2004 YAMAHA YZF-R1S Service Manual

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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8-33
LIGHTING SYSTEMELEC
EAS00791
4. The auxiliary light fails to come on.
YESNO 1. Auxiliary light and socket

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

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

Connect the pocket tester (DC 20 V) to the
auxiliary light coupler (auxiliary light side) as
shown.
The wiring circuit
from the main switch
to the auxiliary light
coupler is faulty and
must be repaired. Positive tester probe
blue / red
Negative tester probe
black
1

Turn the main switch to “ON”.

Measure the voltage (DC 12 V) of blue / red
on the auxiliary light coupler (auxiliary
light side).

Is the voltage within specification?
2
This circuit is OK.
2
5. The turn signa l/ position light fails to come on.
YESNO 1. Turn signal / position light and socket

Check the turn signal / position light bulb and
socket for continuity.
Refer to “CHECKING THE BULBS AND
BULB SOCKETS”.

Are the turn signal / position light bulb and
socket OK?
Replace the turn sig-
nal / position light
bulb, socket or both.
YESNO 2. Voltage

Connect the pocket tester (DC 20 V) to the
turn signal / position light coupler (wire har-
ness side) as shown.
The wiring circuit from
the main switch to the
turn signal / position
light coupler is faulty
and must be repaired.
Turn the main switch to “ON”.

Measure the voltage (DC 12 V) of blue or
blue on the turn signal / position light cou-
pler (wire harness side).

Is the voltage within specification?
3
This circuit is OK.
Left turn signal / position light
Positive tester probe
blue
Negative tester probe
black
Right turn signal / position light
Positive tester probe
blue
Negative tester probe
black
1
2
A
Left turn signal / position light
Right turn signal / position light
B
A
B
3
4
1
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8-34
SIGNALING SYSTEMELEC
EAS00793
SIGNALING SYSTEM
CIRCUIT DIAGRAM
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8-35
SIGNALING SYSTEMELEC
1Main switch
4Fuse (main)
6Battery
10Starting circuit cut-off relay
11Neutral switch
13Fuel pump
14E.C.U.
27Speed sensor
38Fuel level warning light
39Oil level warning light
40Neutral indicator light
41Tachometer
42Shift timing indicator light
43Multi function meter
45Coolant temperature indicator light
47Turn signal indicator light (left)
48Turn signal indicator light (light)
55Turn signal relay
58Horn switch
60Turn signal switch
61Horn
62Front turn signal / position light (left)
63Front turn signal / position light (right)
64Rear turn signal light (left)
65Rear turn signal light (right)
73Fuse (ignition)
74Fuse (signal)
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8-36
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.
YESNO 1. Horn switch

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

Is the horn switch OK?
Replace the left han-
dlebar switch.
EAS00796
CHECKING THE SIGNALING SYSTEM
1. The horn fails to sound.
EAS00795
4. Wiring

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

Is the signaling system’s wiring properly
connected and without defects?
YESNO
Properly connect or
repair the signaling
system’s wiring.
Check the condition
of each of the signal-
ing system’s circuits.
Refer to “CHECK-
ING THE LIGHTING
SYSTEM”.
SIGNALING SYSTEMELEC
NOTE:
YESNO
1. Backup, main, ignition, signal and park
fuses

Check the backup, main, ignition, signal and
park fuses for continuity.
Refer to “CHECKING THE FUSES” in chap-
ter 3.

Are the backup, main, ignition, signal and
park fuses OK?
Replace the fuse(s).
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?
EAS00739EAS00794
TROUBLESHOOTING

Any of the following fail to light: turn sig-
nal light, brake light or an indicator light.

The horn fails to sound.
Check:
1. backup, main, ignition, signal, and park
fuses
2. battery
3. main switch
4. wiring connections
(of the entire signaling 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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8-37
SIGNALING SYSTEMELEC
YESNO 1. Tail / brake light bulb and socket

Check the tail / brake light bulb and socket for
continuity.
Refer to “CHECKING THE BULBS AND
BULB SOCKETS”.

Are the tail / brake light bulb and socket OK?
Replace the tail /
brake light bulb,
socket or both.
EAS007972. The tail / brake light fails to come on.
YESNO 2. Brake light switches

Check the brake light switches for continuity.
Refer to “CHECKING THE SWITCHES”.

Is the brake light switch OK?
Replace the brake
light switch.
3. Voltage

Connect the pocket tester (DC 20 V) to the
tail / brake light coupler (wire harness side)
as shown.
Positive tester probe
yellow
Negative tester probe
black
1
2

Turn the main switch to “ON”.

Pull in the brake lever or push down on the
brake pedal.

Measure the voltage (DC 12 V) of yellow
on the tail / brake light coupler (wire harness
side).

Is the voltage within specification?
1
YESNO 2. Voltage

Connect the pocket tester (DC 20 V) to the
horn connector at the horn terminal as
shown.
The wiring circuit
from the main switch
to the horn connec-
tor is faulty and must
be repaired. Positive tester probe
black / white
Negative tester probe
ground
1

Turn the main switch to “ON”.

Push the horn switch.

Measure the voltage (DC 12 V) of
black / white at the horn terminal.

Is the voltage within specification?
NOYES 3. Horn

Disconnect the black connector at the horn
terminal.

Connect a jumper lead to the horn termi-
nal and ground the jumper lead.

Turn the main switch to “ON”.

Push the horn switch.

Does the horn sound?
The horn is OK.
1
Replace the horn.
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8-38
SIGNALING SYSTEMELEC
NO
YESNO
The wiring circuit
from the main switch
to the tail / brake light
coupler is faulty and
must be repaired.
This circuit is OK.
YES 1. Turn signal indicator light (LEDs)

Check the turn signal indicator light for conti-
nuity.
Refer to “CHECKING THE LEDs”.

Are the turn signal indicator light OK?
Replace the meter
assembly.
EAS00799
3. The turn signal / position light, turn signal in-
dicator light or both fail to blink.
YES
2. Turn signal switch

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

Is the turn signal switch OK?
Replace the left han-
dlebar switch.
3. Voltage

Connect the pocket tester (DC 20 V) to the
turn signal relay coupler (wire harness side)
as shown.
Positive tester probe
brown
Negative tester probe
ground
1

Turn the main switch to “ON”.

Measure the voltage (DC 12 V) on brown
at the turn signal relay coupler (wire harness
side).

Is the voltage within specification?
1
YESNO
The wiring circuit
from the main switch
to the turn signal
relay coupler is faulty
and must be re-
paired.
YESNO 4. Voltage

Connect the pocket tester (DC 20 V) to the
turn signal relay coupler (wire harness side)
as shown.
The turn signal relay
is faulty and must be
replaced. Positive tester probe
brown / white
Negative tester probe
ground
1

Turn the main switch to “ON”.

Measure the voltage (DC 12 V) on
brown / white at the turn signal relay cou-
pler (wire harness side).

Is the voltage within specification?
1
NO
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8-39
SIGNALING SYSTEMELEC
C
YESNO
The wiring circuit
from the turn signal
switch to the turn sig-
nal light connector is
faulty and must be
repaired. Left turn signal / position light
Positive tester probe
chocolate
Negative tester probe
ground
Right turn signal / position light
Positive tester probe
dark green
Negative tester probe
ground
1
2

Turn the main switch to “ON”.

Set the turn signal switch to “ ” or “ ”.

Measure the voltage (DC 12 V) of the choco-
late or dark green at the turn signal light
connector (wire harness side).

Is the voltage within specification?
12
This circuit is OK.
AB
1. Neutral indicator light (LEDs)

Check the neutral indicator light for continu-
ity.
Refer to “CHECKING THE LEDs”.

Are the neutral indicator light OK?
EAS00801
4. The neutral indicator light fails to come on.
YESNO
Replace the meter
assembly.
YESNO 2. Neutral switch

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

Is the neutral switch OK?
Replace the neutral
switch.
3. Starting circuit cut-off relay (diode)

Disconnect the starting circuit cut-off relay
coupler from the wire harness.

Connect the pocket tester (Ω
1) to the
starting circuit cut-off relay coupler as
shown.

Check the starting circuit cut-off relay for
continuity.
Positive tester probe

blue / yellow
Negative tester probe

sky blue Continuity
Positive tester probe

sky blue
Negative tester probe

blue / yellow No
continuity
1
2
2
1
EAS00753
5. Voltage

Connect the pocket tester (DC 20 V) to the
turn signal light connector or meter assem-
bly coupler (wire harness side) as shown.
Left turn signal light
Right turn signal light
Turn signal indicator light
A
B
C
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