Page 367 of 1164

SELF-DIAGNOSIS FUNCTION F
TEP
6
7
8
9
IO
11 INSPECTION
Check for correct fuel line pressure at idle
IV page F-122
Fuel line pressure:
265-314 kPa (2.7-3.2 kg/cm’, 38-46 psi)
(Vacuum hose to pressure regulator
disconnected)
Check intake air system components for air
leakage
Check for misfire of dead cylinder from Step 5
inspection
Check for injector operating sound at idle of
dead cylinder from Step 5 inspection -
Replace injector at dead cylinder from Step 5 in-
spection
CI page F-131
Check if same Code No. is present following
performing after-repair procedure
CT page F-104
Try known good ECU and check if condition
Improves
CT page F-149 Yes
No
Yes If not clogged, check fuel pump
maximum pressure
Go to Step 11
No Replace
--
Yes Repair or replace ignition system
No
Yes
No
Yes
No
T L ACTION
Go to next step
Low pressure
Check fuel line pressure while pinching
fuel return hose
~3 If fuel line pressure quickly in-
creases, check pressure regulator
v page F-129
c3 If fuel line pressure gradually in-
creases, check for clogging be-
tween fuel pump and pressure
regulator
CT page F-126
Go to next step
Go to next step
Check for battery voltage at injector
connector terminal-wire (W/R)
L3 If Yes, replace injector c7 page F-131
+ If No, check wire harness for short
or open
Go to next step
Removed injector at fault
Circuit Diagram
ATX
OXYGENSENSOR
R/L
ECU
-------------- ---
BILG
23UOFX-07
F-10'
Page 368 of 1164

SELF-DIAGNOSIS FUNCTION
:ODE No. 1 25 (SOLENOID VALVE - PRESSUREREGULATORCONTROL)-BPENGINE
r (
TEP
1
-
2
-
3 I
INSPECTION
Disconnect connector from ECU and check if
battery voltage exists at ECU terminal 2T (MTX)
3M (ATX) wire (G/O) with ignition switch ON
In same condition as Step 1, check if battery
voltage exists at solenoid valve connector
terminal-wire (G/O) ACTION
Yes Check ECU terminal connector for poor -
connection
* If OK, replace ECU CT page F-149
+
If not OK, repair or replace connector
No Go to next step
Yes Repair or replace wire (G/O)
No Go to next step
Check if solenoid valve is OK Yes Check for short or open circuit in wiring
w page F-135 from main relay (FUEL INJ relay) to
solenoid valve
No Replace solenoid valve
I I I
23UOFX-077
:ODE No. 26 (SOLENOID VALVE - PURGE CONTROL)
STEP INSPECTION
Disconnect connector from ECU and check if
battery voltage exists at ECU terminal 2X (MTX)
20 (ATX) wire harness (W/L) with ignition switch
ON Yes
No
In same condition as Step 1, check if battery
Yes
voltage exists at solenoid valve connector
terminal-wire (W/L)
No
Check if solenoid valve is OK
Yes
w page F-140
t- No
--
4 ACTION
Check ECU terminal connector for poor
connection
ti If OK, replace ECU c;p page F-149
e
If not OK, repair or replace connector
Go to next step
Repair or replace wire harness (W/L)
Go to next step
Check for short or open circuit in wiring
from main relay (FUEL INJ relay) to
Circuit Diagram
MTX
I-
FROM
BATTERY
FROM
23UOFX-07 9
F-l 02
Page 369 of 1164

SELF-DIAGNOSIS FUNCTION F
1
CODE No. 34 (ISC VALVE)
1 ACTION
Yes Check ECU terminal connector for poor
connection INSPECTION
Disconnect connector from ECU and check if
battery voltage exists at ECU terminal 2W (MTX)
3Q (ATX) wire (L/O) with ignition switch ON
c3 If OK, replace ECU
+ If not OK, repair or replace con-
nector w page F-149
No Go to next step
In same condition as Step 1, check if battery
voltage exists at ISC valve connector terminal.
wire (L/O) Yes ) Repair or replace wire (L/O)
No Go to next step
Yes Check for short or open circuit in wiring
from main relay (FUEL INJ relay) to ISC
valve
No Replace ISC valve Check ISC valve for correct resistance
w page F-i 16
Resistance: 1 l-130 [at 20°C(68”F) ]
I 23UOFX-08( I
r C :ODE No. )
41 (SOLENOID VALVE - VICSbDOHC
I
ii
T
I
INSPECTION
ACTION
Check ECU terminal connector for poor
connection
in’
I
* If OK, replace ECU w page F-149
c3 If not OK, repair or replace con-
nector
No Go to next step Disconnect connector from ECU and check if
battery voltage exists at ECU
terminal 2S (MTX)
31 (ATX) wire (B/R) with ignition switch ON
2 In same condition as Step 1, check if battery voltage exists at solenoid valve connector
terminal-wire (B/R)
Check if solenoid valve is OK
w page F-l 18 Yes Repair or replace wire (B/R)
No Go to next step
Yes Check for short or open circuit in wiring
from main relay to solenoid valve
No
Replace solenoid valve
23UOFX-081 3
Circuit Diagram
ATX
ISC VALVE
FROM
BATTERY 4
FROM
L
IGNITION d++n.D,,
SWITCH
MAIN RELAY
(FUEL INJ RELAY) S
4\ ECU
SOLENOID VALVE
i(VICS) [DOHC]
W/R ,,
\
SOLENOID VALVE ,
(PURGE CONTROL)
23UOFX-082
F-i 03
Page 400 of 1164
F PRESSURE REGULATOR CONTROL SYSTEM
PRESSURE REGULATOR CONTROL SYSTEM (BP ENGINE)
THERMOSEN
SOLENOID VALVE
(PRESSURE REGULATOR CONTROL)
(FROM DELIVERY
FUEL
(TO FUEL TANK)
Engine
BP SOHC
BP DOHC Coolant temperature
Above 90% (194*F) Operating condition
Intake air temperature
Above 50°C (122OF)
Above 58OC (136OF) Engine condition . Operating time (set)
Throttle valve fully closed
Approx. 120
or no load condition
Approx. 60
#.nr IAt-%/ 4 7
To prevent percolation of the fuel during hot restart idle, vacuum to the pressure regulator is momentarily
cut, and the fuel injection pressure is increased to slightly more than 284 kPa (2.9 kg/cm2, 41.2 psi).
F-l 34
Page 420 of 1164

CONTROL SYSTEM
Ve: Battery
arminal Input Output Connection to lest condition Correct voltage Remark
2A - - Ground (Injector) Constant ov -
28 - - Ground (Output) Constant ov -
2c - - Ground (CPU) Constant ov -
2D - - Ground (Input) Constant ov -
2E 0 Distributor Ignition switch ON
Approx. OV
(Ne-signal) or 4.5-5.5V -
Idle Approx. 2V
2F - - - - - -
2G 0 Distributor Ignition switch ON Approx. OV
(G-signal) [DOHC] or 4.5-5.5V
Idle Approx. 1.5V
2H 0 Ground (California) Constant ov
-
Main relay Ignition switch ON Va
(Canada)
21 - - - - - -
2J 0 Open Constant Approx. l-29 -
2K 0 Throttle sensor Constant 4.5-5.5v
(ATX)/Airflow meter
-
2L 0 Throttle sensor
(Power switch) Accelerator pedal released
Accelerator pedal fully depressed Approx. 4.5~5%
ov -
2M 0 Throttle sensor Accelerator pedal released
Accelerator pedal fully depressed Approx. 0.5V
Approx. 4.OV -
2N 0 Oxygen sensor Ignition switch ON ov
Idle (Cold engine) ov
Idle (After warm-up) O-l .ov -
Increasing engine speed (After warm-up) 0.5-I .ov
Deceleration o-0.4v
20 0 Airflow meter Ignition switch ON Approx. 3.8V
-
Idle Approx. 3.3V
2P 0 Intake air ther- Ambient air temperature 20% (68OF) Approx. 2.5V Built in airflow
mosensor meter
2Q 0 Water thermo- Engine coolant temperature 20% (68’F) Approx. 29
_
sensor
After warm-up Below 0.5V
2R - - - - -
- 711 ICIFX-12 voltage
_““_. ,. .I 7
1 r u-
r-i Ll r
2Y 2w 2u 2s 20 20 2M 2K 21 2G 2E 2~2 2A 1U 1s 1Q 10 lft,j ,K ,, ,G ,E ,c ,A
22 2x 2v 2T 2R 2P 2N 2L 2J 2H 2F 2D 28
IV 1T fR 1p 1N 1L 1J ,H IF ID ,B
F-l 54
Page 422 of 1164

F CONTROL SYSTEM
Ve: Battery voltage
erminal Input Output Connection to
Test condition Correct voltage Remark
2s 0 Solenoid valve
Engine speed below 5,000 rpm ov VICS: Variable In-
(VICS)
Engine speed above 5,000 rpm
VB ertia Charging
System [DOHC]
2T 0 Solenoid valve
60 [DOHC]/120 [SOHC] seconds after ov
(Pressure regula- engine started when engine coolant tem-
tor) [BP] perature above 90% (194OF) and intake
-
air temperature above 58% (136’F)
[DOHC]/50% (122OF) [SOHC]
Other condition at idle
Ve
2u
0 Injector (Nos. 1, 3) Ignition switch ON V0 *Engine Signal
idle
VB Monitor: Green
Engine speed above 2,000 rpm on de-
VB and red lamps
flash
celeration (After warm-up)
2v 0 Injector (Nos. 2, 4) Ignition switch at idle
Ve
idle
VI3
Engine speed above 2,000 rpm on de-
VB celeration (After warm-up)
2w
0 ISC valve Ignition switch ON Approx. 7V
-
Idle
Approx. QV
2x 0 Solenoid valve Ignition switch ON
VB (Purge control) -
Idle VB
2Y - - - - - -
23UOFX-1:
I r
U----l l-l
Ll I-
2y
2w 2u 2s 20 20 2M 2K 21 23 2E 2C 2.4 1U 1s 10 10 1M 1K 11 1G 1E 1~ IA
2z 2x 2’4 2T 2R 2P 2N 2L 2J 2l-i 2F 2D 28 IV 1T 1R lp IN IL 1J 1~ 1F If) 1~ -/
F-l 56
Page 428 of 1164

F CONTROL SYSTEM
VB: Battery voltage
erminal Input Output Connection to
Test condition Correct voltage Remark
28 1 0 )
1 Airflow meter Ignition switch ON Approx. 3.8V
-
2c 0 Oxygen sensor
2D 0 Fan switch Idle Approx. 3.3V
Ignition switch ON ov
Idle (Cold engine)
ov
Idle (After warm-up) O-l .ov -
increasing engine speed (After warm-up) 0.5-I .ov
Deceleration o-0.4v
Fan operating (Engine coolant tempera- ov
ture over 97OC (207°F) or diagnosis con-
nector terminal TFA grounded) -
2E 0 Water thermo-
sensor Fan not operating (Idle) VS
Engine coolant temperature 20% (68OF)
After warm-up Approx. 2.5V f&ition switch
Below 05V
2F , 0 , , Throttle sensor , Accelerator pedal released
Accelerator pedal fully depressed
2G 0
2H 0 ATF thermosensor -30°C (-20°F) -150°C (302OF) Approx. 4.9%1.12V Ignition switch
ATF
Temp 20% (68OF) Approx. 4.6V ON
130% (266OF) Approx. 1.54V
Hold switch Switch debressed ov Ignition switch
i I I
Switch released Va ON
21 0 Throttle sensor Constant 4.5-5.5v Ignition switch
ON
I , I 2J 0 Distributor Ignition switch ON Approx. OV
(G-signal) [DOHC] or 5V _-
Idle Approx. 1.5V
2K 0 Intake air ther- Ambient air temperature 20% (68’F) Approx. 2.5V Built in airflow
mosensor meter
2L - - - -
- -
2M 0 Pulse generator Engine running at idle (N range) Above 0.6V
-
(IN)
Engine stopped (Ignition switch ON) ov
2N Pulse generator Constant ov
ground
20 0 Solenoid valve ignition switch ON Va
(Purge control) -
Idle Va
2P 0 Hold indicator Hold mode Below 2V Ignition switch
ON
Normal mode VB
23UOFX-1
1 Ul Iv
I u1
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ 20)21Vi,2~]2112Gj2E)2Cj2~ iuI1s]l~lollMIlKI1IJ1~~t~l1Cj1~
32 j3X I3V 13T13R13P13N)3L13J(3H13F( 3D 13s 2P(2N\2L12J12H12F(2D126 1V IATIlRhPjlN(1 LjlJ Ilt-illFI 1 DI 16
4-
F-l 62
Page 430 of 1164

F CONTROL SYSTEM
srmina
3A
38
3c
3D
3E
3F
3G
3H
31
3J
3K
3L
3M
3N
30
3P
3Q
3R
3s
3T I input Output Connection to
Test condition Correct voltage Remark Battery voltage t
- -
Ground (Injector) Constant OU -
- -
Ground (Output) Constant OU -
- -
Ground (CPU) Constant OU -
- -
- Ground (Input) Constant ov
0 Inhibitor switch
D range VB Ignition switch
(D range) ON
Other ranges ov
0 DRL relay Parking brake pulled with ignition switch
l DRL: Daytime
(Canada) ON (DRL OFF) Va
Running Lights
Idle (DRL ON) Below 2.5V 0
Inhibitor switch
(L range) L range
Other ranges VB
ov Ignition switch
ON
0 Inhibitor switch
(S range) S range
Other ranges Va
ov Ignition switch
ON
_-__. - -. -
0 Solenoid valve Engine speed below 5,000 rpm Below 1.5V WCS: Variable In-
(VICS)
Engine speed above 5,000 rpm VB ertia Charging
System [DOHC]
- - -
- - -
- -
- - -
- - -
- - -
0 Solenoid valve 60 [DOHC]/120 [SOHC] seconds after Below 1.5v
(Pressure regula- engine started when engine coolant tem-
tor) [BP] perature above 90% (194*F) and intake
-
air temperature above 58% (136OF)
[DOHC]/50”C (122“F) [SOHC]
Other condition at idle Va
- - - - - -
- -
-
A- - -
- -
- I -
0 ISC valve Ignition switch ON VS
l Engine signal
Monitor: Green
I I Idle I
Approx. 1 OV and red lamps
flash
I
-
- - - -
-
- - - -
- - - - - -
23UOFX-1’
‘) )
U- r, )
IJ- l-1
I 1 r
3Y I3W I3U [3S13d3&M13K 31 13Gj3EI 3C
I3A 20/2M;2K( 21 12G(2E12C12A 1 U 11 Sll o]lOll MI1 K 1 I (1 G(1 E[ 1
C 11 A
32 13x [ 3V(3~(343~I3N[3~ 3~(3~(3~13~ 136 2P12N(2L[2J12H(2F(2D126 iv I~TI~RI~P(~NIIL i~(lii(l~I lo(le
.
F-l 64