Yamaha FJR1300AS(X) Service Manual page 565

Fault code No. 31
Diagnostic code No.
Order Item/components and probable
cause
5 The fuel pressure is too low.
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
FUEL INJECTION SYSTEM
Check or maintenance job
• Compare the fuel pressures at
idle and with throttle open.
• About the same → Normal
• Too low → Refer to the following
table.
• Check the fuel pump.
• Replace if defective.
Refer to "CHECKING THE
FUEL PUMP BODY" on page
7-2.
• Check the delivery hose for
pinching or kinking.
• Repair or replace if there is a
malfunction.
• Check the pressure regulator.
• Replace if defective.
Refer to "CHECKING THE
FUEL PRESSURE" on page
7-7.
• Check the throttle position sen-
sor.
• Execute the diagnostic mode.
(Code No.d:01)
• Replace if defective.
• Check the fuel system (discon-
nection, etc.).
• Repair or replace if there is a
malfunction.
• Check the intake system (im-
proper sealing, etc.).
• Repair or replace if there is a
malfunction.
8-88
Reinstatement
method