Yamaha F150B Service Manual page 57

For the shift cutout control, fuel injection is shut off in the cylinder order #1, #4, and #3 at 2.5-second
intervals when the engine is running at 2000 r/min or more. Fuel injection to the #2 cylinder is not
shut off. When the throttle-opening angle is 30 degrees or less, fuel injection to the #3 cylinder will
begin again. When the engine speed decreases to less than 2000 r/min, fuel injection will begin
again in the cylinder order #3, #4, and #1 at 0.2-second intervals.
Concerning both overheat alert and low oil pressure alert control mode deactivate when the engine
speed is less than 1600 r/min or the throttle-opening angle is less than 7 degrees.
Block diagram
Pulser coil
TPS
Neutral switch
Engine temperature
sensor
Oil pressure sensor
Thermoswitch
Engine shut-off switch
Shift cut switch
D.E.S. switch
Crankshaft angle,
Engine speed
Throttle valve opening
Neutral position
Engine temperature
Engine
Engine oil pressure
ECM
ON/OFF
Emergency stop
Shift cut signal
ON/OFF
Electronic control system
Fuel injection
drive signal
Fuel injector #1–#4
High-pressure fuel
pump drive signal
High-pressure fuel pump
Ignition signal
Ignition coil #1 and #4
Ignition signal
Ignition coil #2 and #3
ON/OFF
Over heat,
Low oil pressure
Fuel supply
Alert buzzer
Alert indicator
10
2-14
0
1
2
3
4
5
6
7
8
9
A