Technical Features And Description; Electronic Control System - Yamaha F150B Service Manual

TECH
FEA

Electronic control system

F150B uses engine ECM to control the fuel injection amount and the ignition timing, and to reduce
the engine speed in case of over heating and low oil pressure. Dependable startability, stable trolling
speed, sharp acceleration, high output power, improved fuel economy, and low exhaust emissions
are assured by controlling the air-fuel ratio and ignition timing appropriately depending on various
engine operating conditions.
Self-diagnosis function is incorporated in F150B. Malfunctions can be detected quickly by running
the optional diagnostic software to be installed in a personal computer.
F150B has fail-safe functions. In the event of a failure related to each sensor and actuator, the fail-
safe function works to continue the control using the reference values set by engine ECM, or stop
the engine. It also gives warning to the boat operator of the occurrence of failure by lighting the alert
indicator, or activating the alert buzzer.
Electronic control module system diagram
Vapor
Battery
2-1

Technical features and description

High-
pressure
fuel pump
Vapor
separator
Ignition coil
Fuel injector
Idle Speed Control
Fuel Control
Ignition Control
Engine
ECM
Tachometer and
Trim meter
Filter
Filter
Fuel pumps
ISC valve
TPS
Pulser coil
Air pressure sensor
Oil pressure sensor
Engine temperature sensor
Air temperature sensor
Thermoswitch
Shift cut switch
Neutral switch
Hour meter
Canister
Fuel
Water
detection
switch
Air