sensor TOYOTA CELICA 1987 Service Owner's Manual

EFI SYSTEM
- Diagnosis System
FI-31
DIAGNOSTIC CODES (MA) (Cont’d) __
:odc
No. Number of
Check engine
blinks Diagnosis System See
page
FL50 Trouble area
l Vehicle speed sensor
circuit
l Vehicle speed sensor
. ECU ’
I
l Ignition switch circuit
l Ignition switch
l ECU
l Knock sensor circuit
l Knock sensor
l ECU
. ECU
l A/C switch circuit
l A/C switch ‘“q
l A/C am&fire
l Neutral start switch
circuit ’
l Neutral start switch
0 Throttle position sensor
circuit
l Throttle position sensor
l ECU Vehicle Speed
Sensor Signal
Starter Signal No “SPD” signal for 5
seconds when engine speed
is between 2,500 rpm and
4,500 rpm and coolant temp.
is below 80°C (176’F) except
when racing the engine.
No “STA” signal to ECU until
engine speed reaches 800
rpm with vehicle not moving.
Knock Sensor
Signal Open or short circuit in knock
sensor signal. 42
FI161
FHBl
Fl181
FIlei
52
Knock control in ECU faulty. Knock Control
signal in ECU
No “IDL” signal, “NSW”
signal or “A/C” signal to
ECU, with check terminals
El and T shorted. Switch Signal
‘1 WI TWC vehicles only
‘2 7M-GTE only
“3 Abnormalities in the air flow meter may also be detected.
DIAGNOSTIC CODES (MS)
Number of
Check engine
System
blinks
m Normal
fl1604
nn ECU (B) Diagnosis
This appears when none of
the other codes are identified.
Momentary interruption in
power supply to ECU. Trouble area See
page
l Ignition switch circuit
l Ignition switch
l Main relay circuit
l Main relay
l ECU FI-62
l Distributor circuit
0 Distributor
l Starter signal circuit
. ECU IG-3
l Distributor circuit
l Distributor
. ECU IG-3
l Igniter and ignition coil 11
FI1605
n nn RPM Signal No “NE” or “G” signal to
ECU within 2 seconds after
engine has been cranked.
FHBOB
nnnn, RPM Signal No “NE” signal to ECU when
engine speed is above
Fl1807 1,000 rpm. 12
-
13
-
14
-LJUlJUL 1 Ignition Signal 1 * No. “IGF” signal to ECU
6 - 8 times in succession. circuit
0 Igniter and ignition coil
. ECU
.t Fl-70

FI-32 EFI SYSTEM - Diagnosis System
1 ode -
: Number of See
Check engine System Diagnosis Trouble area
paw
blinks
0 Water temp. sensor
. .
clrcult m n FI-68
0 Water temp. sensor
0 ECU _
FllBlO 0 Intake air temp. sensor
r
JUMJJJL Intake Air Temp. Open or short circuit in intake circuit
FI-67
Sensor Signal air temp. sensor signal. 0 intake air temp. sensor
. ECU
fll611
Open circuit in VC signal or
0 Air flow meter circuit
JJJJ n f
‘. ‘( <;
closed.
F11612 .
i Air flow meter circuit
DIAGNOSTIC CODES (MS) (Cont’d)
4-65
32
Fl1613 I I
I 0 Throttle position sensor
Open or short circuit in circuit
41 throttle position sensor signal.
! 0 Throttle position sensor
. ECU
Fl1614
No “SPD” signal for 5
seconds when engine speed
0 Vehicle speed sensor
42 nnnruvl
is below 80°C (176°F) except
when racing the engine.
fl16151
I
No “STA” sianal to ECU until 0 Ignition switch circuit
43
i m Starter Signal /~~n~i,‘,pee~;~ct-;~~~ng : ;;;on switch FI-6!
FM
FM
? -. Fl1616 .^
0 Knock sensor circuit
52
.I JjJJMJjn Eyn$ Sensor ~~n~op:~~ circuit in knock : :gk sensor
53
I F11616
w6,9 Kn$c~i~“,“,‘;“’ Knock control in ECU faulty. l ECU
0 A/C compressor relay
A/C Com-
Open or short circuit in circuit
pressor
Relay Signal A/C compressor relay signal. a A/C compressor relay
. ECU
f12611
0 A/C switch circuit Z
51
No “IDL” signal, “NSW” 0 A/C switch
0 A/C amplifire l Neutral start switch
circuit
0 Neutral start switch
0 Throttle position sensor
circuit
I F11617
0 Throttle position Sensor
. ECU

EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MA)
FI-35
. .
EFI SYSTEM CHECK PROCEDURE
NOTE:
l Perform all voltage measurements with the connectors
connected.
0 Verify that the battery voltage is 11V or above when
the ignition switch is at “ON”.
Using a voltmeter with high-impedance (IO kQ/V
minimum), measure the voltage at each terminal of the
wiring connectors.
I ) ECU +B
Terminals of ECU (7M-GE)
Symbol ) Terminal Name
E01 POWER GROUND
E02 POWER GROUND
No. 10 INJECTOR (No. 1 and 4)
No. 20 INJECTOR (No. 2 and 6)
STA STARTER SWITCH
No. 30 INJECTOR (No. 3 and 5)
STJ COLD START INJECTOR
El COMPUTER GROUND
NSW NEUTRAL START SWITCH (A/T)
N/C *CLUTCH SWITCH (M/T) 1 Symbol) Terminal Name
T CHECK CONNECTOR
G2 DISTRIBUTOR
VTA THROTTLE POSITION SENSOR
NE DISTRIBUTOR
IDL THROTTLE POSITION SENSOR
IGT IGNITER
IGF IGNITER
THW WATER TEMP. SENSOR Symbol
Terminal Name
L3 ECT COMPUTER
EGR
vsv (EGR)
A/C A/C MAGNET SWITCH
SPD SPEEDOMETER
W WARNING LIGHT
FPR FUEL PUMP RELAY
DFG
DEFOGGER RELAY
THA
AIR TEMP. SENSOR
ECT
ECT COMPUTER
vs AIR FLOW METER
KNK KNOCK SENSOR LP HEADLIGHT RELAY
ISC 1 ISC MOTOR NO. 1 COIL ox OXYGEN SENSOR vc THROTTLE POSITION SENSOR
AIR FLOW METER
ISC 3 ISC MOTOR NO. 3 COIL E2 SENSOR GROUND
ISC 2 ISC MOTOR NO. 2 COIL VSV 1 VSV (AIR CONTROL)
BATT BATTERY
ISC 4 ISC MOTOR NO. 4 COIL Ll ECT COMPUTER +B EFI MAIN RELAY
GQ DISTRIBUTOR VSVP VSV (FPU) IG S/W IGNITION SWITCH
VF CHECK CONNECTOR
Gl DISTRIBUTOR
ECU Terminals 1 L2 ECT COMPUTER
+Bl EFI MAIN RELAY
1 M-REL EFI MAIN RELAY (COIL)
*For cruise control
F10574

FI-36 EFI SYSTEM - Troubleshooting with VoltjOhmmeter (MA)
Terminals of ECU. (7M;GTE)
Symbol Terminal Name Symbol Terminal Name Symbol Terminal Name
EOI POWER GROUND G2 CAM POSITION SENSOR A/C A/C MAGNETIC SWITCH
E02 POWER GROUND VTA
THROTTLE POSITION SENSOR SPD SPEEDOMETER
No, 10 INJECTOR (No. 1 and 4)
NE CAM POSITION SENSOR W
WARNING LIGHT
No. 20 INJECTOR (No. 2 and 6) IDL
THROTTLE POSITION SENSOR FPR FUEL PUMP RELAY
STA STARTER SWITCH IGT IGNITER OIL OIL PRESSURE SWITCH
No. 30 INJECTOR (No. 3 and 5) IGdA IGNITER THA AIR TEMP. SENSOR
STJ COLD START INJECTOR
IGF IGNITER ECT ECT COMPUTER
rEl COMPUTER GROUND KNKl KNOCK SENSOR
t HAC 1 tl
NSW
NEUTRAL START SWITCH (A/T) THW WATER TEMP. S
N/C ‘CLUTCH SWITCH (M/T) KNK2 KNOCK SENSOR 1 vc ) THROTTLE
AIR
FLOW I
LTITUDE COMPENSATION
, .xNSOR
ENSOR 1 FC 1 CIRCUITOPENING RELAY I
IGdB IGNITER ox OXYGEN SENSOR KS AIR FLOW METER
ISC 1 ISC MOTOR NO. 1 COIL E2 SENSOR GROUND BATT BATTERY
r
ISC 3 ISC MOTOR NO. 3 COIL
vsv VSV (FPU) +B EFI MAIN RELAY
ISC 2 ISC MOTOR NO. 2 COIL Ll ECT COMPUTER IG S/W IGNITION SWITCH
ISC 4 ISC MOTOR NO. 4 COIL HT OXYGEN SENSOR +Bl EFI MAIN RELAY
GO CAM POSITION SENSOR L2 ECT COMPUTER TIL
TURBO INDICATOR
VF CHECK CONNECTOR M-REL
EFI MAIN RELAY (COIL) DFG DEFOGGER RELAY
Gl CAM POSITION SENSOR L3 ECT COMPUTER LP HEADLIGHT RELAY
T CHECK CONNECTOR
EGR VSV (EGR)
ECU Terminals
E2 Ll L2 L3 A/C W OIL ECT FC KS +B +Bl
+
F10574 Fll 99:
*For cruise control

;I-42 EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MA)
NO, Terminals
IDL - E2 Trouble Condition ..
Throttle valve open STD Voltage
10 - 14 v
2 }-I No voltage / s$t;;N -
Throttle valve fully closed o.‘: I;,; v
I VTA - E2
I I Throttle valve fully c
I I I I
Throttle Position Sensor
Ei
I IDL
VTA
VC
El 4-5v
I
Voltmeter
R102,
FlO31
l IDL - E2
0 There is no voltage between ECU terminals IDL and E2.
(IO S/W ON) (Throttle valve open)
c
I
0 Check that there is voltage between ECU terminal +B (+Bl)
and body ground. (IO S/W ON)
c h
, 1
1 OK ’
1 1 Check wiring between ECU terminal El and body ground.1
t
Refer to No. 1.
(See page FI-41)
I
BAD
7
- Replace or repair.
1
b
OK
,
1
I@ Check throttle position sensor. 1 BAD
1
I BAD OK
.
Check wiring between ECU and
throttle position sensor.
1

EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MA) FI-43
Voltmeter
El v:
(r:
c
cc
I ECU A VTA
Fll62f
Voltmeter
m ECU vc
l VC - E2
0 There is no voltage between ECU terminals VC and E2.
(IO
S/W ON)
1
Check that there is voltage between ECU terminal +6 (+El) and
body ground. (IO S/W ON)
OK
CD Check throttle position sensor,
(See page FI-102)
BAD
OK
I
I Repair or replace.
I 1 Check wiring between ECU and throttle
nosition sensor. I
I I I’
I I
1 OK
1 BAD
1 1
I I T
I
I Try another ECU. 1 :;;i. or replace 1
. VTA - E2
@There is no specified voltage at ECU terminals VTA and E2.
(IG S/W ON)
1
0
Check that there is voltage between ECU terminal VC and E2.
(IO S/W ON)
1 OK
t 1
7 I I
I
Check wiring between ECU and
BAD
throttle position sensor.
H Repair or replace.
I
1
J I I
I OK
I Try another ECU.

FI-48 EFI SYSTEM - Troubleshooting with Volt/Ohmmeter.(MA)
I
7M-GE
@
.-
Air Flow Meter
UO.
6 Terminals
THA - E2 Trouble Condition ._ ST0 Voltage
No voltage IG S/W ON Intake air temperature 20°C (68°F) 1 -3v
IM-GE
1 I Air Temp. Sensor
(Air Flow Meter) ECU
+B
(+Bl)
E2
THA
lE1 7M-GTE
ir Temp. Sensor
iir Flow Meter)
1
I THA
E2
I
ECU
CB
-i-B11
l-HA
0 There is no voltage between ECU terminals THA and E2.
(IG S/W ON)
1
Fl1636
‘M-GTE
Ohmmeter Air Flow Meter
I/ 1” THA / Check that there is voltage between ECU terminal +B (+Bl) and
body ground. (IO S/W ON)
I
OK NO
Refer to No. 1.
(See page FI-4 I)
Check wiring between ECU terminal El and body ground.
OK
t
I I I
0 Check air temp. sensor.
(See pages FI-96, 98)
L * 1 Repair or replace. ]
I
I
BAD OK
Replace air flow Check wiring between ECU and air
meter. temp. sensor.
L k
OK
Try another ECU. Repair or replace.

EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MA) Fl-49
-.
No.
Terminals Trouble
Condition
STD Voltage
7 THW - E2 No voltage ignition switch
Coolant temperature 80°C
ON (1780~) o-q - l-0 V
ECU
Water Temp. Sensor
. iB (+Bll
THW
E2
El
Jf /
Voltmeter
n F1031:
1
0 There is no voltage between ECU terminals THW and E2.
(IO S/W ON)
1 i
CD Check that there is voltage between ECU terminal +B (+Bl) and
body ground. (IG S/W ON)
1
OK
NO
Refer to No. 1.
(See page FI-41)
Check wiring between ECU terminal El and body ground.
OK
, 1
0 Check water temp. sensor.
(See page FI-1 161
I I
Try another ECU. OK
Check wiring between ECU and water
temp. sensor.
OK BAD
Repair or replace.

EFI SYSTEM -. Troubleshooting with Volt/Ohmmeter (MA) FI-51
I-
i’
No. Terminals
Trouble Condition
STD Voltage
9 IGT, IGF - El
No voltage Idling
0.7 - 1.0 v
ECU
Fusible
Link
Battery Fusible Link Ignition Switch
AM2 30A
Tachometer
MAIN 2.OL
IGF
IGT
El
Voltmeter
EL It’-
Ohmmeter
0 There is no voltage between ECU terminals IGT and El.
(Idling)
I
I
0 Check that there is voltage between ECU terminal IGT and
body ground. (Idling)
I NO I OK
1
0 Check wiring between ECU BAD Repair or
terminal El and body ground. replace.
I
Check fusible links and ignition
switch. Repair or replace.
I
1 I I I
1 OK
Check distributor or cam position
BAD
sensor. (See pages IG- 11, 18) - Repair or replace.
I
1 OK
Check wiring between ECU and
battery. BAD
*-Repair or replace.
I
I I L I
1 OK
Repair or replace.

FI-52 EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MA)
No.
‘10 Terminals
lGdA - El
IGdS Trouble
No voltage
._
Condition
idling STD Voltage /
1 -3V
‘7M-GTE only
Fusible
Link
AM2
30A Ignition
Switch
AM241G2
T
Battery 1
L
I
= TO
7 Tachometer
niter
L
I
=
ECU
IGdA
IGdB
El
Joltmeter
F1195
-l
0
There is no voltage between ECU terminals IGdA or IGdB and
El. (Idlinal
0 Check that there is voltage between ECU terminal IGdA or
IGdB and body ground. (Idling)
,
I
I , NO 1 9
0
Check wiring between ECU BAD Repair or
L
terminal El and body ground. replace.
OK
Try another ECU.
Check fusible links and ignition BAD
switch. - Repair or replace.
c
I
I 1
I r 1 Check cam position sensor.
(See page IG-18)
I Repair or replace.
I
Check wiring between ECU and
batter-v. Repair or replace.
I 1 J
I
BAD
I I I