2005 YAMAHA VX110 Service Manual

7-22
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MAIN AND FUEL PUMP RELAY
1. Check:
• Main and fuel pump relay continuity
Faulty → Replace.
Checking steps:
 Connect the tester leads to the main and
fuel pump relay terminals 5 and 6 or 7.
 Connect terminals 2 or 3 to the positive
battery terminal.
 Connect terminal 1 to the negative bat-
tery terminal.
 Check that there is continuity between
the main and fuel pump relay terminals.
 Check that there is no continuity between
the main and fuel pump relay terminals
after disconnecting terminals 1, 2, or
3.
 Connect the tester leads between main
and fuel pump relay terminals 7 and 8.
 Connect terminals 4 to the negative bat-
tery terminal.
 Connect terminal 6 to the positive bat-
tery terminal.
 Check that there is continuity between
the main and fuel pump relay terminals.
 Check that there is no continuity between
the main and fuel pump relay terminals
after disconnecting terminals 4 or 6.
–+
8
7
6
5
4
3
2
1
–+
8
7
6
5
4
3
2
1
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7-23
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ELECTRONIC CONTROL THROTTLE
VALVE RELAY
1. Check:
Electronic control throttle valve relay
continuity
Faulty →
Replace.
Checking steps:
Connect the tester leads to the electronic
control throttle valve relay terminals 4
or
5
and 6
.
Connect terminals 2
or 3
to the positive
battery terminal.
Connect terminal 1
to the negative bat-
tery terminal.
Check that there is continuity between the
electronic control throttle valve relay ter-
minals.
Check that there is no continuity between
the electronic control throttle valve relay
terminals after disconnecting terminals
1
, 2
, or 3
.
–+
6
5
4
3
2
1
IGNITION SYSTEM
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7-24
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–+ELECIGNITION SYSTEM
THROTTLE POSITION SENSOR
1. Measure:
Throttle position sensor output voltage
Out of specification →
Replace the
throttle body assembly.
Checking steps:
CAUTION:
Do not loosen the throttle stop screw nut
and do not turn the throttle stop screw.
Connect a computer to the watercraft and
use the Yamaha Diagnostic System to
display the “throttle position sensor 1 out-
put voltage”, “throttle valve opening
angle”, and “throttle position sensor 2
output voltage”.
Release the throttle lever to the fully
closed position.
Check the output voltage of throttle posi-
tion sensor 1 and the throttle valve open-
ing angle.
1Throttle position sensor 1
2Throttle position sensor 2
ÈThrottle position sensor output voltage
ÉThrottle valve opening angle
ÊFully closed
ËFully open
NOTE:
The actual throttle position sensor output
voltage and throttle valve opening angle
may vary according to environmental condi-
tions.
Throttle position sensor 1 output
voltage with throttle lever fully
closed:
0.45–0.95 V (reference data)
Throttle valve opening angle with
throttle lever fully closed:
–1.1–9.4° (reference data)
2 ± 0.1 V
0.5 ± 0.05 V 4.65
± 0.05 V
(4.5 V)
(10˚)
É
ÊË È1 2
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7-25
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Squeeze the throttle lever to the fully
open position and hold it.
Check the output voltage of throttle posi-
tion sensor 2 and the throttle valve open-
ing angle.
Throttle position sensor 2 output
voltage with throttle lever fully
open:
4.60–4.70 V
Throttle valve opening angle with
throttle lever fully open:
above 80° (reference data)
Release the throttle lever from the fully
open position to the fully closed position
slowly and check the output voltage of
throttle position sensor 2 and the throttle
valve opening angle.
Hold the throttle lever when the output
voltage of throttle position sensor 2 is
below 4.5 V and the throttle valve open-
ing angle is above 10°.
Calculate the difference of the output
voltage of throttle position sensor 1 and
the output voltage of throttle position sen-
sor 2.
Throttle position sensor 2 output
voltage – throttle position sensor
1 output voltage = 1.9–2.1 V
Example:
If the output voltage of throttle position sen-
sor 1 is 2.5 V and the output voltage of
throttle position sensor 2 is 4.5 V, then
4.5 – 2.5 = 2.0 V
Operate the throttle lever and check that
the output voltage of throttle position sen-
sors 1 and 2 changes continuously.
NOTE:
The maximum output voltage of throttle
position sensor 2 is 4.65 ±
0.05 V at the half
open position.
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7-26
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–+ELECIGNITION SYSTEM
ACCELERATOR POSITION SENSOR
1. Measure:
Accelerator position sensor output volt-
age
Out of specification →
Replace the
accelerator position sensor.
Checking steps:
Connect a computer to the watercraft and
use the Yamaha Diagnostic System to
display the “accelerator position sensor
1” and “accelerator position sensor 2”.
Release the throttle lever to the fully
closed position.
Check that the accelerator position sen-
sor 1 and 2 output voltage.
NOTE:
The actual accelerator position sensor out-
put voltage and throttle valve opening angle
may vary according to environmental condi-
tions.
Accelerator position sensor 1
output voltage at throttle lever
fully closed position:
0.50–0.90 V
Accelerator position sensor 2
output voltage at throttle lever
fully closed position:
0.35–1.05 V
Throttle valve opening angle at
throttle lever fully closed
position:
2.7–4.8°
Squeeze the throttle lever to the fully
open position and hold it.
Check that the accelerator position sen-
sor 1 and 2 output voltage.
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7-27
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Accelerator position sensor 1
output voltage at throttle lever
fully opened position:
3.75–4.35 V
Accelerator position sensor 2
output voltage at throttle lever
fully opened position:
3.50–4.50 V
Throttle valve opening angle at
throttle lever fully opened
position:
above 61°
Calculate the difference of the accelera-
tor position sensor 1 output voltage and
accelerator position sensor 2 output volt-
age at fully opened position.
Accelerator position sensor 1
output voltage – Accelerator
position sensor 2 output voltage
at fully opened position = below
0.75 V
Example:
If accelerator position sensor 1 output volt-
age is 4.009 V and accelerator position sen-
sor 2 output voltage is 3.896 V, then 4.009
– 3.896 = 0.113 V
Operate the throttle lever, and check that
the accelerator position sensor 1 and 2
output voltage changes continuously.
IGNITION SYSTEM
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7-28
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2. Measure:
• Accelerator position sensor resistance
Out of specification →
Replace the
accelerator position sensor.
Checking steps:
 Connect the tester leads accelerator
position sensor terminals 1
, 3
.
 Measure the resistance when the fully
closed position.
Accelerator position sensor 1
resistance at fully closed
position:
0.50–0.90 kΩ
 Connect the tester leads accelerator
position sensor terminals 6
, 7
.
 Measure the resistance when the fully
closed position.
Accelerator position sensor 2
resistance at fully closed
position:
0.35–1.05 kΩ
 Move the accelerator position cam to the
fully opened position.
 Connect the tester leads accelerator
position sensor terminals 1
, 3
.
 Measure the resistance when the fully
opened position.
Accelerator position sensor 1
resistance at fully opened
position:
3.75–4.35 kΩ
 Connect the tester leads accelerator
position sensor terminals 6
, 7
.
 Measure the resistance when the fully
opened position.
Accelerator position sensor 2
resistance at fully opened
position:
3.60–4.50 kΩ
 Operate the accelerator cam, and check
that the accelerator position sensor 1 and
2 resistance changes continuously.
14
5678 3 2
14
5678 3 2
IGNITION SYSTEM
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7-29
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CAM POSITION SENSOR
1. Measure:
Cam position sensor output voltage
Out of specification →
Replace.
NOTE:
The cam position sensor consists of two indi-
vidual sensors as shown in the illustration:
sensor 1 1
and sensor 2 2
.
To measure the output voltage, pass a
screwdriver under the cam position sensor at
measuring points A, B (center), and C in this
order.
When operating the Yamaha Diagnostic Sys-
tem, electric power is supplied to the cam
position sensor.
Test harness (3 pins):
New: YB-06877
Current: YB-06777
Test harness HM090-3 (3 pins):
New: 90890-06877
Current: 90890-06777
Cam position sensor output
voltage:
Green/orange (G/O) –
Black/orange (B/O)
Position Voltage (V)
A More than 4.8
B Less than 0.8
C More than 4.8
Measurement steps:
Remove the cam position sensor.
Connect the test harness to the cam
position sensor.
Operate the Yamaha Diagnostic System.
Pass a screwdriver under the cam posi-
tion sensor in the direction shown and
measure the output voltage.
1
2
A
B
C
IGNITION SYSTEM
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