1987 TOYOTA CELICA air condition

EFJ SYSTEM - Troubleshooting with Volt/Ohmmeter (MS) FI-65
-_
No.
Tprminals Trouble Condition ._
STD Voltage
vcc
- E2
4-6V
Ignition
vs
- E2
SIW ON Measuring plate fully closed
4-6V
3 vs - E2 No voltage Measuring plate fully open
0.02 - 0.08 V
vs
- E2 Idling
2-4V
vs
- E2 3,000 rpm
0.3 - 1.0 v
0 ^,
-’ E2
r; wt.
I ’
I Air Flow Meter Air Flow Meter
# #
I- I-
= =
ECU
Air Flow Meter
I
FIl28:
I
I
I
ECU
El
Fl126!
0 There is no voltage between ECU terminals VCC or VS and E2.
(IG S/W ON)
1
0 Check that there is voltage between ECU terminal B @I) and
body ground. (IG S/W ON)
c
OK
NO
7
Refer to No. 1.
(See page FI-62)
7
Check wiring between ECU terminal El and body ground.
OK BAD
0 Check air flow meter.
(See page FI-96) Repair or replace.
,+, ,I, Check wiring between ECU and air
Try another ECU.

FI-66 EFI SYSTEM - Troubleshooting with VoltjOhrnmeter (MS)
-.
Ua. I
Terminals 1 Trouble 1 Condition
I STD Voltage
No. 10
EOI
4 No. 20 - ignition switch ON g-14v
No. 30 E02 No voltage
Battery i
T
ECU
IG S/W
‘No. IO ‘No. 20
‘No. 30
IEOI
I E02
c
+? &
=
FU.9
mb Fl291
0 There is no voltage between ECU terminal No. IO, No. 20
and/or No. 30 and EOl or E02. (IG S/W ON)
‘
J
0 Check that there is specified voltage between resistor
terminal +B and body ground. STD voltage: 9 - 14 V
Check wiring between
resistor and battery. BAD
-t Repair or replace.
I
Check that there is specified voltage between resistor terminal
@ (No. 10, No. 20 or No. 30) and body ground.
STD voltage: 9 - 14 V
I
e,+i Check resistance of magnetrc co11 rn
I
Check wiring between ECU and
iniector. I I Replace injector,

No. Terminals Trouble Condition STD Voltage
I I I I I
5 THA - E2
I No voltage ON
I Ignition switch Intake air temperature 20°C
(66°F) 1 -3v
0 ”
0 6
L -
,’ E2 (B?)
(5E2
( THA
Air Temp. Sensor
(Air Flow Meter) o El
ECU
fl275'
Air Flow Meter ’
0 There is no voltage between ECU terminals THA and E2.
(IG S/W ON)
I
0 Check that there is voltage between ECU terminal B (Bl 1 and
body ground. (IG S/W ON)
OK NO
Refer to No. 1.
(See page FI-62)
1
Check wiring between ECU terminal El and body ground.
OK
0 Check air temp. sensor.
(See page FI-96) Repair or replace.
c
BAD
OK
Replace air frow Check wiring between ECU and air
meter. temp. sensor.
OK BAD
Try another ECU.
I 1 Repair or replace. 1

EFI SYSTEM
- Troubleshooting with Voltkhmmeter (MS)
-.
No. 1
Terminals
I Trouble
I Condition ._
I STD Voltage
6 THW - E2 .No voltage Ignition switch Coolant temperature 80°C
ON (, 760F) 0.1 - 1.0 v
Water Temp. Sensor
. ECU
5 031)
THW
E2
:1
ECU I terminals THW and E2.
I
0 There is no voltage between ECU
(IG S/W ON)
I-
:.
0 Check that there is voltage between ECU terminal B (61) and
body ground. (IG S/W ON) -
1
OK NO
I
I 8 1
I
Refer to No. 1.
(See page FL62)
I
I I . -
I
Check wiring between ECU terminal El and body ground.
I BAD
Check water temp. sensor.
Repair or replace.
BAD
Replace water
temp. sensor. OK
Check wiring between ECU and water
I temp. sensor.
OK BAD
Try another ECU. 1 Repair or replace. 1

. .
No. Terminals Trouble Condition
STD Voltage
8 IGT, IGF - El No voltage Idling -- 0.7-l.OV
Ignition SW
Fusible
a AM2
Link 30A EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MS)
F12771
Y , F1277
ECU 8
&z
F12755
0 There is no voltage between ECU terminals IGT and El.
(Idling)
0 Check that there is voltage between ECU terminal IGT and
body ground. (Idling)
I
NO OK
0 Check wiring between ECU BAD Repair or
terminal El .and body ground. replace.
I OK
1 Try another ECU.
I
Check fusible link and ignition
switch. BAD
BAD
Repair or replace.
I I I
I OK I T
1 I I
Check wiring between ECU and
battery.
I BAD
c Repair or replace.
BAD
Repair or replace.
I
I 1 I

,. . .
EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MS)
FL71
No. Terminals
Trouble Condition
9 ISCl --Isc4
- El No voltage Ignition switch ON STD Voltage
9-14v
Fusible
Link
Battery EFI Main Relay
ISC Valve ECU
Fuse
EFI 15A
MAIN 1 .OY
A
=
Fl291:
B
81
’ M-REL
0 There is no voltage between ECU terminals ISCl - ISC4
and El. (10 S/W ON)
,
1
Check that there is voltage between ECU terminal B (Bl) and
@bod;TYn.. (10 S/W ON)
, Re~e!t~~o, ,. I
(See page FI-62) 1
I Check wiring between ECU terminal El and body ground.
I OK
I v
I 1
f
8 Check ISV valve.
(See page FI-108) I I Repair or replace.
I
I
I I I I 1
Check wiring between ECU and EFl
piii=-j I/
I I
I I 1 1 Try another ECU, 1 Repair or replace. 1 L
I I I

72 EFI SYSTEM ‘- Troubleshooting with Volt/Ohmmeter (MS)
40.
10 Terminals
W - El
. .
Trouble ,, Condition
No voltage _ No trouble (“CHECK engine warning
>‘Iight om and engine running STD Voltage
a-14v
. FUSE
GAUGE 7.5A
f$.; ..
w-im~~
S&INE-
Warning Light ECU
I
W
El
F12772
ECU
__
There is no voltage between ECU terminals W and El. !:, ;,:;:,p i, @
.,..I fldling)
1
,..
‘CD Check that there is voltage between ECU terminal W and
bodv around. ’ 1
_ -
I
NO OK
0 Check wiring between ECU terminal El and body
ground:..
*
OK BAD
Try another ECU.
I. Repair or replace.
: . i’ F1277
d% F12755
Check GAUGE fuse (7.5A) and “CHECK
~ ENGINE” warning light.
,. r
OK BAD
Repair or replace.
t Fuse blows again
Check wiring between ECU terminal
BAD
W and fuse. Repair or replace.

I ECU
ul +B +B
r
MS
ECU
Electronic Controlled Unit (ECU)
._
INSPECTION OF ECU
NOTE:
The EFI circuit can be checked by measuring the
resistance and voltage at the wiring connectors of the
ECU. .
1.
(MS)
PREPARATION
(See page FI-58)
2. INSPECT VOLTAGE OF ECU
Check the voltage between each terminal of the wiring
connectors.
0 Turn the ignition switch ON.
0 Measure the voltage at each terminal.
NOTE:
0 Perform all voltage measurements with the connectors
connected.
0 Verify that the battery voltage is 11 V or more when the
ignition switch is ON.
Voltage at ECU Wiring Connectors
I I I Terminals STD Voltage t Condition
I
BATT - El
IG S/W - El
10 - 14
M-REL - El
Ignition S/W ON
.
IDL - E2
VC (VCC) -. E2
VIA - E2 4-6 Throttle valve open
4-6
Ignition S/W ON
0.1 - 1.0 Throttle valve fully closed
4-5 Throttle valve fully open
4-5
Measuring plate fully closed
Ignition S/W ON
0.02 - 0.08
“‘vs Measuring plate fully open
- E2
2-4 Idling
0.3 - 1 .o 3,000 rpm
4-6
*2KS Ignition S/W ON
- E2
2-4 Cranking or running
VC - E2-
THA - E2 4-6 Ignition S/W ON
1 -3 Ignition S/W ON Intake air temperature 20°C (68°F)
THW - E2 0.1 - 1.0 Ignition S/W ON Coolant temperature 80°C (I 76°F)