Yamaha FZS6W Service Manual page 351

Fault code No. 42 Symptom
Diagnostic code No.
Item/components and probable
Order
Connected state of connector
• Speed sensor coupler
• Main wire harness ECU coupler
A-1
Open or short circuit in speed sensor
lead.
A-2
Gear for detecting vehicle speed has
broken.
A-3
Defective speed sensor
A-4
Connected state of connector
• Neutral switch coupler
• Main wire harness ECU coupler
B-1
Open or short circuit in neutral switch
lead.
B-2
Faulty shift drum (neutral detection
B-3 area)
Defective neutral switch.
B-4
ANo normal signals are received from the speed sensor.
BOpen or short circuit is detected in the neutral switch.
A 07 Speed sensor
B 21 Neutral switch
cause
8-50
FUEL INJECTION SYSTEM
Check or maintenance job
• Check the coupler for any pins
that may have pulled out.
• Check the locking condition of
the coupler.
• If there is a malfunction, repair it
and connect the coupler
securely.
• Repair or replace if there is an
open or short circuit.
• Between speed sensor coupler
and ECU coupler.
(Blue–Blue)
(White/Yellow–White/Yellow)
(Black/Blue–Black/Blue)
• Replace if defective.
Refer to "CHECKING THE
SPEED SENSOR" on page 8-
78.
• Execute the diagnostic mode.
(Code No.07)
• Replace if defective.
Refer to "CHECKING THE
SPEED SENSOR" on page 8-
78.
• Check the coupler for any pins
that may have pulled out.
• Check the locking condition of
the coupler.
• If there is a malfunction, repair it
and connect the coupler
securely.
• Repair or replace if there is an
open or short circuit.
• Between neutral switch connec-
tor and relay unit coupler
(Sky blue–Sky blue)
• Replace if defective.
Refer to "TRANSMISSION" on
page 5-74.
• Execute the diagnostic mode.
(Code No.21)
• Replace if defective.
Refer to "CHECKING THE
SWITCHES" on page 8-63.
Reinstate-
ment method
Starting the
engine, and
inputting the
vehicle speed
signals by
operating the
vehicle at a 20
to 30 km/h.
Starting the
engine, and
inputting the
vehicle speed
signals by
operating the
vehicle at a 20
to 30 km/h.