Toyota Supra 1990 Manual page 228

FI-S4 EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (7M-GTE)
CD
• +B (+B1) - E1
ECU
Voltmeter
~~~~;I~~li~!;D
CD
There is no voltage between ECU terminals +B (+B 1) and E 1.
(lG SW ON)
CYJ
@
Check that there is voltage between ECU terminal +B (+B 1) and
body ground. (lG SW ON)
FI2911
NO
i
OK
~
Check wiring between ECU terminal E1 and body
ground.
ECU
Voltmeter
4~~~~~
~
OK
~
BAD
I
Try another ECU.
I
Repair or replace.
Check fuse, fusible links and wiring
BAD
harness.
Repair or replace.
FI2757
OK
Check EFI main relay. BAD
(See page FI-109)
Replace.
OK
Refer to M-REL - E1 trouble
section.