Yamaha YFM70RY Service Manual page 336

Fault code No. 42
Diagnostic code No.
Order Item/components and probable
cause
1 Connections
• Speed sensor coupler
• Main wire harness-ECU coupler
2 Open or short circuit in speed sensor
lead.
3 Gear for detecting vehicle speed has
broken.
4 Defective speed sensor
Symptom A. No normal signals are received from the speed sensor.
A d07 Speed sensor
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 se-
curely.
• Repair or replace if there is an
open or short circuit.
• Between speed sensor coupler
and ECU coupler.
(blue–blue)
(white–white)
(black/blue–black/blue)
• Replace if defective.
Refer to "TRANSMISSION" on
page 5-65.
• Execute the diagnostic mode.
(Code No. d07)
• Replace if defective.
Refer to "CHECKING THE
SPEED SENSOR" on page
8-71.
8-47
Reinstatement
method
Starting the en-
gine, and acti-
vating the
vehicle speed
sensor by oper-
ating the vehi-
cle at 20 to 30
km/h.