Lexus SC300 / Lexus SC400. Manual - part 332

5. INSPECT 

WATER 

TEMPERATURE 

SENSOR

Using an ohmmeter, measure the resistance between the ter-
minals.

Resistance: 1.48–1.58 k

 at 80

°

C (176

°

F)

If the resistance is not as specified, replace the sensor.

6. REINSTALL 

WATER 

TEMPERATURE 

SENSOR

(a)  Install a new O–ring to the water temperature sensor.
(b)  Apply soapy water to the O–ring.
(c)  Install the water temperature sensor to the radiator.

Torque: 7.4 N

⋅

m (75 kgf

⋅

cm, 65 in.

⋅

lbf)

(d)  Connect the water temperature sensor connector.

7. 

REFILL WITH ENGINE COOLANT (See page 

CO–7

)

8. 

REINSTALL ENGINE UNDER COVER

9. 

RECONNECT CABLE FROM NEGATIVE TERMINAL OF
BATTERY

(A/C High–Pressure Switch)

INSPECTION OF A/C HIGH–PRESSURE
SWITCH

1. 

DISCONNECT HIGH–PRESSURE SWITCH CONNECTOR

2. 

INSTALL MANIFOLD GAUGE SET (See AC section)

3. 

INSPECT HIGH–PRESSURE SWITCH
(a)  When the A/C switch is OFF, check that there is

continuity between terminals 2 and 3. (When the
pressure is 1,226 kPa (12.5 kgf/cm

2

, 178 psi) or lower.)

(b)  When the A/C switch and blower switch are ON, check

that there is no continuity between terminals 2 and 3.
(When the pressure is 1,520 kPa (15.5 kgf/cm

2

, 220 psi)

or higher.)

If continuity is not as specified, replace the switch.

4. 

REMOVE MANIFOLD GAUGE SET

5. 

RECONNECT HIGH–PRESSURE SWITCH CONNECTOR

(Solenoid Valve)

(See page 

CO–36

)

–

COOLIING SYSTEM

Electronically Controlled Hydraulic
Cooling Fan (Electronic Control Parts)

CO–63

SERVICE SPECIFICATIONS

SPECIFICATIONS

VSV (For EVAP) 

Resistance

30–34 

VSV (For EGR)

Resistance

33–39 

TORQUE SPECIFICATIONS

Part tightened

N m

kgf cm

ft

⋅

lbf

VSV for EGR X Intake manifold

18

185

13

EGR valve X Intake manifold

18

185

13

EGR valve X EGR Pipe

64

650

47

Catalytic converter (Front) X Exhaust manifold

62

630

46

Catalytic converter (Front) X Front Exhaust pipe

43

440

32

Front exhaust pipe X Center exhaust pipe

43

440

32

Sub–oxygen sensor X Front exhaust pipe

18

180

13

EC–20

–

EMISSION CONTROL SYSTEMS

Service Specifications

THREE–WAY CATALYST (TWC) SYSTEM

DESCRIPTION

To reduce HC, CO and NOx emissions, they are oxidized, reduced and converted to nitrogen (N2), carbon

dioxide (CO2) and water (H2O) by the catalyst.

OPERATION

EC–26

–

EMISSION CONTROL SYSTEMS

Three–Way Catalyst (TWC) System

INSPECTION OF EXHAUST PIPE
ASSEMBLY

1. 

CHECK CONNECTIONS FOR LOOSENESS OR DAMAGE

2. CHECK 

CLAMPS 

FOR 

WEAKNESS, 

CRACKS OR

DAMAGE

INSPECTION OF CATALYTIC
CONVERTERS

CHECK FOR DENTS OR DAMAGE

If any part of protector is damaged or dented to the extent that
it contacts the converter, repair or replace it.

INSPECTION OF HEAT INSULATORS

1. 

CHECK HEAT INSULATOR FOR DAMAGE

2. CHECK 

FOR 

ADEQUATE 

CLEARANCE 

BETWEEN

CATALYTIC CONVERTER AND HEAT INSULATOR

COMPONENTS FOR REPLACEMENT OF CATALYTIC CONVERTERS

–

EMISSION CONTROL SYSTEMS

Three–Way Catalyst (TWC) System

EC–27