Yamaha YZF-R6 99 Service Manual page 378

EAS00806
The speedometer fails to come on.
1. Speedometer bulb socket
S Check the speedometer bulb socket for con-
tinuity.
S Is the speedometer bulb socket OK?
YES
Replace the speedometer bulb
socket.
2. Voltage
S Connect the pocket tester (20 V DC) to the
speedometer coupler (wire harness side) as
shown.
Battery positive lead ! green/yellow
Battery negative lead ! black/blue
Battery positive lead ! red
NOTE:
First, connect the battery to the green/yellow
and black/blue
1 2
connect the battery positive lead to the
red/green 3 terminal.
When connecting the battery, check whether
the startup display 3 appears first and then af-
ter approximately three seconds the normal
display appears 4.
Does the startup display appear first and then
after approximately three seconds the normal
display appears?
YES
Replace the speedometer.
3. Voltage
S Connect the pocket tester (20 V DC) to the
speedometer bulb socket coupler (wire har-
ness side) as shown.
Tester positive probe ! blue
Tester negative probe ! blue/black
NO
1
2
3
coupler terminals, then
NO
1
2
SIGNALING SYSTEM
S Set the main switch to "ON".
S Measure the voltage (12 V) of blue
speedometer bulb socket coupler (wire har-
ness side).
S Is the voltage within specification?
YES
The wiring circuit from the main
switch to the speedometer bulb
socket coupler (wire harness
side) is faulty, repair it.
4. Speedometer sensor
S Connect the pocket tester (20 V DC) to the
speedometer coupler (wire harness side) as
shown.
Tester positive probe ! blue/yellow
Tester negative probe ! black/blue
S Set the main switch to "ON".
S Elevate the rear wheel and slowly rotate it.
S Measure the voltage (5 V) of blue/yellow and
black/blue. With each full rotation of the rear
wheel, the voltage reading should cycle from
0 V to 5 V to 0 V to 5 V.
S Does the voltage reading cycle correctly?
YES
This circuit is OK.
8-44
ELEC
1
on the
NO
1
2
NO
Replace the speedom-
eter sensor.