Yamaha FJR1300AS(X) Service Manual page 564

Fault code No. 31
Diagnostic code No.
Order Item/components and probable
cause
1 Connections
• O sensor coupler
2
• Relay unit coupler
• Wire harness ECU coupler
• Sub-wire harness coupler
2 Open or short circuit in wire harness
and/or sub-wire harness.
3 Defective O
2
4 Clogged injector
Symptom The amount of air-fuel ratio feedback compensation is
maintained continuously in the vicinity of the upper limit
(lean air-fuel ratio).
d:01 Throttle position sensor
sensor
FUEL INJECTION SYSTEM
Check or maintenance job
• Check the coupler for any pins
that may be 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 O sensor coupler and
2
ECU coupler.
(black/blue–black/blue)
(gray/white–gray/white)
• Between O sensor coupler and
2
relay unit coupler.
(red/blue–red/blue)
• Between O sensor coupler and
2
sub-wire harness coupler.
(black–black)
Replace if defective. (Unable to
output a rich signal)
• Replace if defective.
Refer to "CHECKING THE IN-
JECTORS" on page 7-7.
8-87
Reinstatement
method
Starting the en-
gine, warming it
up until the
coolant temper-
ature is 60 °C
(140 °F) or
more, and then
running it be-
tween 2000–
3000 r/min un-
til the engine
trouble warn-
ing light turns
off.