YAMAHA NMAX 155 2021 Owners Manual

Periodic maintenance an d a djustment
9-28
9
EAU23292
Checkin g the wheel bearin gsThe front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
EAU50292
BatteryThe battery is located under the seat.
(See page 6-17.)
This model is equipped with a VRLA
(Valve Regulated Lead Acid) battery.
There is no need to check the electro-
lyte or to add distilled water. However,
the battery lead connections need to
be checked and, if necessary, tight-
ened.
WARNING
EWA10761
 Electrolyte is poisonous an d
d an gerous since it contains sul-
furic aci d, which causes severe b
urns. Avoi d any contact with
skin, eyes or clothin g an d al-
ways shiel d your eyes when
workin g near b atteries. In case
of contact, ad minister the fol-
lowin g FIRST AID.
EXTERNAL: Flush with plenty of water.
INTERNAL: Drink lar ge quan-
tities of water or milk an d im-
me diately call a physician.
EYES: Flush with water for 15 minutes an d seek prompt
me dical attention.
 Batteries pro duce explosive hy-
d ro gen gas. Therefore, keep
sparks, flames, ci garettes, etc.,
away from the battery an d pro-
vi de sufficient ventilation when
char gin g it in an enclose d
space.
 KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
To char ge the b attery
Have a Yamaha dealer charge the bat-
tery as soon as possible if it seems to
have discharged. Keep in mind that the
1. Positive battery lead (red)
2. Battery
3. Negative battery lead (black)
3
2
1
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Periodic maintenance an d a djustment
9-29
9 battery tends to discharge more quick-
ly if the vehicle is equipped with op-
tional electrical accessories.
NOTICE
ECA16522
To char
ge a VRLA (Valve Re gulate d
Lea d Aci d) battery, a special (con-
stant-volta ge) battery char ger is re-
quired . Using a conventional b attery
char ger will damag e the b attery.To store the b attery
1. If the vehicle will not be used for more than one month, remove the
battery, fully charge it, and then
place it in a cool, dry place.
NOTICE: When removin g the
b attery, be sure to turn the main
switch off, then disconnect the
ne gative lead before discon-
nectin g the positive lea d.
[ECA16304]
2. If the battery will be stored for
more than two months, check it at
least once a month and fully
charge it if necessary.
3. Fully charge the battery before in- stallation. NOTICE: When install-
in g the b attery, be sure to turn
the main switch off, then con- nect the positive lead
before
connectin g the ne gative lea d.
[ECA16842]
4. After installation, make sure that
the battery leads are properly con-
nected to the battery terminals.NOTICE
ECA16531
Always keep the b attery charged .
Storin g a d ischar ged battery can
cause permanent battery damag e.
EAUN2581
Replacin g the fusesThe fuse boxes, which contain the fus-
es for the individual circuits, are locat-
ed under panel C. (See page 9-7.)1. Fuse box
1
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Periodic maintenance an d a djustment
9-30
9
If a fuse is blown, replace it as follows. 1. Turn off the electrical circuit in question, and then turn off the
main switch.
2. Remove the panel C. (See page 9-7.) 3. Remove the blown fuse, and then
install a new fuse of the specified
amperage. WARNING! Do not
use a fuse of a hi gher ampera ge
ratin g than recommen ded to
avoi d causin g extensive dam-
a g e to the electrical system an d
possi bly a fire.
[EWA15132]
4. Turn the main switch on, and then
turn on the electrical circuit in
question to check if the device op-
erates.TIPIf the fuse immediately blows again,
have a Yamaha dealer check the elec-
trical system.5. Install the panel C. (See page 9-7.)
1. Signaling system fuse
2. Terminal fuse 1
3. Smart key system fuse
4. ABS motor fuse
5. ABS solenoid fuse
6. Spare fuse
7. Fuel injection system fuse
8. Backup fuse
9. Main fuse
10.Ignition fuse
11.Headlight fuse
12.ABS control unit fuse1
6
2
3
4
5
7
8
9
11
12
610
Specified
fuses:
Main fuse: 30.0 A
Terminal fuse 1:
5.0 A
Headlight fuse: 7.5 A
Signaling system fuse: 7.5 A
Ignition fuse:
7.5 A
Smart key system fuse: 2.0 A
ABS motor fuse: 30.0 A
Fuel injection system fuse:
7.5 A
ABS solenoid fuse: 15.0 A
ABS control unit fuse: 2.0 A
Backup fuse:
7.5 A
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Periodic maintenance an d a djustment
9-31
9
EAUN2261
Vehicle li ghtsThis model is equipped with LED lights
for headlights, auxiliary lights and
brake/tail light. If a light does not come
on, check the fuse and then have a
Yamaha dealer check the vehicle.NOTICE
ECA16581
Do not affix any type of tinted film or
stickers to the head light lens.
EAU43054
Replacin g a front turn si gnal
li g ht bul b1. Place the vehicle on the center-
stand.
2. Remove the turn signal light bulb socket (together with the bulb) by
turning it counterclockwise.
3. Remove the burnt-out bulb by pulling it out. 4. Insert a new bulb into the socket.
5. Install the socket (together with
the bulb) by turning it clockwise.
1. Headlight (high beam)
2. Headlight (low beam)
3. Auxiliary light
2
3
1
1. Turn signal light bulb socket
1
1. Turn signal light bulb
1
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Periodic maintenance an d a djustment
9-32
9
EAU67320
Replacin g a rear turn si gnal
lig ht bul b1. Open the seat. (See page 6-17.)
2. Remove the grab bar by removing
the bolts.
3. Remove the taillight cover by re- moving the screws. 4. Remove the turn signal light bulb
socket (together with the bulb) by
turning it counterclockwise.
5. Remove the burnt-out bulb by pulling it out. 6. Insert a new bulb into the socket.
7. Install the socket (together with
the bulb) by turning it clockwise.
8. Install the taillight cover by install- ing the screws.
9. Install the grab bar by installing the bolts, and then tightening them to
the specified torque.1. Grab bar
2. Bolt1
2
1. Taillight cover
2. Screw
1. Turn signal light bulb socket1 2
1
1. Turn signal light bulb
1
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Periodic maintenance an d a djustment
9-33
9 10. Close the seat.
EAU60701
Trou
bleshootin gAlthough 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 checkin g the fuel system, d o
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot lig hts from water heaters or furnaces. Gasoline or
g
asoline vapors can i gnite or ex-
plod e, causin g severe injury or prop-
erty damag e.
EAU76551
Smart key system trou bleshootin g
Please check the following items when
the smart key system does not work.  Is the smart key turned on? (See
page 3-4.)
 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 9-28.)
Tightenin g torque:
Grab bar bolt:
17 N·m (1.7 kgf·m, 13 lb·ft)
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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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Periodic maintenance an d a djustment
9-35
9 If the engine is left stopped by the
Stop and Start System for a long
period of time, the battery could
become discharged.
If the engine still does not restart after
you checked the preceding conditions,
have a Yamaha dealer check the vehi-
cle as soon as possible.
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Periodic maintenance an d a djustment
9-36
9
EAU86350
Trou bleshootin g chart
Check the fuel level in
the fuel tank.1. Fuel
There is enough fuel.
There is no fuel.
Check the battery.
Supply fuel.
The engine does not start.
Check the battery.
Try starting the engine.4. Compression
There is compression.
There is no compression.
The engine does not start.
Have a Yamaha dealer check the vehicle.Have a Yamaha dealer check the vehicle.
Remove the spark plug
and check the electrodes.3. Ignition
Wipe off with a dry cloth and correct the
spark plug gap, or replace the spark plug(s). Have a Yamaha dealer check the vehicle.
The engine does not start.
Check the compression.
Operate the electric starter.2. Battery
The engine turns over
quickly.
The engine turns over
slowly.
The battery is good.
DryWet
Try starting the engine.
Check the battery lead connections,
and charge the battery if necessary.
The engine does not start.
Check the ignition.
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Periodic maintenance an d a djustment
9-37
9
EAU86420
En gine overheatin g
WARNING
EWAT1041
Do not remove the ra diator cap when the en gine an d ra diator are hot. Scal din g hot flui d an d steam may be
b lown out un der pressure, which coul d cause serious injury. Be sure to wait until the en gine has cooled .
 Place a thick ra g, like a towel, over the ra diator cap, an d then slowly rotate the cap counterclockwise to the
d etent to allow any resi dual pressure to escape. When the hissin g soun d has stoppe d, press d own on the cap
while turnin g it counterclockwise, an d then remove the cap.TIPIf coolant is not available, tap water can be temporarily used instead, provided that it is changed to the recommended cool-
ant as soon as possible.
Wait until the
engine has cooled.
Check the coolant level in the
reservoir and radiator.
The coolant level
is OK.The coolant level is low.
Check the cooling system
for leakage.
Have a Yamaha dealer checkand repair the cooling system.Add coolant. (See TIP.)
Start the engine. If the engine overheats again,
have a
Yamaha dealer check
and repair the cooling system.
There is
leakage.
There is
no leakage.
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