check engine light TOYOTA CELICA 1987 Service User Guide

EFI SYSTEM - Diagnosis System FI-29
MS EFI 15iA
LHD
EFI 15A
EFI 15A
R16C
FI26:
CANCELLING OUT DIAGNOSTIC CODE
1.
2. After repair of the trouble area, the diagnostic code
retained in memory by the ECU must be cancelled out by
removing the EFI fuse 15A for 30 seconds or more,
depending on ambient temperature (the lower the tem-
perature, the longer the fuse must be left out) with the
ignition switch off.
NOTE:
l Cancellation can also be done by removing the battery”
negative (-1 terminal, but in this case other memory
systems (clock etc.) will also be cancelled out.
l If the diagnostic code is not cancelled out, it will be
retained by the ECU and appear along with a new code
in event of future trouble.
l If it is necessary to work on engine components requir-
ing removal of the battery terminal, a check must first
be made to see if a diagnostic code has been recorded.
After cancellation, road test the vehicle to check that a
“normal” code is now read on the “CHECK ENGINE”
warning light.
If the same diagnostic code is still indicated, it means that
the trouble area has not been repaired thoroughly.
DIAGNOSIS INDICATION
(I) When 2 or more codes are indicated, the lowest number
(code) will appear first.
However, no other code will appear along with code No.
11.
(2) All detected diagnostic codes, except 51 and 53, will be
retained in memory by the ECU from the time of detection
until cancelled out.
(3) Once the malfunction is cleared, the “CHECK ENGINE”
warning light on the instrument panel will go out but the
diagnostic code(s) remain stored in ECU memory (except
for codes 51 and 53).

EFI SYSTEM
- Diagnosis System
FI-33
INSPECTION OF DIAGNOSIS .ClRCUlT
._
Fuse IGN
“CHECK ENGINE”
Fl291
1.
I Dose “CHECK ENGINE” warning light come
on when ignition switch is at ON?
l-l YES System Normal
Does “CHECK ENGINE” warning light come Check wiring between
on when ECU terminal W is grounded to the
YES ECU terminal El and body OK Try another
body? - ground. __c ECU
+NO
Check bulb, fuse and wiring between ECU and
ignition switch. + SAD
Repair or replace
Does “CHECK ENGINE” warning light go off
when the engine is started? YES
. System Normal
NO
Check wiring between ECU and
“CHECK ENGINE” warning light.
1 OK
Is there diagnostic code output when check
connector terminals T(MA) or TEl (MS) and
El are short circuited? t
Check wiring between ECU terminal T and check
NO connector terminal T(MA) or TEl (MS), and ECU
* terminal El and check connector terminal El.
I I
I I
YES
Does “CHECK ENGINE” warning light go out NO
after repair according to malfunction code? ) Further repair required.
&
System OK Cancel out diagnostic code.

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

EFI SYSTEM - Troub!eshoo$ng with Volt/Ohmmeter (MA)
. .
JO. Terminals
12 W - El Trouble
No voltage Condition
Nq @uble, (“CHECK” engine warning
light off) and engine running STD Voltage
s-14v
FUSE
GAUGE 7.5A
i
f “CHECK ENGINE”
Wahiing Light
Combination Mete W
El
FlO7
Joltmeter
EL v “_
Fl1251
1
Voltmeter
FH25C
. .
~0 There is no voltage between ECU terminals W and El.
(Idlin$
,
.
I 0
Check that there is voltage between ECU terminal W and
I
hod
Q;
0 Check wiring between ECU terminal El and body
Check GAUGE fuse (7.5A) and “CHECK
ENGINE” warning light.
I I
I Repair or replace.
I
1
Check wiring between ECU terminal BAD
*
W and fuse. Repair or replace.
I I
1 I

EFI SYSTEM - Ttpbleshooting with Volt/Ohmmeter (MS)
FL59
IO.
I Terminals
BATT - El
IG S/W - El
M-REL - El
2P-
I UTA - E2
3
US - E2
THA - E2
THW - E2
.B / IGF, IGT - El
9 ISCI
lSC4 - El
10
I W - El
ECU Terminals
Voltage at ECU Wiring Connectors
Condition STD Voltage ’
10 - 14
ignition S/W ON
10 - 14
Throttle valve open 10 - 14
4-6
Ignition S/W ON .
Throttle valve fully closed 0.1 - 1.0
Throttle valve fully open
4-5
4-6
Ignition S/W ON Measuring plate fully closed
4-5
Measuring plate fully open
0.02 - 0.08
Idling 2-4
3,000 rpm 0.3 - 1 .o
Ignition S/W ON 9
- 14 FI-66
Ignition S/W ON Intake air temperature 20°C (68°F) 1
-3
Ignition S/W ON
Coolant temperature 80°C (176°F) 0.1 - 1.0
Cranking
6 - 14
Idling 0.7 - 1.0
Ignition S/W ON
9 - 14
No trouble (“CHECK-ENGINE” warning light off) and
engine running 8 - 14 See page
FI-60
FI-6 1
FI-62
FI-63
FI-64
Fl-65
Fl-6.7
FI-68
FI-69
Fl-70
FI-7 1
Fl;72

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.

FI-126 EFI SYSTEM - Electronic Control &stem
Voltage at ECU W.jring Connectors (Cont’d)
.:. .I, ,,
Termlnals
Nov
10 EOI
No. 20 -
No. 30
E2
STD Voltage
6 L ,4-,: Condition
Ignition S/W ON
STA - El
ISCI
I -El
ISC4
,, : :
IGF, IGT - .E-1
*‘IGdA, lGd8 - El
:
‘2HAC - E2 6 - 14
9 - 14
-
I, .., ,i,
o .,.- i.;&& ,; ::
:,, ;;:3%
. . 1
Approx: 2.8
- Ignition S/w ON
Approlr. -3.6 L Cranking
,
Ignition S/W ON
Idling
Idling
540 mm Hg (21.26 in.Hg, 72.0 kPa)
750 mm Hg (I 29.53 in.Hg, 100.0 kPa)
W - El ‘: :g L ;I 4
: No trouble (“CHECK ENGINE” warning light off) and
engine running.
1
*3A/C - El .,. . :.llC 1~14 Air conditioning ON
>-
T - El 4A.6
Check connector T(TE1) - El not short
Ignition S/W ON
0 Check connector TfTEl) - El short
*3NSW (A/T) - El
*3N/C Uvl/TI -
El 0
Shift position P or N range
Ignition S/W ON
IO-14 Ex. P or N range
0: Clutch pedal not depressed
- Ignition S/W ON .
IO-14 Clutch pedal depressed
..-
I 1044 1 1 Defogger S/W OFF
I
“3DFG - El
“3LP - El 0
10 - 14
j) ‘. Ignition S/W ON
Defogger S/W ON
Headlight S/W OFF
Headlight S/W ON
*I 7M-GE only
*2 7M-GTE only
*3 MA only

ENGINE MECHANICAL. - Engine Tune-up
EM-?1 7.
INS’PECTIOlil ‘AhiD ADJUSTMENT O:F .-
IGNITION TIMING
1. VriARiiA. UP ENGINE.
Allow the engine to. reach normal operating temperature.
2.
CbNNECT TACHOMETER AND TIMING LIGHT TO
ENGINE
Connect the tachometer positive terminal to the check
connector terminal IG 0 .
CHECK CONNECTOR LOCATION: .,
s See pages FI-110, 111
CAUTION:
l Never allow the tachometer terminal to touch
ground as it could result in damage to the igniter
and/or ignition coil.
, 4% 3.
EC21 18
s As some tachometers are not compatible with this
ignition system, we recommend that you confirm
the compatibility of your unit before using.
NOTE (7M-GTE): Connect the timing light pickup to t
No.6 cylinder high-tension cord.
CHECK IGNITION TIMING
(a) Using a service wire, short terminals T(MA) or
TEI (MS) and El of the check connector.
CHEC,K CCNNECTOR LOCATION.:
See pages FI- 1’10, 111
(b) Check the idle. speed.
Idle speed: /-
7M-GE w/ TWC 700 rpm
w/o TWC 800 rpm
7M-GTE 800 rpm
(c) Using a timing light, check the ignition timing.
Ignition timing: IO” BTDC @ idle
[w/ short-circuited T (TEl) and El
and Transmission in “N” range]
c,
If necessary, loosen the distributor (7M-GE) or cam posz-’
tion sensor (7M-GTE) bolt and turn the distributor (cam
position sensor) to align the marks. Recheck the timing
- after tightening the distributor (cam position sensor).
Torque: 140 kg-cm (10 ft-lb, 14 N-m)
(cl) Unshort the check connector.

. .
EM-18 ENGINE MECHANICAL - Engine Tune-up
4. FURTHER CHECK IGNITION TIMING
Check that the ignition timing advances.
Ignition timing:
7M-GE ._ 10 -‘.13” BTDC @ idle
7M-GTE More than 12” BTDC @ idle
DISCONNECT TACHOMETER AND TIMING LIGHT
FROM ENGJNE