 5-14
Auxiliary DC jack .................................. 5-26BBattery .................................................. 8-26
Brake fluid, changing............................ 8-22
Brake fluid level, checking.................... 8-21
Brake lever, front .................................. 5-14
Brake lever, rear ................................... 5-14
Brake levers, lubricating ....................... 8-23
Braking ................................................... 7-3CCables, checking and lubricating ......... 8-23
Canister ................................................ 8-10
Care ........................................................ 9-1
Catalytic converter ............................... 5-20
Centerstand and sidestand, checking and lubricating ................................... 8-24
Coolant ................................................. 8-13DData recording, vehicle......................... 11-2
Diagnostic connector ........................... 11-2
Dimmer/Pass switch............................. 5-12EEmergency mode ................................. 8-34
Engine break-in ...................................... 7-1
Engine oil and oil strainer ..................... 8-10
Engine overheating ............................... 8-33
Engine serial number ............................ 11-1
FFinal transmission oil............................ 8-12
Front and rear brake lever free play, checking ............................................ 8-19
Front and rear brake pads, checking ... 8-20
Front fork, checking ............................. 8-25
Front turn signal light ........................... 8-29
Fuel ...................................................... 5-18
Fuel consumption, tips for reducing ...... 7-4
Fuel tank cap........................................ 5-17
Fuel tank overflow hose ....................... 5-20
Fuses, replacing ................................... 8-27HHandlebar position, adjusting .............. 5-25
Handlebar switches ............................. 5-12
Hazard switch ...................................... 5-13
High beam indicator light ....................... 5-1
Horn switch .......................................... 5-13IIdentification numbers ......................... 11-1
Ignition circuit cut-off system .............. 5-27
Indicator lights and warning lights ......... 5-1KKey, handling of smart and mechanical keys...................................................... 3-3LLicense plate light bulb, replacing ....... 8-30MMain switch ............................................ 3-8
Maintenance and lubrication, periodic... 8-4
Maintenance, emission control system ................................................. 8-3
Malfunction indicator light (MIL)............. 5-1
Matte color, caution ............................... 9-1 Model label ........................................... 11-1
Multi-function display ............................. 5-4
OOperating range of the smart key
system .................................................. 3-2PPanel, removing and installing ................ 8-8
Parking.................................................... 7-4
Part locations.......................................... 2-1
Precautions when using the Stop and Start System ......................................... 4-3SSafe-riding points ................................... 1-5
Safety information................................... 1-1
Shock absorber assemblies, adjusting ............................................. 5-25
Sidestand.............................................. 5-27
Smart key................................................ 3-5
Smart key battery, replacing................... 3-6
Smart key system ................................... 3-1
Smart key system indicator light ............ 5-2
Smart key system, troubleshooting ...... 8-31
Spark plug, checking .............................. 8-9
Specifications ....................................... 10-1
Speedometer .......................................... 5-3
Starting off .............................................. 7-3
Starting the engine ................................. 7-2
Steering, checking ................................ 8-25
Stop and Start System ........................... 4-1
Stop and Start System indicator light..... 5-2
Stop and Start System operation ........... 4-1
Stop and Start System switch .............. 5-13
Stop/Run/Start switch .......................... 5-13
Storage ................................................... 9-3
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