Fail-Safe Control - Yamaha F150A Service Manual

Fail-safe control

If the electrical components malfunction, the ECM controls the ignition and fuel injection as shown in
the table.
Malfunctioning item
Pulser coil
Throttle position
sensor
Intake air pressure
sensor
Engine temperature
sensor
Intake air tempera-
ture sensor
Neutral switch
Thermoswitch
Shift cut switch
Oil pressure sensor
During fail-safe control, the engine idle speed increases to 900 r/min except if the neutral switch is
off when the outboard motor is started.
63P3F11
Details
No signal received during
four consecutive crankshaft
rotations
Output voltage is 0.3 V or
lower or 4.7 V or higher
Output voltage is 0.2 V or
lower or 4.5 V or higher
Output voltage is 0.18 V or
lower or 4.93 V or higher
Output voltage is 0.10 V or
lower or 4.61 V or higher
Switch is off when starting
the outboard motor
The switch is on when the
engine temperature is 40 °C
(104 °F) or lower or the
switch is off when the engine
temperature is 130 °C
(266 °F) or higher.
Output voltage is 4.50 V or
higher, the switch is on when
the outboard motor is
started, or both the shift cut
switch and neutral switch are
on for 5 seconds
Output voltage is 0.3 V or
lower or 4.8 V or higher
Ignition control
Fixed to BTDC 10° Fixed to BTDC 10°
Controlled accord- Controlled by Intake
ing to the basic air pressure and
injection map engine speed
Fuel injection vol-
ume is controlled by
Normal control
the throttle position
sensor
Normal control Normal control
Normal control Normal control
Normal control Normal control
Normal control Normal control
Normal control Normal control
Normal control Normal control
Technical tips
1
Fuel control
2
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5
6
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