throttle TOYOTA CELICA 1987 Service User Guide

I-30 .EFl SYSTE.M - Diagnosis System
DIAGNOSTIC CODES (MA)
Trouble area
I See
page Code Number of
; No. Che;;;;gine System
I
- nnrulno4 Norma’ Diagnosis
This appears when none of
the other codes area identified.
0
Ignition switch circuit
Ignition switch T
Main relay circuit
1 Main relay
1 ECU FI-41
1 Distributor circuit
r Distributor
) Starter signal circuit
b ECU
) Distributor circuit
B Distributor
B ECU IG-3
IG-3 ECU (+B) fl n Momentary interruption in 0
11
power supply to ECU.
I 0
l
Jo “NE” or “G” signal to
ICU within 2 seconds after
engine has been cranked.
Uo “NE” signal to ECU when
sngine Sp88d is above
1,000 rpm.
No “IGF” signal to ECU
i- 8 times in succession.
Ietectinn of oxygen sensor
jeterioration. E
t
C
i
P. Open or short circuit in wate
temp. sensor signal.
Open or short circuit in intake
air temp. sensor signal.
I7M-GE)
Air-flow
Meter Signal Open circuit in VC signal or
short circuit between VS and
E2 when idle contacts are
c tosed.
(7M-GTE)
Open or Short circuit in air
flow meter signal.
(‘IM-GE)
Open circuit in E2 or short
circuit between VC and VS.
(‘IM-GTE)
Open or short circuit in HAC
sensor signal
Turbocharger
Pressure ‘3
Turbocharger pressure is
abnormal. B Ignition and ignition coil
circuit
8 Igniter and ignition coil
0 ECU !I-5 1
gnition Signal
l-l 2
FI-4’
Fl-48
I!
(
!
1
,-
1
Fll608
nn n
FIl609
FI-44
d )r FI-4‘
FI-51
Open or short circuit in circuit
I Sensor Signal throttle position sensor signal. 0 Throttle position sensor
0 ECU
SHl,d , FI-4 0 Oxygen sensor circuit
l Oxygen sensor
0 ECU
0 Water temp. sensor
@muit
‘8 Water temp. sensor
l ECU
0 Intake air temp. sensor
circuit
8 Intake air temp. sensor
. ECU 3xygen Sensor
signal
Water Temp.
Sensor Signal Fll81t
Intake Air Tern
Sensor Signal 24
Fll81
0 Air flow meter circuit
0 Air flow meter
0 ECU
Fl161 0 Air flow meter Circuit
0 Air flow meter
0 ECU
0 HAC sensor circuit
l HAC sensor
l ECU
0 Turbocharger
8 Air flow meter
0 Intercooler system
0 ECU (‘IM-GE)
Air Flow
Meter Signal
(7M-GTE)
HAC Sensor
Signal Fl18
i-
,
0 Throttle position s8nsC I FIZE
n

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

EFI SYSTEM - Troubleshooting with’ Volt/Ohmmeter (MA) FI-37
Voltage at EClJ Wiring .Connectors (TIM-GE)
IO. Terminals
Condition STD Voltage
See page
BATT - El
10 - 14 FI-39
IG S/W - El
1 FI-40
M-REL - El
Ignition S/W ON 10 - 14
+B (+Bl) - El FI-41
IDL - E2 Throttle valve open 10 - 14 FI-42
vc - E2 -
4-6
2 Ignition S/W ON -
Throttle valve fully ‘closed 0.1
- 1.0 FI-43
VTA - E2
Throttle valve fully open 4-5
VC - E2 4-6
Ignition S/W ON
Measuring plate fully closed 4-5
3 Measuring plate fully open 0.02 - 0.08 FI-44
VS - E2
Idling 2-4
3,000 rpm 0.3 - 1.0
No. 10 EOI
5 No. 20 - Ignition S/W ON 9 - 14 FI-47
No. 30 E02
6 THA - E2 Ignition S/W ON Intake air temperature 20°C (68°F) 1 -3 FI-48
7 THW - E2 Ignition S/W ON Coolant temperature 80°C II 76’F) 0.1 - 1 .O
FI-49
8 STA - El Cranking
6 - 14 FI-50
9 IGF, IGT - El Idling
0.7 - 1.0 FI-5 1
11 ISCI
I&4 - El Ignition S/W ON 9-14 Fl-53
12 W - El No trouble (“CHECK ENGINE” warning light off) and
engine running 8 - 14 FI-54
13 A/C - El Air conditioning ON IO - 14 FI-55
ECU Terminals
‘~,~] E2 4
/UC W:G up +S :,:I
N:y Is’ Is’ GO Gl G2 NE IGT IGF THW OX “s, “;“riL EGR SPD FPR THA VS VC BATT IG
F1057

EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MA)
. .
Voltage at ECU Wiring Connectors (7M-GTE)
No. Terminals
Condition STD Voltage Sea page
BATT - El 10 - 14
FI-39
IG S/W - El
1
FI-40
M-REL - El Ignition S/W ON 10 - 14
+B (+Bl) - El
FI-41
*
IDL - E2 Throttle valve open 10 - 14 FI-42
VC - E2 4-6.
2 . Ignition S/W ON
Throttle valve fully closed 0.1 - 1.0 FI-43
VTA - E2
Throttle valve fully open 4-5
i
KS - Body Ignition S/W ON 4-6
FI-45
gnMid
4 Cranking or running 2-4
vc - Body
Ignition S/W ON 4-6
groulld Fl-46.
No. 10 EOl
5 No. 20 - Ignition S;W CN 9 - 14 Fl-47
No. 30 E02
6 THA - E2 Ignition S/W ON Intake air temperature 20°C (68°F) 1 -3 FI-48
7 THW - E2 Ignition S/W ON Coolant temperature 80°C (176°F) 0.1 - 1 .O FI-49
8 STA - El Cranking 6-14 FI-50
9 IGF, IGT - El Idling 0.7 - 1.0 FI-5 1
10 IGdA, IGdB - El Idling 1-3 FI-52
11 I Cl
7 9 - 14 FI-53
ISC4 - El Ignition S/W ON
12 W - El No trouble (“CHECK ENGINE” warning light off) and
engine running 8 - 14 FI-54
13 A/C - El
14 HAC - E2 Air conditioning ON 10 - 14
FI-55
540 mmHg (21.26 in.Hg. 72.0 kPa) Approx. 2.8
Ignition S/W ON FI-56
750 mmHg (29.53 in.Hg, 100.0 kPa) Approx. 3.6
ECU Terminals
I U 1 I -
I
1
‘yc ‘;c GQ Gl G2 NE IGT IGF ~Hln, OX “;’ HT r;,
EGR SPD FPR THA HAC VC ‘JAn& 0 DF
‘;’ ‘sd: VF T VTA IDL
WA ““1” K;K E2 Ll L2 L3 NC W OIL ECT FC KS +B +Bl m
TIL LP

;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.

jS EFI SYSTEM - Troubleshooting with Volt/Ohmmeter (MS)
-.
0
“B”
Fl294.
ECU
EFI SYSTEM CHECK PROCEDURE
._
PREPARATION
(a) Disconnect the connectors from the ECU.
(b) Remove the locks as shown in the illustration so that
the tester probe(s) can easily come in.
CAUTION: Pay attention to sections “A” and “B” in
the illustration which can be easily broken,
(c) Reconnect the connectors to the ECU.
’
NOTE:
0 Perform ail voltage measurements with the connectors
connected.
0 Verify that the battery voltage is 1 IV or above when
the ignition switch is at “ON”.
Using a voltmeter with high-impedance (10 kQ/V mihimum),
measure the voltage at each terminal of the wiring con-
nectors.
Terminals of ECU
rmbol Terminal Name Symbol Terminal Name
Symbol Terminal Name
EOI POWER GROUND NE DISTRIBUTOR ACPS A/C PRESSURE SWITCH
co2 POWER GROUND El COMPUTER GROUND SPD SPEEDOMETER
o. 10 INJECTOR (No. 1 and 4) VF CHECK CONNECTOR ECT ECT COMPUTER
o. 30 INJECTOR (No. 3 and 5)
GO DISTRIBUTOR ACR A/C COMPRESSOR
o. 20 INJECTOR (No. 2 and 6) TE2 CHECK CONNECTOR Ll
ECT COMPUTER
ELS DEFOGGER SWITCH
HEADLIGHT SWITCH TEl CHECK CONNECTOR L2
ECT COMPUTER
FPU VSV (FPU) KNK KNOCK SENSOR FPR FUEL PUMP RELAY
ACV VSV (A/R CONTROL) THW WATER TEMP. SENSOR L3 ECT COMPUTER
SC 1 ISC MOTOR NO. 1 COIL IDL
THROTTLE POSITION SENSOR W
WARNING LIGHT
IGT IGNITER THA AIR TEMP. SENSQR
M-REL EFI MAIN RELAY (COIL)
SC- ISC MOTOR NO. 2 COIL VTA THROlTLE POSITION SENSOR IG SiW IGNITION SWITCH 3
ISC3 ISC MOTOR NO. 3 COIL vs AIR FLOW METER Bl EFI MAIN RELAY
ISC4 ISC MOTOR NO. 4 COIL vcc AIR FLOW METER
THROTTLE POSITION SENSOR BATT BATTERY
IGF IGNITER E2
SENSOR GROUND B
EFI MAIN RELAY
G2 1 DISTRIBUTOR 1 STA 1 STARTER SWITCH
Gl 1 DISTRIBUTOR 1 NSW 1 NEUTRALSTARTSWITCH
ZU Terminals