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8To install the panel
1. Connect the coupler, and then place the pan-
el in the original position.
2. Install the quick fasteners.
3. Place the carrier in the original position, and then install the carrier bolts under the fenders.
4. Install the carrier top bolts, and then tighten all bolts to the specified torques. 5. Install the cover.
For YFM45KPXK / YFM45KPHK /
YFM45KPLK: Install the handlebar-mount-
ed light cover.
For YFM45KDXK / YFM45KDHK: Install
the handlebar cover.
6. Install the panels.
EBU23215Checking the spark plugThe 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 ac-
cordance with the periodic maintenance and lubri-
cation chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug 1. Remove the spark plug cap.
Tightening torques: Carrier bolt (top):34 N·m (3.4 kgf·m, 25 lb·ft)
Carrier bolt (under fenders): 7 N·m (0.7 kgf·m, 5.2 lb·ft)
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8
2. Remove the spark plug as shown, with the
spark plug wrench included in the 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 cap
1. Spark plug wrench
11
Specified spark plug:NGK/DR7EA
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8
WARNING
EWB02342Always let the exhaust system cool prior to
touching exhaust components.
Do not start the engine with the spark arrester
removed. Sparks or exhaust particulate can
cause eye injury, burns, or start a fire. 1. Remove the tailpipe bolts.
2. Remove the tailpipe by pulling it out of themuffler, and then remove the gasket. 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.
4. Check the gasket for damage. Replace if nec- essary.
5. Install the gasket onto the tailpipe, then insert the tailpipe into the muffler and align the bolt
holes.
6. Install the bolts and tighten to the specified torque.
EBU23921V-belt cooling duct check hoseIf dust or water collects in the V-belt cooling duct
check hose, remove the hose and clean it.
1. Gasket
2. Spark arrester
3. Tailpipe
4. Tailpipe bolt
3
2
4
1
4
Tightening torque:
Tailpipe bolt:10 N·m (1.0 kgf·m, 7.4 lb·ft)
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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
1
1. Rear brake light switch
2. Rear brake light switch adjusting nut
12
(a)
(b)
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8
For EPS models
1. Auxiliary DC jack fuse
2. Four-wheel-drive motor fuse
3. Ignition fuse
4. Radiator fan motor fuse
5. Signaling system fuse
6. Headlight fuse
7. Spare fuse
1
2
34
5
6
7
1. Fuel injection system spare fuse
2. Fuel injection system fuse
3. Main fuse
4. EPS fuse
5. Fuse box
1
2
3
4
5
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8If an electrical problem is suspected, check the
fuse and replace it if necessary as follows.
NOTICEECB00641To prevent accidental short-circuiting, turn off
the main switch when checking or replacing a
fuse. 1. Turn off all electrical systems. (See page 4-1.) 2. Remove the seat. (See page 4-13.)
3. 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]
1. Auxiliary DC jack fuse
2. Four-wheel-drive motor fuse
3. Ignition fuse
4. Radiator fan motor fuse
5. Signaling system fuse
6. Headlight fuse
7. Spare fuse
1
2
34
5
6
7
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8
4. Turn on the main switch, start the engine, and then turn on the circuit in question.
5. If the fuse immediately blows again, have a Yamaha dealer check the vehicle.
EBU34223Replacing a headlight bulbIf a headlight bulb burns out, replace it with the
specified bulb as follows.
Left and right headlight bulbs1. Remove the cover at the rear of the headlight by pulling it off.
2. Remove the bulb cover by pulling it off.
Specified fuses:
Main fuse:40.0 A
Headlight fuse: 15.0 A
Ignition fuse: 10.0 A
Four-wheel-drive motor fuse: 3.0 A
Signaling system fuse: 10.0 A
Radiator fan motor fuse: 20.0 A
Auxiliary DC jack fuse: 10.0 A
Fuel injection system fuse: 10.0 A
EPS fuse: 40.0 A (YFM45KPHK, YFM45KPLK,
YFM45KPXK)1. Cover at the rear of the headlight
1
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8
7. Install the bulb cover and the cover at the rear
of the headlight. NOTICE: Make sure the
bulb cover is securely fitted over the sock-
et and seated properly.
[ECB03320]
8. Adjust the headlight beam if necessary.
Handlebar-mounted light bulb (YFM45KPXK /
YFM45KPHK / YFM45KPLK) 1. Remove the handlebar-mounted light cover by removing the quick fasteners.
2. Remove the bulb cover by pulling it off. 3. Remove the socket by pushing it in and turn-
ing it counterclockwise.1. Handlebar-mounted light cover
2. Quick fastener
1
2
2
1. Bulb cover
1. Socket
1
1
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