Yamaha YZ250FX 2021, Owner'S Service Manual

Page: 315 / 378

FUEL INJECTION SYSTEM
8-28
Fault code No. 16
TIP
• If fault code numbers 15 and 16 are both displayed, perform checkup and repair jobs for fault code
number 15 first.
• Before troubleshooting, disconnect the starter motor lead from the starter relay.
5 Applied voltage of throttle posi-
tion sensor lead.
Check the applied voltage.
(black/blue–blue)
Start switch to ON (main relay
ON), and then check the condi-
tion of the fault code using the
malfunction mode of the
Yamaha diagnostic tool.
Condition is “Recovered”

Go
to item 8 and finish the service.
Condition is “Detected”

Go to
item 6.
Location of discon-
nected lead
Output
voltage
Disconnected
ground lead
5 V
Disconnected output
lead
0 V
Disconnected power
supply lead
0 V
6 Defective throttle position sen-
sor.
Execute the diagnostic mode.
(Code No. 01)
When the throttle is fully closed,
11–14 displays.
When the throttle is fully
opened, 86–92 displays.
Incorrect display range

Replace the throttle position
sensor.
Start switch to ON (main relay
ON), and then check the condi-
tion of the fault code using the
malfunction mode of the
Yamaha diagnostic tool.
Condition is “Recovered”

Go
to item 8 and finish the service.
Condition is “Detected”

Go to
item 7.
7 Faulty ECU. Replace the ECU. Service is finished.
8 Delete the fault code. Confirm that the fault code has
a condition of “Recovered”
using the Yamaha diagnostic
tool, and then delete the fault
code.
Fault code No. 16
Item Throttle position sensor: stuck throttle position sensor is detected.
Fail-safe system
Able to start engine
Able to drive vehicle
Diagnostic code No.
01
Diagnostic tool display
Displays the throttle angle.
•
11–14 (throttle in fully closed position)
•
86–92 (throttle in fully opened position)
Procedure
•
Check with throttle fully closed.
•
Check with throttle fully opened.
Item
Probable cause of malfunc-
tion and check
Maintenance job
Confirmation of service com-
pletion
Fault code No. 15
Item Throttle position sensor: open or short circuit detected.