2021 YAMAHA NMAX 155 check engine light

Periodic maintenance an d a djustment
9-9
9 2. Install the windshield by installing
the screws.
EAU67161
Checkin g the spark plu gThe 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 plu g
1. Place the vehicle on the center- stand.
2. Remove panels A and B. (See page 9-7.)
3. Remove the spark plug cap. 4. Remove the spark plug as shown,
with the spark plug wrench includ-
ed in the owner’s tool kit.
To check the spark plu g
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).
TIPIf 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.
1. Spark plug cap
1
1. Spark plug wrench
1
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Periodic maintenance an d a djustment
9-11
9
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]
TIPThe engine oil should be between the
tip of the dipstick and the maximum
level mark.4. If the engine oil is not between the
tip of the dipstick and the maxi-
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.
1. Canister
2. Canister breather
2
1
1. Oil filler hole
2. O-ring
3. Engine oil dipstick
4. Maximum level mark
5. Tip of the engine oil dipstick
3245
1
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Periodic maintenance an d a djustment
9-15
9
EAU20071
CoolantThe 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.
EAUN2930
To 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 in the
coolant reservoir.TIPThe coolant should be between the
minimum and maximum level marks.
3. If the coolant is at or below theminimum level mark, remove the
right floorboard mat by pulling it
up.
4. Remove the coolant reservoir cov- er. 5. Remove the coolant reservoir cap,
add coolant to the maximum level
mark, and then install the reservoir
cap. WARNING! Remove only
the coolant reservoir cap. Never
attempt to remove the ra diator
cap when the en gine is hot.
[EWA15162]
NOTICE: If coolant is not
availa ble, use d istilled water or
soft tap water instea d. Do not
use har d water or salt water
since it is harmful to the en gine.
If water has been used instead
of coolant, replace it with cool-
ant as soon as possi ble, other-
wise the coolin g system will not
b e protecte d a gainst frost an d
corrosion. If water has been
1. Maximum level mark
2. Minimum level mark
1. Floorboard mat
1
2
1
1. Coolant reservoir cover
1
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Periodic maintenance an d a djustment
9-34
9
If the smart key system does not work
after checking the above items, have a
Yamaha dealer check the smart key system.
TIPSee Emergency mode on page 9-38
for information on starting the engine
without the smart key.
EAU76843
Stop an d Start System trou ble-
shootin g
If a problem occurs, check the follow-
ing before taking the vehicle to a
Yamaha dealer.
The Stop an d Start System in dicator
lig ht does not come on.
1. Is the main switch turned on?
2. Is the Stop and Start System switch set to “ ”?
3. Was the engine warmed up suffi- ciently after starting?
4. After the engine was warmed up, was the engine left idling for a cer-
tain period of time?
5. Did the vehicle travel at a speed of 10 km/h or higher? Even if the preceding conditions are
met, the Stop and Start System may
not activate in order to preserve bat-
tery power. In this case, continue to
drive the vehicle.
In addition, the Stop and Start System
indicator light does not come on if the
engine trouble warning light is on.
If the Stop and Start System indicator
light still does not come on after you
checked the preceding conditions,
have a Yamaha dealer check the vehi-
cle as soon as possible.
The Stop an
d Start System in dicator
li g ht comes on, b ut the engine does
not stop automatically. 1. Was the vehicle stopped com- pletely?
The engine may not stop automat-
ically until the vehicle is stopped
for a certain period of time. Try
bringing the vehicle to a complete
stop.
2. Is the throttle grip turned? The engine does not stop auto-
matically if the throttle grip is not in
the fully closed position. Turn the throttle grip to the fully
closed position.
If the engine still does not stop auto-
matically after you checked the pre-
ceding conditions, have a Yamaha
dealer check the vehicle as soon as
possible.
After the eng ine was stopped b y the
Stop an d Start System, the en gine
d oes not restart even if the throttle
g rip is turne d.
1. Is the Stop and Start System switch set to “ ”?
If the Stop and Start System
switch is set to “ ” while the Stop
and Start System is activated, the
Stop and Start System will be
turned off.
2. Was the sidestand operated? When the sidestand is lowered,
the Stop and Start System is de-
activated.
3. Was the engine left stopped by the Stop and Start System for a
long period of time?
A
AA
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13-1
13
IndexAABS ....................................................... 6-12
ABS warning light ................................... 6-2
Acceleration and deceleration ................ 8-3
Activating the Stop and Start System .... 4-1
Air filter and V-belt case air filter
elements ............................................. 9-16
App Connect icon ................................... 6-4BBattery .................................................. 9-28
Brake fluid, changing ............................ 9-24
Brake fluid level, checking .................... 9-23
Brake lever, front .................................. 6-11
Brake lever, rear.................................... 6-11
Brake levers, lubricating ....................... 9-25
Braking.................................................... 8-3CCables, checking and lubricating ......... 9-25
Canister................................................. 9-11
Care ...................................................... 10-1
Catalytic converter ................................ 6-17
CCU (Communication Control Unit) ....... 5-1
Centerstand and sidestand, checking and lubricating .................... 9-26
Clock....................................................... 6-5
Coolant ................................................. 9-15
Coolant temperature meter .................... 6-5DData recording, vehicle ......................... 12-2
Diagnostic connector............................ 12-2
Dimmer switch ...................................... 6-10
Display units, switching .......................... 6-4EEmergency mode.................................. 9-38 Engine break-in ...................................... 8-1
Engine oil and oil strainer ..................... 9-11
Engine overheating ............................... 9-37
Engine serial number ............................ 12-1
FFinal transmission oil ............................ 9-13
Front and rear brake lever free play,
checking............................................. 9-21
Front and rear brake pads, checking ... 9-22
Front fork, checking ............................. 9-27
Fuel ....................................................... 6-15
Fuel consumption, tips for reducing ...... 8-3
Fuel meter .............................................. 6-4
Fuel tank cap ........................................ 6-14
Fuel tank overflow hose ....................... 6-17
Fuses, replacing ................................... 9-29HHandlebar switches .............................. 6-10
Hazard switch....................................... 6-10
Helmet holders ..................................... 6-18
High beam indicator light ....................... 6-1
Horn switch .......................................... 6-10IIdentification numbers .......................... 12-1
Ignition circuit cut-off system ............... 6-22
Incoming call indicator light ................... 6-3
Incoming notification indicator light ....... 6-3
Indicator lights and warning lights ......... 6-1KKey, handling of smart and mechanical keys................................... 3-3MMain switch ............................................ 3-7
Maintenance and lubrication, periodic ... 9-3 Maintenance,
emission control system .......................9-2
Malfunction indicator light (MIL)..............6-1
Matte color, caution ..............................10-1
Menu switch..........................................6-11
Model label ...........................................12-1
Multi-function display .............................6-6
Multi-function meter unit .........................6-3
OOperating range of the smart key system ..................................................3-2PPanels, removing and installing ..............9-7
Parking ....................................................8-4
Part locations ..........................................2-1
Power outlet ..........................................6-21
Precautions when using the Stop and Start System .........................4-3SSafe-riding points....................................1-5
Safety information ...................................1-1
Seat .......................................................6-17
Shock absorber assemblies,
adjusting .............................................6-20
Sidestand ..............................................6-22
Smart key ................................................3-4
Smart key battery, replacing ...................3-6
Smart key system ...................................3-1
Smart key system indicator light.............6-2
Smart key system, troubleshooting ......9-33
Smartphone battery level meter..............6-4
Spark plug, checking ..............................9-9
Special features ......................................5-1
Specifications .......................................11-1
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Index
13-2
13
Speedometer .......................................... 6-4
Starting off .............................................. 8-2
Starting the engine ................................. 8-2
Start switch........................................... 6-10
Steering, checking ................................ 9-27
Stop and Start System ........................... 4-1
Stop and Start System indicator light .... 6-2
Stop and Start System operation ........... 4-1
Stop and Start System switch .............. 6-11
Stop and Start System
troubleshooting .................................. 9-34
Storage ................................................. 10-3
Storage compartments......................... 6-19TThrottle grip and cable, checking and lubricating .................... 9-25
Throttle grip free play, checking ........... 9-19
Tires ...................................................... 9-19
Tool kit .................................................... 9-1
Traction control system ........................ 6-13
Traction control system indicator light ... 6-2
Troubleshooting.................................... 9-33
Troubleshooting chart .......................... 9-36
Turn signal indicator lights ..................... 6-1
Turn signal light bulb (front), replacing............................................. 9-31
Turn signal light bulb (rear), replacing............................................. 9-32
Turn signal switch................................. 6-10VValve clearance .................................... 9-19
V-belt, checking.................................... 9-24
Vehicle identification number ............... 12-1
Vehicle lights ........................................ 9-31 VVA indicator.......................................... 6-5
WWheel bearings, checking .................... 9-28
Wheels ................................................. 9-21YYamalube ............................................. 9-13
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