2005 YAMAHA VX110 electrical

3-20
E
INSP
ADJ
POWER UNIT
Spark plug inspection
1. Remove:
Ignition coils
CAUTION:
Be careful not to get any foreign sub-
stances or water in spark plug hole.
2. Inspect:
Electrodes 1

Damage/wear →
Replace.
Insulator color 2

Distinctly different color →
Check the
engine condition.
Color guide:
Medium to light tan color:
Normal
Whitish color:
Lean fuel mixture
Air leak
Incorrect settings
Blackish color:
Overly rich mixture
Electrical malfunction
Defective spark plug
3. Clean:
Spark plug
(with a spark plug cleaner or wire brush)
4. Measure:
Spark plug gap a

Out of specification →
Regap.
Spark plug gap:
0.7–0.8 mm (0.028–0.031 in)
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3-22
E
INSP
ADJ
ELECTRICAL
ELECTRICAL
Battery inspection
WARNING
Battery electrolyte is poisonous and dan-
gerous, causing severe burns, etc. Electro-
lyte contains sulfuric acid. Avoid contact
with skin, eyes or clothing.
Antidotes
External: Flush with water.
Internal: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten
egg or vegetable oil. Call physician immedi-
ately.
Eyes: Flush with water for 15 minutes and
get prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes, etc., well away. If
using or charging the battery in an
enclosed space, make sure that it is well
ventilated. Always shield your eyes when
working near batteries.
KEEP OUT OF THE REACH OF CHILDREN.
CAUTION:
Be careful not to place the battery on its
side.
Make sure to remove the battery from the
battery compartment when adding battery
electrolyte or charging the battery.
When checking the battery, make sure the
breather hose is connected to the battery
and not obstructed.
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3-23
E
INSP
ADJ
ELECTRICAL
1. Remove:
Bands
Battery negative lead 1

Battery positive lead 2

Battery
Battery breather hose 3

WARNING
When removing the battery, disconnect
the negative lead first.
Remove the battery to prevent acid loss
during turning the watercraft on its side
for the impeller, etc.
2. Inspect:
Electrolyte level
Low →
Add distilled water.
The electrolyte level should be between
the maximum a
and minimum b
level
marks.
CAUTION:
Use only distilled water. Other types of
water contain minerals which are harmful
to batteries.Filling steps:
Remove each filler cap.
Add distilled water to the maximum level
mark.
When the electrolyte level reaches the
maximum level mark, allow the cell to
stand for 20 minutes. If the electrolyte
level drops, add more distilled water so
the level reaches the maximum level
mark.
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3-24
E
INSP
ADJ
ELECTRICAL
3. Inspect:
Specific gravity
Out of specification →
Charge.
4. Install:
Filler caps
CAUTION:
Before installation, rinse off any fluid from
the battery box and battery and make sure
that the battery is dry before installing it.
Specific gravity at 20 °C (68 °F):
1.28
Charging current:
1.9 A
× 10 h
5. Install:
Battery breather hose 1

Battery
Battery positive lead 2

Battery negative lead 3

Bands
CAUTION:
Connect the positive lead to the battery
terminal first.
Make sure the battery leads are con-
nected properly. Reversing the leads can
seriously damage the electrical system.
Make sure that the battery breather hose is
properly connected and is not obstructed.
Coat the terminals with a water resistant
grease to minimize terminal corrosion.
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4-12
EFUEL
THROTTLE BODY ASSEMBLY AND INTAKE
MANIFOLD
SERVICE POINTS
Fuel hose clamps removal
1. Remove:
Fuel hose clamps
CAUTION:
If the fuel hose clamps are removed with-
out cutting the joint first, the fuel hose will
be damaged.
Hose clamps installation
1. Install:
Fuel hose clamps
WARNING
Do not reuse the fuel hose clamps, always
replace them with new ones.
NOTE:
Crimp the fuel hose clamps properly to
securely fasten them.
Fuel hose disconnection
WARNING
Before disconnecting the hose, remove the
fuel tank filler cap to reduce any pressure
inside the fuel tank, and then disconnect
the battery negative lead to cut off the elec-
tric current to the electrical systems.
1. Wrap the quick connector with a cloth, and
then rotate the quick connector tab 1
to
the stopper position a
.
WARNING
If the quick connector is removed sud-
denly, pressurized fuel could spray out. To
gradually release the fuel pressure, be sure
to remove the quick connector slowly.
1
a
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E
–+ELEC
1
2
3
4
5
6
7
8
9
CHAPTER 7
ELECTRICAL SYSTEM
ELECTRICAL COMPONENTS........................................................................ 7-1
FUSE BOX ....................................................................................................... 7-2
EXPLODED DIAGRAM ............................................................................. 7-2
REMOVAL AND INSTALLATION CHART ................................................ 7-2
ECM AND RECTIFIER/REGULATOR............................................................. 7-7
EXPLODED DIAGRAM ............................................................................. 7-7
REMOVAL AND INSTALLATION CHART ................................................ 7-7
ELECTRICAL ANALYSIS ............................................................................... 7-9
INSPECTION............................................................................................. 7-9
Digital tester ........................................................................................ 7-9
Low resistance measurement ........................................................... 7-10
Peak voltage measurement .............................................................. 7-10
Peak voltage adapter ........................................................................ 7-11
Test harness .................................................................................... 7-11
IGNITION SYSTEM ....................................................................................... 7-12
WIRING DIAGRAM ................................................................................. 7-12
IGNITION SPARK ................................................................................... 7-14
IGNITION SYSTEM PEAK VOLTAGE .................................................... 7-15
BATTERY ................................................................................................ 7-17
FUSE ....................................................................................................... 7-17
SPARK PLUGS ....................................................................................... 7-17
IGNITION COIL ....................................................................................... 7-18
ENGINE STOP SWITCH ......................................................................... 7-18
ENGINE TEMPERATURE SENSOR ...................................................... 7-19
SENSOR ASSEMBLY ............................................................................. 7-19
THERMOSWITCH (ENGINE).................................................................. 7-20
THERMOSWITCH (EXHAUST) .............................................................. 7-21
MAIN AND FUEL PUMP RELAY............................................................. 7-22
ELECTRONIC CONTROL THROTTLE VALVE RELAY ......................... 7-23
THROTTLE POSITION SENSOR ........................................................... 7-24
ACCELERATOR POSITION SENSOR ................................................... 7-26
CAM POSITION SENSOR ...................................................................... 7-29
SLANT DETECTION SWITCH ................................................................ 7-30
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7-1
E
–+ELECELECTRICAL COMPONENTS
ELECTRICAL COMPONENTS
O
N
M
L
K
J
I
H
G
F
E
D
C
B
A
0
91
2
3
4
5
6
7
8
1Thermoswitch (engine)
2Fuse box
3Slant detection switch
4Starter motor
5Engine temperature sensor
6Spark plugs and ignition coils
7Cam position sensor
8Battery
9Speed sensor
0Sensor assembly (intake air
pressure and intake air tem-
perature)AOil pressure switch
BFuel injectors
CThermoswitch (exhaust)
DRectifier/regulator
EECM
FThrottle body assembly
GLighting coil and pickup coil
HEngine stop switch, engine
shut-off switch, and start
switch
ISteering sensor
JBuzzerKAccelerator position sensor
LElectric fuel pump
MFuel sender
NMultifunction meter
ORemote control unit (Deluxe
model only)
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7-9
E
–+ELECELECTRICAL ANALYSIS
ELECTRICAL ANALYSIS
INSPECTION
CAUTION:
All measuring instruments should be han-
dled with special care. Damaged or mis-
handled instruments will not measure
properly.
On an instrument powered by dry batter-
ies, check the battery’s voltage periodi-
cally and replace the batteries if
necessary.
Digital tester
NOTE:
Throughout this chapter the part numbers of
the specified digital testers have been omitted.
Refer to the following part numbers.
NOTE:
“” indicates a continuity of electricity;
i.e., a closed circuit at the respective switch
position.
Digital multimeter:
YU-34899-A
Digital circuit tester:
90890-03174
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