Yamaha YZ 2018 Series, Owner'S Service Manual

Page: 332 / 402

FUEL INJECTION SYSTEM
8-33
1 Connection of throttle posi-
tion sensor coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness.
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is dis-
played

Go to item 2.
2 Connection of wire harness
ECU coupler.
Check the locking condition
of the coupler.
Disconnect the coupler and
check the pins (bent or bro-
ken terminals and locking
condition of the pins). Improperly connected

Connect the coupler securely
or repair/replace the wire har-
ness.
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is dis-
played

Go to item 3.
3 Wire harness continuity. Open or short circuit

Re-
place the wire harness.
Between throttle position
sensor coupler and ECU cou-
pler.
black/blue–black/blue
yellow–yellow
blue–blue
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is dis-
played

Go to item 4.
4 Installed condition of throttle
position sensor.
Check for looseness or
pinching. Improperly installed sensor

Reinstall or replace the
sensor.
Refer to “ADJUSTING THE
THROTTLE POSITION SEN-
SOR” on page 7-10.
Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is dis-
played

Go to item 5.
5 Applied voltage of throttle po-
sition sensor lead. Check the applied voltage.
(black/blue–blue) Push the start switch.
Fault code number is not dis-
played

Service is finished.
Fault code number is dis-
played

Go to item 6.
Location of discon-
nected lead Output
voltage
Disconnected
ground lead 5V
Disconnected out-
put lead 0V
Disconnected
power supply lead 0V
Fault code No. 15
Item Throttle position sensor: open or short circuit detected.