2016 YAMAHA GRIZZLY 450 light

8-15
8
3. Remove the spark plug as shown, with the
spark plug wrench included 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 medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).
TIPIf the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV. 2. Check the spark plug for electrode erosionand excessive carbon or other deposits, and
replace it if necessary.
3. Measure the spark plug gap with a wire thick- ness gauge and, if necessary, adjust the gap
to specification.
1. Spark plug wrench
Specified spark plug:NGK/DR8EA
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8
case. Never operate the engine with the air
filter element removed. This will allow un-
filtered air to enter the engine, causing
rapid engine wear and possible engine
damage. Additionally, operation without
the air filter element will affect carburetor
jetting with subsequent poor performance
and possible engine overheating.
[ECB00462]
12. Install the seat.TIPThe air filter element should be cleaned every 20–
40 hours. It should be cleaned and lubricated
more often if the ATV is operated in extremely
dusty areas. Each time the air filter element main-
tenance is performed, check the air inlet of the air
filter case for obstructions. Check the air filter
case rubber joint to the carburetor fittings and the
rubber joint manifold fittings for an air-tight seal.
Tighten all fittings securely to avoid the possibility
of unfiltered air entering the engine. EBU27083Cleaning the spark arresterBe sure the exhaust pipe and muffler are cool be-
fore cleaning the spark arrester.
1. Remove the tailpipe bolts. 2. Remove the tailpipe by pulling it out of the
muffler.
3. Tap the tailpipe lightly, and then use a wire brush to remove any carbon deposits from
the spark arrester portion of the tailpipe and
inside of the tailpipe housing.
1. Tailpipe bolt
2. Tailpipe
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8
EBU29882Brake light switchesThe brake light, which is activated by the brake
pedal and brake levers, should come on just be-
fore braking takes effect.
The rear brake light switch for the brake pedal can
be adjusted as follows, but the other brake light
switches should be adjusted by a Yamaha dealer.
Turn the rear brake light switch adjusting nut while
holding the brake light switch in place. To make
the brake light come on earlier, turn the adjusting
nut in direction (a). To make the brake light come
on later, turn the adjusting nut in direction (b).
1. Front axle boot (each side)
1. Rear axle boot (each side)
1
1
1. Rear brake light switch
2. Rear brake light switch adjusting nut
1
2(b)
(a)
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8
EBU30801Replacing a fuseThe main fuse, the EPS fuse, and the fuse box are
located under the seat. (See page 4-19.)
For non-EPS models1. Main fuse
2. Fuse box
3. Spare main fuse
1
2
3
1. Headlight fuse
2. Ignition fuse
3. Auxiliary DC jack fuse
4. Four-wheel-drive motor fuse
5. Signaling system fuse
6. Backup fuse (for clock)
7. Spare fuse
1
2
3
4
5
6
7
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8For EPS models
If a fuse is blown, replace it as follows.1. Turn the key to “OFF” and turn off all electrical circuits.
NOTICEECB00641To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse.
1. Main fuse
2. Fuse box
3. EPS fuse
4. Spare main fuse
12
3
4
1. Headlight fuse
2. Signaling system fuse
3. Ignition fuse
4. Four-wheel-drive motor fuse
5. Backup fuse (for clock)
6. Auxiliary DC jack fuse
7. Spare fuse
1
2
3
4
5
6
7
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8
2. Remove the blown fuse, and then install a
new fuse of the specified amperage.
WARNING! Always use a fuse of the spec- ified rating, and never use a substitute ob-
ject in place of the proper fuse. An
improper fuse or a substitute object can
cause damage to the electrical system,
which could lead to a fire.
[EWB02173]
3. Turn the key to “ON” and turn on the electrical circuits to check if the devices operate.
4. If the fuse immediately blows again, have a Yamaha dealer check the electrical system.EBU25482Replacing a headlight bulbIf a headlight bulb burns out, replace it as follows.Specified fuses:
Main fuse:30.0 A
Headlight fuse: 15.0 A
Ignition fuse: 10.0 A
Four-wheel-drive motor fuse: 10.0 A
Signaling system fuse: 10.0 A
Auxiliary DC jack fuse: 10.0 A
Backup fuse: 10.0 A (YFM45GDXG)
5.0 A (YFM45GPHG, YFM45GPXG)
EPS fuse: 40.0 A (YFM45GPHG, YFM45GPXG)
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81. Remove the cover at the rear of the headlight
by pulling it off.
2. Remove the headlight bulb holder cover by pulling it off. 3. Remove the headlight bulb holder by pushing
it in and turning it counterclockwise.
1. Cover at the rear of the headlight
1. Headlight bulb holder cover
1. Headlight bulb holder
1
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8
4. Remove the burnt-out bulb by pulling it out.
5. Insert a new headlight bulb into the bulb hold-
er by pushing it in. NOTICE: Do not touch
the glass part of the headlight bulb to keep
it free from oil, otherwise the transparency
of the glass, the luminosity of the bulb, and
the bulb life will be adversely affected.
Thoroughly clean off any dirt and finger-
prints on the headlight bulb using a cloth
moistened with alcohol or thinner.
[ECB00652]
6. Install the bulb holder by pushing it in and turning it clockwise. 7. Install the bulb holder cover and the cover at
the rear of the headlight. NOTICE: Make
sure the headlight bulb holder cover is se-
curely fitted over the bulb holder and seat-
ed properly.
[ECB00672]
8. Adjust the headlight beam if necessary.EBU25553Adjusting a headlight beamNOTICEECB00691It is advisable to have a Yamaha dealer make
this adjustment. To raise a headlight beam, turn the headlight
beam adjusting screw in direction (a).
To lower a headlight beam, turn the adjusting
screw in direction (b).
1. Do not touch the glass part of the bulb.U2LC62E0.book Page 59 Monday, May 11, 2015 2:28 PM