Lexus ES300 (1997 year). Service manual — part 452

I00332

A/C Control Assembly

IGN

A13

16

J29

J28

F

D

J/C

B–O

IJ1

6

13

ECM

TACO

–

DIAGNOSTICS

AIR CONDITIONING SYSTEM

DI–585

737

1997 LEXUS ES300 (RM511U)

Igniter Circuit

CIRCUIT DESCRIPTION

This A/C control assembly monitors the engine speed through signals sent from the igniter. The A/C control
assembly uses these signals and compressor speed signals to detect the compressor lock condition.

WIRING DIAGRAM

INSPECTION PROCEDURE

1

Check operation of tachometer.

CHECK:
Check that the tachometer operates normally.

NG

Proceed to combination meter troubleshooting
(See page

BE–58

).

OK

2

Check harness and connector between A/C control assembly and igniter
(See page

IN–27

).

NG

Repair or replace harness or connector.

OK

Proceed to next circuit inspection shown on
matrix chart (See page

DI–535

).

DI0DP–01

EC01H–05

–

EMISSION CONTROL

EMISSION CONTROL SYSTEM

EC–1

842

1997 LEXUS ES300 (RM511U)

EMISSION CONTROL SYSTEM

PURPOSE

The emission control systems are installed to reduce the amount of CO, HC and NOx exhausted from the
engine ((3) and (4)), to prevent the atmospheric release of blow–by gas–containing HC (1) and evaporated
fuel containing HC being released from the fuel tank (2).
The function of each system is shown in these table.

System

Abbreviation

Function

(1) Positive Crankcase Ventilation

(2) Evaporative Emission Control

(3) Exhaust Gas Recirculation

(4) Three–Way Catalytic Converter

(5) Sequential Multiport Fuel injection*

PCV

EVAP

EGR

TWC

SFI

Reduces HC

Reduces evaporated HC

Reduces NOx

Reduces HC, CO and NOx

Injects a precisely timed, optimum amount of fuel for reduced

exhaust emissions

Remark: * For inspection and repair of the SFI system, refer to the SF section of this manual.

EC01I–01

S04747

VSV for Vapor
Pressure Sensor

Vapor Pressure
Sensor

EGR Valve

VSV for EVAP

Vacuum Surge Tank

VSV for EGR

VSV

Charcoal Canister

EC–2

–

EMISSION CONTROL

P

A

R

T

S

L

A

YOUT

AND SCHEMA

TIC DRA

WING

843

1997

L

EXUS ES300 (RM51

1

U

)

P

ARTS LA

YOUT AND SCHEMA

TIC DRA

WING

LOCA

TION

EC01J–05

S04775

VSV for Vapor Pressure Sensor

VSV for EGR

Vacuum Surge
Tank

EGR Valve
Position Sensor

EGR Valve

VCV

VSV for EVAP

Charcoal
Canister

Vapor Pressure
Sensor

Fuel Tank

To Air Cleaner

TWC

Heated Oxygen
Sensor
(Bank 1 Sensor 2)

Heated Oxygen Sensor
(Bank 1 Sensor 1)

Heated Oxygen Sensor
(Bank 2 Sensor 1)

–

EMISSION CONTROL

PARTS LAYOUT AND SCHEMATIC DRAWING

EC–3

844

1997 LEXUS ES300 (RM511U)

DRAWING