2005 YAMAHA VX110 electrical

7-10
E
–+ELECELECTRICAL ANALYSIS
Low resistance measurement
NOTE:
When measuring a resistance of 10 Ω
or less
using a digital tester, the correct measure-
ment cannot be obtained because of the
tester’s internal resistance.
To obtain the correct value, subtract the
internal resistance from the displayed mea-
surement.
The internal resistance of the tester can be
obtained by connecting both of its terminals.
Correct value =
Displayed measurement –
Internal resistance
Peak voltage measurement
NOTE:
When checking the condition of the ignition
system it is vital to know the peak voltage.
Cranking speed is dependant on many fac-
tors (e.g., fouled or weak spark plugs, a
weak battery). If one of these is defective,
the peak voltage will be lower than specifica-
tion.
If the peak voltage measurement is not
within specification the engine will not oper-
ate properly.
A low peak voltage will also cause compo-
nents to prematurely wear.
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7-11
E
–+ELECELECTRICAL ANALYSIS
Peak voltage adapter
NOTE:
Throughout this chapter the part numbers of
the specified peak voltage adapters have
been omitted. Refer to the following part
numbers.
The peak voltage adapter should be used
with a digital tester.
When measuring the peak voltage, connect
the peak voltage adapter to the digital circuit
tester and switch the selector to the DC volt-
age mode.
NOTE:
Make sure that the adapter leads are prop-
erly installed in the digital circuit tester.
Make sure that the positive pin (the “+” mark
facing up as shown) on the adapter is
installed into the positive terminal of the
tester.
The test harness is needed for the following
tests.
È Voltage measurement
É Peak voltage measurement
Test harness
NOTE:
If the lighting coil and pickup coil(s) are mea-
sured unloaded, disconnect the test harness
on the output side coupler.
Peak voltage adapter:
YU-39991
Peak voltage adapter B:
90890-03172
Checking steps:
Disconnect the coupler connections.
Connect the test harness between the
couplers.
Connect the tester terminals to the termi-
nals which are being checked.
Run the engine and observe the mea-
surement.È
É
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7-15
E
–+ELECIGNITION SYSTEM
IGNITION SYSTEM PEAK VOLTAGE
WARNING
When checking the electrical components,
do not touch any of the connections of the
digital tester lead wires.
NOTE:
If there is no spark, or the spark is weak,
continue with the ignition system test.
If a good spark is obtained, the problem is
not with the ignition system, but possibly with
the spark plug(s) or another component.
1. Measure:
ECM output peak voltage
Below specification →
Measure the
pickup coil output peak voltage.
NOTE:
When measuring the ECM output peak volt-
age while cranking the engine, disconnect
the ignition coil couplers for all cylinders
except for the cylinder being measured.
To crank the engine, connect the engine
shut-off cord (lanyard) to the engine shut-off
switch, and then press the start switch.
Test harness (2 pins):
New: YB-06867
Current: YB-06767
Test harness FWY-2 (2 pins):
New: 90890-06867
Current: 90890-06767
ECM output peak voltage:
Black/red (B/R) –
Red/yellow (R/Y)
Black/white (B/W) –
Red/yellow (R/Y)
Black/yellow (B/Y) –
Red/yellow (R/Y)
Black/green (B/G) –
Red/yellow (R/Y)
r/minLoaded
Cranking 2,000 3,500
V 90 130 140
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7-17
E
–+ELEC
NOTE:
To crank the engine, connect the engine shut-
off cord (lanyard) to the engine shut-off switch,
and then press the start switch and engine
stop switch simultaneously.
4. Measure:
Rectifier/regulator output voltage
Below specification →
Replace the recti-
fier/regulator.
NOTE:
Do not use the peak voltage adapter to mea-
sure the output voltage.
Disconnect the output lead of the tester har-
ness.
Test harness (6 pins):
YB-06848
Test harness FSW-6A (6 pins):
90890-06848
Rectifier/regulator output
voltage:
Red (R) – Black (B)
r/minUnloaded
3,500
V 13.0
BATTERY
Refer to “ELECTRICAL” in Chapter 3.
FUSE
Refer to “STARTING SYSTEM”.
SPARK PLUGS
Refer to “POWER UNIT” in Chapter 3.
IGNITION SYSTEM
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7-37
E
–+ELECSTARTING SYSTEM
BATTERY
Refer to “ELECTRICAL” in Chapter 3.
WIRING CONNECTIONS
1. Check:
Wiring connections
Poor connections →
Properly connect.
FUSES
1. Check:
Fuses
Broken →
Replace.
NOTE:
The 3 A fuse is for the remote control unit
(Deluxe model only).
The 10 A fuse is for the main and fuel pump
relay and the electronic control throttle valve
relay.
The 20 A fuse is for main and fuel pump relay.
The 30 A fuse is for the main relay.
Fuse ratings:
3 A, 10 A, 20 A, 30 A
START SWITCH
1. Check:
Continuity
Out of specification →
Replace.
Start switch continuity
(natural color coupler)
Clip PositionLeads
Red Brown
Installed Free
Push
Removed Free
Push
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7-44
E
–+ELECCHARGING SYSTEM
FUSE
Refer to “STARTING SYSTEM”.
BATTERY
Refer to “ELECTRICAL” in Chapter 3.
LIGHTING COIL
Refer to “IGNITION SYSTEM”.
RECTIFIER/REGULATOR
Refer to “IGNITION SYSTEM”.
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7-50
E
–+ELECINDICATION SYSTEM
FUSE
Refer to “STARTING SYSTEM”.
BATTERY
Refer to “ELECTRICAL” in Chapter 3.
MAIN AND FUEL PUMP RELAY
Refer to “IGNITION SYSTEM”.
ECM
Refer to “IGNITION SYSTEM”.
ENGINE TEMPERATURE SENSOR
Refer to “IGNITION SYSTEM”.
THERMOSWITCH (ENGINE)
Refer to “IGNITION SYSTEM”.
THERMOSWITCH (EXHAUST)
Refer to “IGNITION SYSTEM”.
REMOTE CONTROL UNIT
(DELUXE MODEL ONLY)
Refer to “REMOTE CONTROL SYS-
TEM (DELUXE MODEL ONLY)”.
BUZZER
1. Check:
Buzzer
Buzzer does not sound → Replace.
Checking steps:
Connect the battery (12 V) to the buzzer
coupler as shown.
Battery positive terminal →
Red (R) terminal 1
Battery negative terminal →
Black (B) terminal 2
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9-6
E
TRBL
ANLS
TROUBLE ANALYSIS
JET PUMP UNIT
Duct 6
Impeller 6
Intake grate 6
Bearings 6
Water inlet hose 6
Bilge hose 6
Bilge strainer 3
Bilge hose joint 6
ELECTRICAL
Ignition system, fuel control system
Pickup coils 7
ECM 7
Ignition coils 7
Slant detection switch 7
Engine stop switch 7
Engine shut-off switch 7
Spark plugs 3
Main and fuel pump relay 7
Electronic control throttle
valve relay7
Thermoswitch 7
Sensor assembly 7
Engine temperature
sensor7
Throttle body assembly
(throttle position sensor)7
Accelerator position
sensor7
Cam position sensor 7 Trouble mode Check elements
ENGINE WILL NOT START
HARD STARTING
ROUGH IDLING
HIGH IDLING
ENGINE STALLS
POOR ACCELERATION
ENGINE WILL NOT STOP
POOR PERFORMANCE
LIMITED ENGINE SPEED
OVERHEATING
LOW OIL PRESSURE
LOOSE STEERING
BILGE INCREASE
IRREGULAR WARNING INDICATION
POOR BATTERY CHARGING
Relative partReference
chapter
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