Lexus SC300 / Lexus SC400. Service manual - part 905

PARTS LOCATION

–

ENGINE TROUBLESHOOTING

Parts location

TR–31

WIRING DIAGRAM

TR–32

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ENGINE TROUBLESHOOTING

Wiring Diagram

–

ENGINE TROUBLESHOOTING

Wiring Diagram

TR–33

STANDARD VALUE OF ECU TERMINALS

Symbols (Terminals No.)

STD Voltage (V)

Condition

BATT (A33) – E1 (B69)

10 ~ 14

Always

IGSW (A1)

IGSW (A1)

+ B (A31) – E1 (B69)

10 ~ 14

IG switch ON

+ B (A31)

+ B1 (A32)

 E1 (B69)

10   14

IG switch ON

VC (B41)–E2 (B65)

4.0 ~ 6.0

IG switch ON

Below 1 0

IG switch ON

IDL1 (B64)

E2 (B65)

Below 1.0

IG switch ON
Main or sub throttle valve fully closed.

IDL1 (B64)
IDL2 (B63)

– E2 (B65)

10

14

IG switch ON

(

)

10 ~ 14

IG switch ON
Main or sub throttle valve fully open.

0 1

1 0

IG switch ON

VTA1 (B43)

E2 (B65)

0.1 ~ 1.0

IG switch ON
Throttle valve fully closed.

VTA1 (B43)
VTA2 (B42)

– E2 (B65)

3 0

6 0

IG switch ON

(

)

3.0 ~ 6.0

IG switch ON
Throttle valve fully open.

KS (B66) – E1 (B69)

Pulse generation

(0 and 4 ~ 6)

Idling

THA (B45) – E2 (B65)

1.0 ~ 3.0

Idling, Intake air temp. 20

°

C (68

°

F).

THW (B44) – E2 (B65)

0.1 ~ 1.0

Idling, Water temp. 80

°

C (176

°

F).

STA (B77) – E1 (B69)

6.0 or more

Cranking

#10 (B20), #20 (B19)

E01 (B80)

10 ~ 14

IG switch ON

#10 (B20), #20 (B19)
#30 (B18), #40 (B17)

– E01 (B80)

Pulse generation

Idling

IGT1 (B57), IGT2 (B56) – E1 (B69)

Pulse generation

(0 and 4 ~ 6)

Idling

Below 1.0

IG switch ON

IGF1 (B58), IGF2 (B59) – E1 (B69)

Pulse generation

(0 and 4 ~ 6)

Idling

G1 (B26), G2 (B25) – G1

 (B6)

Pulse generation

(–1.0 ~ +1.0 or higher)

Idling

NE (B27) – NE

 (B7)

Pulse generation

(–0.8 ~ +0.8 or higher)

Idling

MREL (A24) – E1 (B69)

10 ~ 14

IG switch ON

4.2 ~ 6.0

Cranking, Sudden racing (6,000 rpm)

FPC (A22) – E1 (B69)

Pulse generation

(0 and 4 ~ 6)

Idling

DI (A21) – E1 (B69)

7.5 or more

Idling

FPU (B73)

E1 (B69)

10 ~ 14

IG switch ON

FPU (B73) – E1 (B69)

Below 2.0

Restarting high temp.

PAG (B74) – E1 (B69)

10 ~ 14

Idling

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ENGINE TROUBLESHOOTING

Standard Value of ECU Terminals

TR–33