Lexus RX300 (MCU15). Service manual - part 43

EG

ENGINE — 1MZ-FE ENGINE

45

3. Engine Control System Diagram

Pressure
Regulator

Fuel Pump

EFI
Main
Relay

Battery

Circuit
Opening
Relay

DLC3

Combination
Meter

Air
Conditioner
ECU

Heated Oxygen Sensor
(Bank 1, Sensor 2)

Knock
Sensor

Ignition
Switch

MIL

Engine ECU

Solenoid Valves

Pulsation
Damper

TWC

Ignition Coil
with Igniter

Throttle Position Sensor

Camshaft Timing
Oil Control Valve

Air Flow
Meter

Intake Air
Temp. Sensor

Stop Light Switch

Neutral Start Switch

Water Temp.
Sensor

VSV (for EVAP)

ISC Valve

Air Fuel Ratio Sensor
(Bank 1, Sensor 1)

Electric Load Switch

Injector

Air Fuel Ratio Sensor Heater Relay

Actuator

VSV (for ACIS)

VVT Sensor

VVT Sensor

Camshaft Timing
Oil Control Valve

TWC

TWC

Air Fuel Ratio Sensor
(Bank 2, Sensor 1)

Knock
Sensor

Crankshaft
Position Sensor

187EG33

ENGINE — 1MZ-FE ENGINE

46

4. Layout of Components

Injector

Crankshaft
Position Sensor

Camshaft Timing
Oil Control Valve

VVT Sensor
(Bank 2)

Ignition Coil
with Igniter

Water Temp. Sensor

VSV (for ACIS)

Engine ECU

VSV (for EVAP)

Camshaft Timing
Oil Control Valve

Heater
Oxygen
Sensor
(Bank 1,
Sensor 2)

Air Fuel Ratio Sensor
(Bank 2, Sensor 1)

Air Fuel Ratio Sensor
(Bank 1, Sensor 1)

Knock Sensor

ISC Valve

VVT Sensor
(Bank 1)

Throttle Position Sensor

DLC3

187EG34

EG

ENGINE — 1MZ-FE ENGINE

Intake Camshaft

VVT-i Controller

VVT Sensor

Timing
Rotor

161ES42

47

5. Main Components of Engine Control System

General

The main components of the 1MZ-FE engine control system are as follows:

Component

Outline

Quantity

Air Flow Meter

Hot-Wire Type

1

Crankshaft Position Sensor (Rotor Teeth)

Pick-Up Coil Type (36 – 2)

1

VVT Sensor (Rotor Teeth)

Pick-Up Coil Type 3

1

Throttle Position Sensor

Linear Type

1

Knock Sensor

Built-In Piezoelectric Type

2

Air Fuel Ratio Sensor
(Bank 1, Sensor 1)
(Bank 2, Sensor 2)

Type with heater

2

Oxygen Sensor
(Bank 1, Sensor 2)

Type with heater

1

Injector

4-Hole Type with Air Assist

6

ISC Valve

Rotary Solenoid Type

1

VVT Sensor

A VVT sensor is mounted on the intake side of each
cylinder head.  To detect the camshaft position, a
timing rotor that is provided ont the VVT-i control-
ler is used to generate 3 pulses for every 2 revolu-
tions of the crankshaft.

ENGINE — 1MZ-FE ENGINE

157EG22

157EG23

Throttle Position Sensor

Camshaft Timing Oil Control Valve

VVT Sensor

Engine ECU

Water Temp. Sensor

Air
Flow Meter

Crankshaft Position Sensor

Crankshaft Position Sensor

Air Flow Meter

Throttle Position Sensor

Water Temp. Sensor

VVT Sensor

Target Valve Timing

Camshaft Timing Oil 
Control Valve

Correction

Actual Valve Timing

Engine ECU

Feedback

Duty Control

VVT Sensor

Camshaft Timing Oil Control Valve

48

6. VVT-i (Variable Valve Timing-intelligent) System

General

The VVT-i system is designed to control the intake camshaft within a wide range of 60

° (of crankshaft

angle) to provide a valve timing that is optimally suited to the engine condition, thus realizing improved
torque in all the speed ranges and fuel economy, and reduce exhaust emissions.