2004 YAMAHA YZF-R1SC wiring

8-16
YESNO
3. Starter motor

Connect the positive battery terminal and
starter motor lead with a jumper lead .
Repair or replace the
starter motor.
A wire that is used as a jumper lead
must have at least the same capacity or
more as that of the battery lead, other-
wise the jumper lead may burn.

This check is likely to produce sparks,
therefore make sure nothing flammable
is in the vicinity.

Does the starter motor turn?
WARNING
1
23
EAS00758
YESNO 2. Battery

Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in chapter 3.
Minimum open-circuit voltage
12.8 V or more at 20C (68F)

Is the battery OK?

Clean the battery
terminals.

Recharge or re-
place the battery.
EAS00739
ELECTRIC STARTING SYSTEMELEC
NOTE:
YESNO
1. Main and ignition fuses

Check the main and ignition fuses for conti-
nuity.
Refer to “CHECKING THE FUSES” in chap-
ter 3.

Are the main and ignition fuses OK?
Replace the fuse(s).
EAS00757
TROUBLESHOOTING
The starter motor fails to turn.
Check:
1. main and ignition fuses
2. battery
3. starter motor
4. starting circuit cut-off relay
5. starter relay
6. main switch
7. engine stop switch
8. neutral switch
9. sidestand switch
10. clutch switch
11. start switch
12. wiring connections
(of the entire starting system)

Before troubleshooting, remove the following
part(s):
1. seat
2. fuel tank
3. side cowlings
4. throttle body assembly

Troubleshoot with the following special tool(s).
Pocket tester
90890-03112, YU-3112
EAS00738
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8-18

Check the entire starting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.

Is the starting system’s wiring properly con-
nected and without defects?
EAS00766
12. Wiring
YESNO
Properly connect or
repair the starting
system’s wiring.
The starting system
circuit is OK.
11. Start switch

Check the start switch for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the start switch OK?
YESNO
Replace the right
handlebar switch.
EAS00764
10. Clutch switch

Check the clutch switch for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the clutch switch OK?
YESNO
Replace the clutch
switch.
EAS00763EAS00752
9. Sidestand switch

Check the sidestand switch for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the sidestand switch OK?
YESNO
Replace the side-
stand switch.
ELECTRIC STARTING SYSTEMELEC
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8-25
NOYES
3. Charging voltage

Set the engine tachometer to the ignition coil
of cylinder #1.

Connect the pocket tester (DC 20 V) to the
battery as shown.
The charging circuit
is OK. Positive tester probe

positive battery terminal
Negative tester probe

negative battery terminal

Start the engine and let it run at approxi-
mately 5,000 r / min.

Measure the charging voltage.
Charging voltage
14 V at 5,000 r / min

Is the charging voltage within specification?
EAS00775
YESNO

Clean the battery
terminals.

Recharge or re-
place the battery.
Make sure the battery is fully charged.
NOTE:
Minimum open-circuit voltage
12.8 V or more at 20C (68F)

Is the battery OK?
CHARGING SYSTEMELEC
NOTE:
YESNO
1. Main fuse

Check the main fuse for continuity.
Refer to “CHECKING THE FUSES” in chap-
ter 3.

Is the main fuse OK?
Replace the fuse.
2. Battery

Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in chapter 3.
EAS00739 EAS00774
TROUBLESHOOTING
The battery is not being charged.
Check:
1. main fuse
2. battery
3. charging voltage
4. stator coil lead
5. stator coil resistance
6. wiring connections
(of the entire charging system)

Before troubleshooting, remove the following
part(s):
1. seat
2. fuel tank

Troubleshoot with the following special tool(s).
Pocket tester
90890-03112, YU-3112
EAS00738
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8-26
CHARGING SYSTEMELEC
YESNO 5. Stator coil resistance

Remove the generator cover.

Connect the pocket tester (Ω
1) to the sta-
tor coils as shown.
Replace the stator
coil assembly.
EAS00776
Positive tester probe
white
Negative tester probe
white
Positive tester probe
white
Negative tester probe
white1
1
2
3

Measure the stator coil resistances.
Stator coil resistance
0.14  0.18 Ω at 20C (68F)

Is the stator coil OK?
YESNO 6. Wiring

Check the wiring connections of the entire
charging system.
Refer to “CIRCUIT DIAGRAM”.

Is the charging system’s wiring properly con-
nected and without defects?
Properly connect or
repair the charging
system’s wiring.
EAS00779
Replace the rectifi-
er / regulator.
4. Stator coil lead

Disconnect stator coil lead coupler.

Connect the pocket tester (Ω
1) to the sta-
tor coil lead coupler as shown.
Positive tester probe

white
Negative tester probe

ground
3
Positive tester probe

white
Negative tester probe

ground
1
Positive tester probe

white
Negative tester probe

groundNo
continuity
2
YESNO
Replace the stator
coil lead.
Are the tester readings correct?
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8-29
YESNO

Clean the battery
terminals.

Recharge or re-
place the battery.
EAS00749
3. Main switch

Check the main switch for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the main switch OK?
YESNO
Replace the main
switch.
EAS00784
YESNO 4. Dimmer switch

Check the dimmer switch for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the dimmer switch OK?
The dimmer switch is
faulty. Replace the
left handlebar switch.
Minimum open-circuit voltage
12.8 V or more at 20C (68F)

Is the battery OK?
LIGHTING SYSTEMELEC
NOTE:
YESNO
1. Main, turn and headlight fuses

Check the main, turn and headlight fuses for
continuity.
Refer to “CHECKING THE FUSES” in chap-
ter 3.

Are the main, turn and headlight fuses OK?
Replace the fuse(s).
2. Battery

Check the condition of the battery.
Refer to “CHECKING AND CHARGING
THE BATTERY” in chapter 3.
EAS00739EAS00781
TROUBLESHOOTING
Any of the following fail to light: headlight,
high beam indicator light, taillight, licence
light or meter light.
Check:
1. main, turn and headlight fuses
2. battery
3. main switch
4. dimmer switch
5. pass switch
6. headlight relay (on / off)
7. headlight relay (dimmer)
8. wiring connections
(of the entire lighting system)

Before troubleshooting, remove the following
part(s):
1. seat
2. fuel tank
3. side cowlings

Troubleshoot with the following special tool(s).
Pocket tester
90890-03112, YU-3112
EAS00738
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8-30

Does the Headlight relay (dimmer) have
continuity between red / yellow and
black / green ?
NOYES
Replace the dimmer
relay. Positive tester probe
red / yellow
Negative tester probe
black / green
1
2
3
4
5. Headlight relay (on / off)

Disconnect the headlight relay (on / off) from
the coupler.

Connect the pocket tester (Ω
1) and bat-
tery (12 V) to the headlight relay (on / off) as
shown.
Positive battery lead
red / yellow
Negative battery lead
yellow / black
EAS00787
YESNO 7. Wiring

Check the entire lighting system’s wiring.
Refer to “CIRCUIT DIAGRAM”.

Is the lighting system’s wiring properly con-
nected and without defects?
Properly connect or
repair the lighting
system’s wiring.
Check the condition
of each of the lighting
system’s circuits.
Refer to “CHECK-
ING THE LIGHTING
SYSTEM”.

Does the headlight relay (dimmer) have
continuity between black / green and
black / yellow ?
Positive tester probe
black / green
Negative tester probe
black / yellow
1
2
3
4
6. Headlight relay (dimmer)

Disconnect the headlight relay (dimmer)
from the coupler.

Connect the pocket tester (Ω
1) and bat-
tery (12 V) to the headlight relay (dimmer) as
shown.
Positive battery lead
black
Negative battery lead
yellow
3
4
3
4
YESNO
Replace the head-
light relay (dimmer).
LIGHTING SYSTEMELEC
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8-31
High beam indicator light (LEDs)
Positive tester probe
black / yellow
Negative tester probe

black / white
YESNO 1. Headlight bulb and socket

Check the headlight bulb and socket for con-
tinuity.
Refer to “CHECKING THE BULBS AND
BULB SOCKETS”.

Are the headlight bulb and socket OK?
Replace the head-
light bulb, socket or
both.
YESNO 2. Voltage

Connect the pocket tester (DC 20 V) to the
headlight and meter assembly couplers as
shown.
The wiring circuit
from the main switch
to the headlight cou-
pler is faulty and
must be repaired.
When the dimmer switch is set to “ ”
When the dimmer switch is set to “ ”
Headlight coupler (wire harness side)
Low beam
Headlight
Positive tester probe
black
Negative tester probe
black / green
1
2
Meter assembly coupler (wire harness side)

Turn the main switch to “ON”.

Start the engine.

Set the dimmer switch to “ ” or “ ”.

Measure the voltage (DC 12 V) of
black / green or black / yellow on the
headlight coupler (wire harness side).

Is the voltage within specification?
2
This circuit is OK.
A
B
Headlight
Positive tester probe
black
Negative tester probe
black / yellow
A
Headlight coupler (wire harness side)
High beam
B
6
5
3
4
4
LIGHTING SYSTEMELEC
EAS00788
CHECKING THE LIGHTING SYSTEM
1. The headlight and the high beam indicator
light fail to come on.
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8-32
LIGHTING SYSTEMELEC
YESNO 1. License plate light bulb and socket

Check the license plate light bulb and socket
for continuity.
Refer to “CHECKING THE BULBS AND
BULB SOCKETS”.

Are the license plate light bulb and socket
OK?
Replace the license
plate light bulb, sock-
et or both.
EAS007922. The license plate light fails to come on.
YESNO 2. Voltage

Connect the pocket tester (DC 20 V) to the
license plate light coupler (wire harness light
side) as shown.
The wiring circuit
from the main switch
to the license plate
light coupler is faulty
and must be re-
paired. Positive tester probe
blue / red
Negative tester probe
black
1
2

Turn the main switch to “ON”.

Measure the voltage (DC 12 V) of blue / red
on the license plate light coupler (wire
harness side).

Is the voltage within specification?
1
This circuit is OK.
EAS00790
3. The tail / brake light fails to come on.
YESNO 1. Voltage

Connect the pocket tester (DC 20 V) to the
tail / brake light coupler (wire harness side)
as shown.
Wiring circuit from
the main switch to
the tail / brake light
coupler is faulty and
must be repaired. Positive tester probe
blue / red
Negative tester probe
black
1
2

Turn the main switch to “ON”.

Measure the voltage (DC 12 V) of blue / red
on the tail / brake light coupler (wire har-
ness side).

Is the voltage within specification?
1
This circuit is OK.
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