Yamaha XV1700P, XV1700PC. Service Manual - part 28

6 - 41

FI

FUEL INJECTION SYSTEM

CAUTION:

The throttle bodies should not be disas-
sembled unnecessarily.

CHECKING THE INJECTOR

1. Check:

• injector

Damage 

→

 Replace.

CHECKING THE THROTTLE BODY

1. Check:

• throttle body

Cracks/damage 

→

 Replace the throttle

bodies.

2. Check:

• fuel passages

Obstruction 

→

 Clean.

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a. Wash the throttle body in a petroleum-

based solvent.
Do not use any caustic carburetor cleaning
solution.

b. Blow out all of passages with compressed

air.

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6 - 42

FI

FUEL INJECTION SYSTEM

CHECKING THE FUEL PUMP AND 
PRESSURE REGULATOR OPERATION

1. Check:

• pressure regulator operation

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a. Remove the air duct.

Refer to “FUEL TANK” in chapter 3.

b. Remove the fuel hose end clamp 

1

.

c. Disconnect the fuel hose 

2

 from the fuel

injection pipe 

3

.

d. Connect the mity vac 

4

 onto the pipe 

5

onto the pressure regulator.

e. Connect the fuel pressure adapter 

6

 to the

pressure gauge 

7

.

f. Connect the fuel pressure adapter between

the fuel hose 

2

 and fuel injection pipe 

3

.

g. Start the engine.
h. Measure the fuel pressure.

i. Use the vacuum pressure pump gauge set

to adjust the fuel pressure in relation to the
vacuum pressure as described below.

NOTE:

The vacuum pressure should not exceed
100 kPa (1 mmHg).

Faulty 

→

 Replace the pressure regulator.

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Mity vac

YB-35956

Pressure gauge

YU-03153

Fuel pressure adapter

YM-03176

Fuel pressure

328 kPa (3.28 kg/cm

2

, 3.28 psi)

Increase the vacuum pressure 

→

Fuel pressure is decreased

Decrease the vacuum pressure 

→

Fuel pressure is increased

5

3

2

6 - 43

FI

AIR INDUCTION SYSTEM

EAS00507

AIR INDUCTION SYSTEM

AIR INJECTION

The air induction system burns unburned
exhaust gases by injecting fresh air (second-
ary air) into the exhaust port, reducing the
emission of hydrocarbons. 
When there is negative pressure at the
exhaust port, the reed valve opens, allowing
secondary air to flow into the exhaust port. The
required temperature for burning the unburned
exhaust gases is approximately 600 to 700 °C
(1,112 to 1,292 °F).

EAS00508

AIR CUT-OFF VALVE

The air cut-off valve is operated by the intake
gas pressure through the piston valve dia-
phragm. Normally, the air cut-off valve is open
to allow fresh air to flow into the exhaust port.
During sudden deceleration (the throttle valve
suddenly closes), negative pressure is gener-
ated and the air cut-off valve is closed in order
to prevent after-burning. 
Additionally, at high engine speeds and when
the pressure decreases, the air cut-off valve
automatically closes to guard against a loss of
performance due to self-EGR.

1

During normal operation, the air cut-off valve is
open. 

2

During sudden deceleration (the throttle valve
suddenly closes), the air cut-off valve closes. 

3

At high engine speeds and when the pressure
decreases, the air cut-off valve is closed.

È

From the air cleaner 

É

From the reed valve 

È

É

É

6 - 44

FI

AIR INDUCTION SYSTEM

AIR CUT-OFF VALVE ASSEMBLY AND AIR INDUCTION SYSTEM HOSES

3

2

6

5

7

4

2

1

T

 

R

.

.

10 Nm (1.0 m 

•

 

kg, 7.2 ft

 

•

 

Ib)

T

 

R

.

.

24 Nm (2.4 m 

•

 

kg, 17 ft

 

•

 

Ib)

Order

Job/Part

Q’ty

Remarks

Removing the air cut-off valve 
assembly and hoses

Remove the parts in the order listed.

Fuel hose joint 1/air duct

Refer to “FUEL TANK” in chapter 3.

1

Fuel hose joint

1

Disconnect.

2

Fuel hose

2

3

A.I.S. vacuum hose

1

4

Resonator hose

1

5

Reed valve case to front cylinder head 
hose

1

6

Reed valve case to rear cylinder head 
hose

1

7

Air cut-off valve assembly

1

For installation, reverse the removal 
procedure.

6 - 45

FI

AIR INDUCTION SYSTEM

REED VALVES

5

2

3

4

1

T

 

R

.

.

7 Nm (0.7 m

 

•

 kg, 5.1 ft 

•

 Ib)

6

Order

Job/Part

Q’ty

Remarks

Removing the reed valves

Remove the parts in the order listed.

Air cut-off valve assembly/hoses

1

A.I.S. vacuum hose

1

2

Reed valve cover

1

3

Reed valve assembly

1

4

Reed valve case

1

5

Pressure regulator

1

6

A.I.S. bracket

1

For installation, reverse the removal 
procedure.

6 - 46

FI

AIR INDUCTION SYSTEM

CHECKING THE PRESSURE REGULATOR

1. Check: 

• pressure regulator

Damage 

→

 Replace. 

EAS00510

CHECKING THE AIR INDUCTION SYSTEM

1. Check: 

• hoses 

Loose connection 

→

 Connect properly. 

Cracks/damage 

→

 Replace. 

• pipes 

Cracks/damage 

→

 Replace.

2. Check: 

• fiber reed 
• fiber reed stopper 
• reed valve seat 

Cracks/damage 

→

 Replace the reed valve.

3. Check: 

• air cut-off valve 

Cracks/damage 

→

 Replace.

7 - 1

–

+

ELEC

EAS00729

ELECTRICAL SYSTEM

ELECTRICAL COMPONENTS

1

Ignition coil 2

2

Ignition coil 1

3

Intake air pressure sensor 2

4

Front brake light switch

5

Main switch

6

Intake air pressure sensor 1

7

Clutch switch

8

Atmospheric pressure sensor

9

ECU

0

Battery

A

Fuel pump

B

Horn 2

C

Decompression solenoid

D

Sidestand switch

E

Crankshaft position sensor

F

Starter motor

G

Horn 1

H

Rectifier/regulator

1

2

3

4

5

6

7

8

0

A

B

C

D

E

F

G

H

9

ELECTRICAL COMPONENTS

1

2

3

4

5

6

7

7 - 2

–

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ELEC

ELECTRICAL COMPONENTS

1

Intake air temperature sensor

2

Linear control valve

3

Throttle position sensor

4

Engine temperature sensor

5

Spark plugs

6

Fuse box

7

Main fuse

8

Starter relay

9

Turn signal relay

0

Headlight relay

A

Relay unit

B

Speed sensor

C

Lean angle cut-off switch

D

Oil temperature sensor

E

Neutral switch

F

Stator coil assembly

G

Rear brake light switch

H

Cylinder identification sensor

1

5

2

3

4

5

6

7

0

A

B

C

D

E

F

G

H

9

8

7 - 3

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ELEC

ARRANGEMENT OF THE ELECTRICAL COMPONENTS

AND COUPLERS

ARRANGEMENT OF THE ELECTRICAL COMPONENTS AND COUPLERS

1

Speedometer coupler, tachometer couplers, right handlebar switch coupler and front turn signal/position
connectors

2

Speedometer coupler, main switch coupler and left handlebar switch couplers

3

Headlight coupler

1

Rear turn signal light (left) connectors and license plate light connectors

2

Rear turn signal light (right) connectors

3

Tail/brake light coupler

2

1

3

2

3

1

7 - 4

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ELEC

ARRANGEMENT OF THE ELECTRICAL COMPONENTS

AND COUPLERS

1

Linear control valve

2

Ignition coil 1 (rear cylinder)

3

Atmospheric pressure sensor

4

Atmospheric pressure sensor coupler

5

Spark plug cap (ignition coil 2 - L spark plug lead)

6

Spark plug cap (ignition coil 1 - L spark plug lead)

7

Crankshaft position sensor

8

Sidestand switch

9

Starter motor

0

Starter motor lead

A

Rectifier/regulator coupler

B

Stator coil assembly coupler

C

Horn 1 connectors

D

Horn 1

E

Rectifier/regulator

F

Linear control valve coupler

7

8

0 9

B

D

E

F

1

2

4

5

C

6

A

3

7 - 5

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ELEC

ARRANGEMENT OF THE ELECTRICAL COMPONENTS

AND COUPLERS

1

ECU coupler

2

ECU

3

Tail sub-wire harness coupler, decompression solenoid couplers, cylinder identification coupler, crankshaft
position sensor coupler, speed sensor coupler, neutral switch connector and sidestand switch coupler

4

Fuel pump coupler

5

Horn 2

6

Horn 2 coupler

7

Lean angle cut-off switch coupler

8

Lean angle cut-off switch

1

2

3

4

6

7

8

5

7 - 6

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ELEC

ARRANGEMENT OF THE ELECTRICAL COMPONENTS

AND COUPLERS

1

ECU fuse

2

Fuse box

3

Starter relay coupler

4

Main fuse

5

Starter relay

6

Turn signal relay

7

Battery

8

Battery positive lead

9

Headlight relay

0

Battery negative lead

A

Horn 2

B

Startr motor lead

C

Relay unit

2

C

6

3

2

1

0

8

7

4

4

5

5

9

A

6

A

A

B

7 - 7

–

+

ELEC

ARRANGEMENT OF THE ELECTRICAL COMPONENTS

AND COUPLERS

1

Spark plug cap (ignition coil 1 - R spark plug lead)

2

Throttle position sensor

3

Intake air pressure sensor 1 coupler 

4

Engine temperature sensor coupler

5

Intake air temperature sensor coupler

6

Intake air pressure sensor 2 coupler 

7

Main switch

8

Ignition coil 2 (front cylinder)

9

Spark plug cap (ignition coil 2 - R spark plug lead)

0

Rear brake light switch

A

Stator coil

B

Cylinder identification sensor

C

Decompression solenoid

D

Neutral switch

E

Oil temperature sensor coupler

F

Speed sensor

G

Ignition sub-wire harness coupler

1

2

3

4 5 6

7

8

9

0

A

B

C

D

E

F

G

7 - 8

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ELEC

CHECKING SWITCH CONTINUITY

EAS00730

CHECKING SWITCH CONTINUITY

Check each switch for continuity with the
pocket tester. If the continuity reading is incor-
rect, check the wiring connections and if nec-
essary, replace the switch.

CAUTION:

_ 

Never insert the tester probes into the cou-
pler terminal slots 

1

. Always insert the

probes from the opposite end of the cou-
pler, taking care not to loosen or damage
the leads. 

NOTE:

_ 

• Before checking for continuity, set the pocket

tester to “0” and to the “

Ω

 

×

 1” range. 

• When checking for continuity, switch back

and forth between the switch positions a few
times. 

The terminal connections for switches (e.g.,
main switch, engine stop switch) are shown in
an illustration similar to the one on the left. 
The switch positions 

a

 are shown in the far

left column and the switch lead colors 

b

 are

shown in the top row in the switch illustration.

NOTE:

_ 

“

” indicates a continuity of electricity

between switch terminals (i.e., a closed circuit
at the respective switch position). 

The example illustration on the left shows
that: 

There is continuity between red and brown/
blue and between blue/yellow and blue/black
when the switch is set to “ON”.

Pocket tester 

YU-03112

ON

OFF

R

Br

/

L

L

/

Y L

/

B

L

/

B

L

/

Y

Br

/

L

R

a

b

7 - 10

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ELEC

CHECKING THE SWITCHES

EAS00731

CHECKING THE SWITCHES

Check each switch for damage or wear, proper connections, and also for continuity between the ter-
minals. Refer to “CHECKING SWITCH CONTINUITY”.

Damage/wear 

→

 Repair or replace the switch. 

Improperly connected 

→

 Properly connect. 

Incorrect continuity reading 

→

 Replace the switch.

L

/

Y

B

/

Y

Ch

Dg

G

Y

(BLUE)

(BLACK)

R

L

/

B

Br

/

L

L

/

Y

R

/

W

B

L

/

W

R

/

B

G

/

Y

Br

(BLACK)

Br

G

/

Y

(BLUE)

B

B

Sb

(BLUE)

B

B

Y

G

R

/

Y

R

ON

OFF

Br

/

L

L

/

Y L

/

B

P B

R

/

B

R

/

W

B

L

/

W

L

/

Y

B

/

Y

B

Dg

Br

/

W

Y

/

R

(L)

N

(R)

Ch

R

/

Y

Y

/

R

P

Rr

/

W

B

1

2

3

4

5

6

7

8

9

0

A

B

7 - 11

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+

ELEC

CHECKING THE SWITCHES

1

Dimmer switch

2

Horn switch

3

Turn signal switch

4

Clutch switch

5

Engine stop switch

6

Start switch

7

Front brake light switch

8

Main switch

9

Fuse

0

Rear brake light switch

A

Neutral switch

B

Sidestand switch