Yamaha F150B, Service Manual

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2-17
TECH
FEA
Technical features and description
Fail-safe control
If the electrical components malfunction, the engine ECM controls the ignition and fuel injection as
shown in the table.
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.
Trouble
code
Malfunction
components
Criterion Ignition control Fuel injection control
13 Pulser coil No signal received during four
consecutive crankshaft rota-
tions Fixed to BTDC 10° Fixed to BTDC 10°
15 Engine temper-
ature sensor Output voltage is less 0.18 V or
more 4.93 V Normal control Normal control
18 TPS Output voltage is less 0.3 V or
more 4.7 V Controlled according to
the basic ignition map Controlled by intake air
pressure and engine
speed
23 Air temperature
sensor Output voltage is less 0.10 V or
more 4.61 V Normal control Normal control
28 Neutral switch Switch is off when starting the
engine Normal control Normal control
29 Air pressure
sensor Output voltage is less 0.2 V or
more 4.5 V Normal control Fuel injection volume is
controlled by the TPS
39 Oil pressure
sensor Output voltage is less 0.3 V or
more 4.8 V Normal control Normal control
45 Shift cut switch Output voltage is more 4.5 V,
the switch is on when the
engine is started, or both the
shift cut switch and neutral
switch are on for 5 seconds Normal control Normal control
46 Thermoswitch The switch is on when the
engine temperature is less
40 °C (104 °F) or the switch is
off when the engine tempera-
ture is more 130 °C (266 °F) Normal control Normal control