Electronic Controlled Unit - Toyota Celica Supra 1986 Service And Repair Manual

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EFI SYSTEM - Elect ronic Control System
Electronic Controlled Unit (ECU)
INSPECTION OF ECU
1. MEASURE VOLTAGE OF ECU
Fl-75
NOTE: The EFI circuit can be checked by measuring
the resistance and voltage at the wiring connectors of
the ECU.
Check the voltages at the wiring connectors.
• Remove the glove box.
• Turn on the ignition switch .
• Measure the voltage at each terminal.
NOTE: 1. Perform all voltage measurements with the connectors connected.
2. Verify that the battery voltage is 11V or above when the ignition switch is ON.
Connectors of ECU
Symbol Termin.ol Ne.me Symbol Terminal Name Symbol Terminal Ne:rn8
E<>o ENGINE GROUND
GE>
ENGINE REVOLUTION SENSOR A/C AJC MAGNET SWITCH
E<>•
ENGINE GROUND VF CHECK CONNECTOR SPO SPEEDOMETER
No. 10
INJECTOR
G
ENGINE REVOLUTION SENSOR
w
WARNING LIGHT
No.
20 INJECTOR T CHECK CONNECTOR THA AIR TEMP. SENSOR
STA STARTER SWITCH VTA THROTTLE SWITCH Vs AIR FLOW METER
IGt IGNITER
No
ENGINE REVOLUTION SENSOR Vc AIR FLOW METER
EGR EGR VSV
IOL
THROTTLE SWITCH
BAT
BATTERY +8
Eo ENGINE GROUND KNK KNOCK SENSOR IG S/W IGNITION SWITCH
NEUTRAL STAAT SWITCH IAITI
IGf IGNITER + 8
MAIN RELAY
N/C
CLUTCH SWITCH IM/TI
Ox
OXYGEN SENSOR
TCO
ECT COMPUTER
ISCo ISC MOTOR NO. 1 COIL THW WA TEA TEMP. SENSOR Oil OIL PRESSURE SWITCH
ISC> ISC MOTOR NO. 2 COlt
E>
SENSOR EARTH L o ECT COMPUTER
ISC>
ISC MOTOR NO. 3 COIL Eo ENGINE GROUND L> ECT COMPUTER
ISC•
ISC MOTOR NO. 4 COIL M -REL MAIN RELAY COIL
L3 ECT COMPUTER
e.,
,1;
STA
EGR
NIC
ISC ISC
GG
G
...
IGf
HW
,,
,,
,,
M·
SPO
lH.A
Vt Vo BAT
~
t
2
REL ...
~·
IGt
E,
o sc
ISC
VF
T
VTA
IDL
KHK
Ox
E,
'·
Eo
TC:O AIC
w
OIL
•e ••
3
4
....
,