Yamaha SR400 2014 Service Manual page 293

Fault code No.
Item
1 Throttle valve does not fully close.
2 The ISC valve is stuck fully open due to a
disconnected ISC unit or coupler. (High
engine idle speeds are detected with the
ISC valve stuck fully open even though
signals for the valve to close are continu-
ously being transmitted by the ECU.)
3 ISC valve is not moving correctly.
Reinstatement method
Fault code No.
Item
Fail-safe system
Diagnostic code No.
FI diagnostic tool display
Procedure
Probable cause of malfunction
1 Connections
• Lean angle sensor coupler
• Wire harness ECU coupler
37
ISC valve: engine speed is high when the engine is idling.
• Check the throttle body.
• Check the throttle cables.
• Check the ISC unit screw for looseness or
• Check the ISC unit coupler for disconnection.
• The ISC valve is stuck fully open if it does not
• Execute diagnostic code No. D54.
• After the ISC valve is fully closed, the valve
Turn the main switch to "ON" and back to "OFF" to return the ISC
valve to its original position, and then start the engine.
After starting, let the engine run at idle speed for about 10 sec-
onds.
41
Lean angle sensor: open or short circuit detected.
Unable to start engine
Unable to drive vehicle
D08
Lean angle sensor output voltage
• 3.6–4.5 (upright)
• 0.7–1.4 (overturned)
Remove the lean angle sensor and incline it more than 45
degrees.
• Check the coupler for any pins that may be
• Check the locking condition of the coupler.
• If there is a malfunction, repair it and connect
7-36
FUEL INJECTION SYSTEM
Refer to "THROTTLE BODY" on page 6-9.
Refer to "CHECKING THE THROTTLE
GRIP" on page 3-24.
disconnection.
operate when the main switch is set to
"OFF".
(Make sure that the ISC unit vibrates by
touching it. If the ISC valve is vibrating, it is
working normally.)
opens to the standby opening position (posi-
tion when the engine is started). This opera-
tion takes approximately 3 seconds until it is
completed. Start the engine. If the error
recurs, replace the throttle body assembly.
Check or maintenance job
pulled out.
the coupler securely.