Yamaha YZ450F Owner's Service Manual page 209

Fault code No.
Symptom
Fail-safe system
Diagnostic code No.
FI diagnostic tool display
Checking method
Item Item/components and probable cause
1 Check the connection and locking condition of
the atmospheric pressure sensor coupler.
Disconnect the coupler and check the pins.
(bent or broken terminals and locking condition
of the pins)
2 Check the connection and locking condition of
the wire harness ECU coupler.
Disconnect the coupler and check the pins.
(bent or broken terminals and locking condition
of the pins)
3 Continuity of harness
4 Installed condition of sensor.
23
Atmospheric pressure sensor signal is not received properly.
Able to start
Able to drive
D02
Atmosphere
Measure the atmospheric pressure.
FUEL INJECTION SYSTEM
Check or maintenance job
Poor connection → Properly con-
nect, repair, or replace.
Poor connection → Properly con-
nect, repair, or replace.
Open or short circuit → Replace.
Between atmospheric pressure
sensor coupler and ECU coupler.
(Black/Blue–Black/Blue)
(Pink–Pink)
(Blue–Blue)
Check that the sensor is installed
securely and that there are no
pinched leads.Check that the ECU
is installed securely and that there
are no pinched leads.
Incorrect installation → Reinstall
or repair.
7-23
Checking method
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 2.
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 3.
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 4.
Set the switch on the FI di-
agnostic tool sub-wire har-
ness to "ON", and then
check the fault code dis-
play.
Fault code number is not
displayed → Service is
finished.
Fault code number is dis-
played → Refer to item 5.