Fail-Safe - Yamaha F30B 2018 Service Manual

Fail-safe

In the fail-safe control, the engine ECM enters the fail-safe control mode when an electrical component
malfunctions.
The fail-safe control system records the trouble codes according to the engine trouble conditions.
Trouble
code
15 Thermo sensor
18 TPS
19 Battery voltage
Intake air tempera-
23
ture sensor
27 Water in fuel filter
28 Shift position switch
Intake air pressure
29
sensor
37 Intake air passage
Engine shut-off
44
switch
Trouble conditions to be detect-
Item
Open or short circuit in the
thermo sensor circuit.
Output voltage is 0.2 V or less
or 4.9 V or more.
Open or short circuit in the
TPS circuit.
Output voltage is 0.3 V or less
or 4.7 V or more.
Voltage is 12 V or less for 2
minutes, even when engine
speed is 2000 r/min or more.
Open or short circuit in the in-
take air temperature sensor
circuit.
Output voltage is 0.4 V or less
or 4.8 V or more.
The shift position switch is on
and the water detection switch
is on.
Cranking while in gear.
Cranking while the shift posi-
tion switch circuit is open-cir-
cuited.
Open or short circuit in the in-
take air pressure sensor cir-
cuit.
Output voltage is 0.1 V or less
or 4.4 V or more.
The shift position switch is off,
the throttle is fully closed, the
ISC valve is fully closed, and
the engine speed is more than
1100 r/min.
Cranking when the clip is re-
moved.
ed
Control is performed based on
the intake air temperature
when starting.
Set to 40 C (104 F) when
running.
High engine idle speed.
Control is performed based on
the intake air pressure.
High engine idle speed.
High engine idle speed.
Set to 40 C (104 F).
High engine idle speed.
The alert buzzer sounds.
ECM does not control.
Control is performed based on
the TPS.
High engine idle speed.
Ignition timing is retarded to
limit the engine speed to 900 r/
min.
Ignition is skipped if the engine
speed does not decrease to
900 r/min even if ignition timing
is fully retarded.
Fuel injection is cut.
2-5
Electronic control system
Control and operation