Lexus SC300 / Lexus SC400. Manual - part 499

SERVICE DATA (Cont’d)

Water temp.
sensor

Resistance

at –20

°

C (–4

°

F)

at 0

°

C (32

°

F)

at 20

°

C (68

°

F)

at 40

°

C (104

°

F)

at 60

°

C (140

°

F)

at 80

°

C (176

°

F)

10 – 20 k

4 – 7 k

2 – 7 k

0.9 – 1.3 k

0.4 – 0.7 k

0.2 – 0.4 k

EGR gas
temp.
sensor

Resistance

at 50

°

C (112

°

F)

at 100

°

C (212

°

F)

at 150

°

C (302

°

F)

69 – 89 k

12 – 15 k

2 – 4 k

Main oxygen
sensor

Heater coil resistance

5.1 – 6.3 

Sub–oxygen
sensor

Heater coil resistance

5.1 – 6.3 

ECU

HINT:

Perform all voltage and resistance measurements with the ECU connected.

Verify that the battery voltage in 11 V or above with the ignition switch is ON.

Voltage

Terminals

Condition

STD voltage (V)

BATT – E1

–

10 – 14

IGSW

+B – E1

+B1

IG SW ON

10 – 14

VC – E2

–

4.0 – 6.0

IDL1

E2

Throttle (or sub–throttle) valve fully closed

1 or less

IDL1
IDL2

– E2

IG SW ON

Throttle (or sub–throttle) valve fully open

10 – 14

VTA1

E2

Throttle (or sub–throttle) valve fully closed

0.1 or less

VTA1

VTA 2

– E2

Throttle (or sub–throttle) valve fully open

3.0 – 6.0

KS – E1

Idling

Pulse generation

THA – E2
THW – E2

Idling

Intake air temp. 20

°

C (68

°

F)

1.0 – 3.0

THW – E2

Idling

Engine coolant temp. 80

°

C (176

°

F)

0.1 – 1.0

STA – E1

Cranking

6.0 or more

#10
#20

E01

IG SW ON

10 – 14

#20
#30
#40

–

E01
E02

Idling

Pulse generation

IGT1
IGT2

– E1

Idling

Pulse generation

FI–138

EFI SYSTEM   –   Service Specifications

SERVICE DATA (Cont’d)

ECU (cont’d)

Voltage (cont’d)

Terminals

Condition

STD voltage (V)

IGF1

E1

IG SW ON

1.0 or less

IGF1
IGF2

– E1

Idling

Pulse generation

G1
G2

G1 (–)
G2 (–)

–

Idling

Pulse generation

NE – NE (+)

Idling

Pulse generation

M–REL – E1

IG SW ON

10 – 14

FPC

E1

Cracking, Sudden racing (6,000 rpm)

4.2 – 6.0

FPC – E1

Idling

Pulse generation

DI – E1

Idling

7.5 or more

FPU

E1

IG SW ON

10 – 14

FPU – E1

Restarting high temp.

2.0 or less

PAG – E1

IG SW ON

10 – 14

ISC1
ISC2
ISC3
ISC4

– E1

IG SW ON

10 – 14

VF1
VF2

– E1

Maintain engine speed at 2,500 rpm for 120 seconds
after warming up then return to idling.

1.0 – 4.0

OXR1

OXL1

– E1

Maintain engine speed at 2,500 rpm for 120 seconds
after warming up

Pulse generation

(0 – 1.0)

HTR1
HTR2

E01

IG SW ON

10 – 14

HTR2

HTL1
HTL2

–

E01
E02

Idling

2.0 or less

EGR1
EGR2
EGR3
EGR4

– E1

IG SW ON

10 – 14

EGR – E1

Idling

10 – 14

KNK1
KNK2

– E1

Idling

Pulse generation

NSW

E1

IG SW ON

Shift position ”P” or ”N” range

1.0 or less

NSW – E1

IG SW ON

Ex. shift position ”P” or ”N” range

10 – 14

FI–139

EFI SYSTEM   –   Service Specifications

SERVICE DATA (Cont’d)

ECU (cont’d)

Voltage (cont’d)

Terminals

Condition

STD voltage (V)

SPD – E1

IG SW ON

Rotate driving wheel slowly.

4 or more

TE1
TE2

– E1

IG SW ON

10 – 14

W

E1

IG SW ON

2.0 or less

W – E1

Idling

10 – 14

AD – E1

Idling

10 – 14

OD1 – E1

IG SW ON

4.0 – 6.0

A/C

E1

A/C SW ON (at idling)

2.0 or less

A/C – E1

A/C SW OFF

10 – 14

ACMG

E1

A/C SW ON (at idling)

2.0 or less

ACMG – E1

A/C SW OFF

10 – 14

TR – E1

IG SW ON

10 – 14

VT01

E2

IG SW ON

Throttle (or sub–throttle) valve fully closed

1.0 or less

VT01
VT02

– E2

IG SW ON

IG SW ON Throttle (or sub–throttle) valve fully open

3.0 – 5.5

NE0 – E1

IG SW ON

4.0 – 6.0

Resistance of wiring connector side

Terminals

Condition

STD voltage (

)

–

#10
#20
#30
#40

+B
+B1

–

13.2 – 14.2

–

STJ

+B
+B1

–

2 – 4

–

ISC1
ISC2
ISC3
ISC4

+B
+B1

–

10 – 30

–

FPU

+B
+B1

–

37 – 44

–

EGR1
EGR2
EGR3
EGR4

+B
+B1

–

19.9 – 23.4

–

EGR

+B
+B1

–

33 – 39

FI–140

EFI SYSTEM   –   Service Specifications

SERVICE DATA (Cont’d)

ECU (cont’d)

Resistance of wiring connector side (cont’d)

Terminals

Condition

STD voltage (

)

–

HTR1
HTR2

HTL1
HTL2

+B
+B1

–

5.1 – 6.3

–

PAG

+B
+B1

–

30 – 34

–

IDL1

+B

Throttle valve fully open

Infinity

–

IDL1
IDL2

+B
+B1

Throttle valve fully closed

2,300 or less

–

VTA1

E2

Throttle valve fully open

3,300 – 10,000

–

VTA1
VTA2

E2

Throttle valve fully closed

200 – 800

VC – E2

–

4,000 – 9,000

THS – E2

Intake air temp, 20

°

C (68

°

F)

2,000 – 3,000

THW – E2

Coolant temp. 80

°

C (176

°

F)

200 – 400

THG – E2

EGR gas temp. 50

°

C (112

°

F)

69,400 – 88,500

G1
G2

G1 (–)
G2 (–)

–

Cam position sensor – 10 – +40

°

C (14 – 104

°

F)

835 – 1,350

NE – NE (–)

engine speed sensor – 10 – +40

°

C (14 – 104

°

F)

835 – 1,350

Fuel cut rpm

w/ Vehicle speed 0 km/h and coolant temp. 80

°

C (176

°

F)

Fuel cut rpm
Fuel return rpm

1,800 rpm
1,400 rpm

FI–141

EFI SYSTEM   –   Service Specifications