Yamaha WR250R Service Manual page 320

Fault code No. 42
Diagnostic monitoring
code No.
Order Item/components and probable cause
A-1 Installed condition of speed sensor
A-2 Connected state of connector.
Speed sensor coupler
G
Wire harness ECU coupler
G
A-3 Open or short circuit in speed sensor
lead.
A-4 Defective speed sensor.
A. No normal signals are received from the speed sensor.
Symptom
B. Open or short circuit is detected in the neutral switch.
A 07 Speed sensor
B 21 Neutral switch
Check or maintenance job
G
G
G
G
G
G
(Blue–Blue)
(White–White)
(Black/Blue–Black/Blue)
G
G
Refer
SPEED SENSOR" on page 8-77.
8-49
FUEL INJECTION SYSTEM
Check the installed area for loose-
ness or pinching.
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 it securely.
Repair or replace if there is an
open or short circuit.
Between sensor coupler and ECU
coupler.
Execute the diagnostic monitoring
mode. (Code No.07)
Replace if defective.
to "CHECKING
Reinstatement
method
Starting the
engine, and
inputting the
vehicle speed
signals by oper-
ating the motor-
cycle at a low
speed of 20–30
km/h.
THE