Yamaha WR450FB 2012, Owner'S Service Manual

Page: 348 / 392

FUEL INJECTION SYSTEM
9-44
TIP
Disconnect the fuel pump coupler when this diagnostic tool is used.
Fault code No. 39
Item Injector: open or short circuit detected.
Fail-safe system Unable to start engine
Unable to drive vehicle
Diagnostic code No. d:36
Actuation Actuates injector five times at one-second intervals.
The engine trouble warning light and the “WARNING” LED on the
diagnostic tool come on each time the fuel injector is actuated.
Procedure Check that injector is actuated five times by listening for the oper-
ating sound.
Or-
der
Probable cause of malfunc-
tion and check
Maintenance job
Confirmation of service
completion
1 Connection of injector cou-
pler.
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
o
Connect the coupler securely
or repair/replace the wire har-
ness.
Check for the operating
sound of the injector in the di-
agnostic mode (Code No.
d:36).
Operating sound heard
o
Go
to the order 7.
Operating sound unheard
o
Go to the order 2.
2 Defective injector. Measure the injector resis-
tance. If the resistance is not
12
:
, replace the injector.
Check for the operating
sound of the injector in the di-
agnostic mode (Code No.
d:36).
Operating sound heard
o
Go
to the order 7.
Operating sound unheard
o
Go to the order 3.
3 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
o
Connect the coupler securely
or repair/replace the wire har-
ness.
Check for the operating
sound of the injector in the di-
agnostic mode (Code No.
d:36).
Operating sound heard
o
Go
to the order 7.
Operating sound unheard
o
Go to the order 4.
4 Connection of sub wire har-
ness 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
o
Connect the coupler securely
or repair/replace the sub wire
harness.
Check for the operating
sound of the injector in the di-
agnostic mode (Code No.
d:36).
Operating sound heard
o
Go
to the order 7
Operating sound unheard
o
Go to the order 5.