FI/EFI System, page 65

EFI SYSTEM — Troubleshooting with Volt/Ohmmeter (7M-GTE)     FI-65

No.    Terminals    Trouble    Condition    STD Voltage
10    ISC1 - ISC4 - E1    No voltage    Ignition switch ON    9 - 14 V

EFI Main Relay    ISC Valve    ECU

Fuse
EFI 15A

AM2 2.0A

Fusible
Link

MAIN 2.0L

Battery

ISC1
ISC2
ISC3
ISC4

J8
J81
M-REL

E1

FI2659

ISC1 ISC2 ISC3 ISC4    ①
ECU

Voltmeter

FI1609

②

Voltmeter

J81
E1

FI2757

③

J8/B2  S2
S1
S3

J81
Battery

FI1643

① There is no voltage between ECU terminals ISC1 ~ ISC4 and E1.
(IG SW ON)

② Check that there is voltage between ECU terminal J8 (J81) and
body ground. (IG SW ON)

OK    NO

Refer to No. 1.
(See page FI-54)

Check wiring between ECU terminal E1 and body ground.

OK    BAD

Repair or replace.

③ Check ISV valve.
(See page FI-106)

BAD    OK

Replace ISC
valve.

Check wiring between ECU and EFI
main relay.

OK    BAD

Try another ECU.    Repair or replace.