Page 286 of 1164

F TROUBLESHOOTING GUIDE
TROUBLESHOOTING GUIDE
ENGINE CONTROL OPERATION CHART
Note
Input Device and Engine Conditions
l The data in this chart is for reference only.
INPUT DEVICES APPROX,- SENSORS
MATE TIME G& THROTTLE SENSOR
(BASED ON TRIBUTOR
WATER INTAKE
10-16°C, (G. OXYGEN AIRFLOW AIR
VT
POW
.50-6OOF
SIGNAL)” ;;;;;f- SENSOR METER
AMBIENT) (Ne-SIGNAL) THERMO- TERMINAL TERMINAL yE\MINAL
CONDITIONS SENSOR (ATX)
WX)
A
c
CRANKING
-COLD ENGINE Signal has Signal has Signal has Signal has Slgnal has Slgnal has
l COLD AIR zero no affect no effect no effect no effect no effect
no effect
. COLD COOLANT on ECU on ECU on ECU on ECU on ECU
on ECU
Cool to A A
COLD START
warm: Low volume Closed Closed
Closed
-FAST IDLE
One
Medium airflow: throttle: throttle:
l COLD AIR
minute
voltage High volt-
Low volt- Low volt- throttle.
Low volt-
* COLD COOLANT
(3.5” and :zo:o, ,,Pbove 1’,“,“$; a(ogi-O,8”) ;149&“) we W)
dropping) to high
(68OF)]:
COLD DRIVEAWAY voltage A
Above
-PART THROTTLE Two (O-0.9”) 2.3”
l COLD AIR minutes
l COLD COOLANT
v v ,,
Warm: Medi- Sensor Moderate II
WARM DRIVEAWAY
volume air-
-PART THROTTLE Three N&IGNAL um voitage hot:
flow: Low
l WARM AIR minutes Sends all Vvwrox switching l WARM COOLANT cylinders 0.7V and
from high to medium
Part Part
TDC signal dropping) voltage voltage
throttle: throttle.
)
A (0.9V) (1 .o-3.5”)
to ECU
.“~ Medium Medium
HOT CRUISE
s voltage voltage
Open
l WARM AIR G-
SIGNAL”’ to low (0.8-3.0”) (4.5-5.5”) throttle:
l WARM COOLANT High
Sends No. voltage
1 cylinder (0.1”) voltage
1 (battery
TDC (com-
1 I voltage)
HOT ACCELERATION pression)
-60% THROTTLE signal to
Moderate
ECU
to strong
High Cool lo warm
voltage ;$,“,” Of j-20-4OT
f t
HOT ACCELERATION
More’ than Hot: Low (0.9”) Low (-4-‘04”F)l: W,ds open
voltage 1.5-4.3v
throttle: Wide open
-WIDE OPEN
four voltage
High volt- throttle
THROTTLE (0.5-1.5V)
minutes (Below High
0.5”) age (Above
voltage (OV)
t 1 3.OV)
I,
A 1. /I
DECELERATION
-CLOSED THROTTLE
HOT CURB IDLE
-EXTENDED
HOT ENGINE
SHUTDOWN Low
voltage
(0”) Low Closed Closed
Closed
volume throttle: throttle.
throttle.
of airflow:
~~~~!$$ (Above Low Low
Low
voltage voltage
voltage
to low 3.OV) (0.2-0.N) (4.5-5 5V) (OV)
voltage
(0.75%
t t 1 0.25”)
r v 1 I I
Sensor
hot: Low
OFF OFF voltage
-
(0.1”) until OFF OFF OFF OFF
OFF
sensw
COOIS
._-
Page 287 of 1164
![MAZDA PROTEGE 1992 Workshop Manual TROUBLESHOOTING GUIDE F
r
- SENSORS
z-----
‘RES-
‘URE
‘WITCH FRL (Dsy
ime Run-
ling
.ight)
:ONTROL
INIT
CANADA]
)FF
3attery
oltage)
T- IEUTRAL
rND
:LUTCH
iWITCHES
MTX) IIAGNO MAZDA PROTEGE 1992 Workshop Manual TROUBLESHOOTING GUIDE F
r
- SENSORS
z-----
‘RES-
‘URE
‘WITCH FRL (Dsy
ime Run-
ling
.ight)
:ONTROL
INIT
CANADA]
)FF
3attery
oltage)
T- IEUTRAL
rND
:LUTCH
iWITCHES
MTX) IIAGNO](/manual-img/28/57077/w960_57077-286.png)
TROUBLESHOOTING GUIDE F
r
- SENSORS
z-----
‘RES-
‘URE
‘WITCH FRL (Dsy
ime Run-
ling
.ight)
:ONTROL
INIT
CANADA]
)FF
3attery
oltage)
T- IEUTRAL
rND
:LUTCH
iWITCHES
MTX) IIAGNOSIS
:ONNEC-
‘OR TEN
‘ERMINAL
rEST
‘ERMINAL) IGNITION SWITCH
s kgnal has
r IO effect
C In ECU
I neutral:
.ow volt-
rge signal
II ECU
w
-
f
I
Iriving in
iny gear:
iigh volt-
ige signal
o ECU
Battery TOP-
IGHT
WITCH UHIBITOR
iWITCH
4TX) L/C
;WITCH
5
IL
IGNAL
Sl ignal has
nl 3 effect
01 n ECU
H
0
F-f
S
C
VI
si
E
te
VI
C
VI
si
i
1 T
eadlight
r rear
‘indow
efroster
Nitch
IN: High
pltage
gnal to
CU (Bat-
try
sltage)
IFF: Low
altage
gnal to
cu
3elow
.5V)
B
S'
0
C,
C
L
E
E
II
(
\i
c
E
t’
I lower
Nitch**
r Electri-
al fan
IN: Low
foltage
signal to
iCU (Be-
3w 1.W)
IFF: High
loltage
rignal to
ICU (Bat-
ev
voltage)
I
OFF ITART
‘OSITION IN
OSITION
‘ends sig
al to
CU (Bat-
?ry
oltage) #ignal has
0 effect
#n ECU ignal has
0 effect
n ECU ignal has
0 effect
n ECU ;ignal has
IO effect
rn ECU ignal has
0 effect
n ECU
rake pedal Ggnal has
IQ effect
In ECU
1NorP
ange: No
ignal to
.cu
w
-
7D
ange: No
#ignal to
.cu
Battery
foltage)
- - - - -
ends sig-
31 to ECU
jattr ?ry
Atac
-2
/heel -
Jrned:
ow volt-
ge signal
I ECU
3elow
.5V)
teering
/heel
traight
head:
ligh volt-
ge signal
) ECU
dattery .erminal
lot
Irounded:
iigh volt-
tge Signal
3 ECU
Battery
roltage)
‘erminal
Irounded:
.ow volt-
rge signal
3 ECU
Below lo signal
ent to
cu
3elow
5V) r/C switch
IN:
iends sig-
ial to
CU (Be-
IW 1.5V)
r/C switch
IFF: No
ignal to
CU (Bat-
3ry
‘oltage) )RL ON:
w ends sig-
al to
CU (Bat-
2ry
oltage) lo signal
3 ECU
3elow
.5V) )RL OFF:
3attery
oltage)
I .5V’
medal
Sends
signal to
KU
Battery
voltage)
- -
In N or P
range:
Sends sig-
nal to ECU
PV In neutral:
Low volt-
age stgnal
to ECU
(W
I -
- - -
OFF OFF OFF OFF OFF OFF OFF
OFF OFF
23UOFX-0’
+’ Blower switch: 2nd position or more
F-21
Page 290 of 1164
F TROUBLESHOOTING GUIDE
RELATIONSHIP CHART
OUTPUT DEVICE
INPUT DEVICE
DIAGNOSIS CONNECTOR
[TEN TERMINAL) 0 0 0 0
IGNITION SWITCH (START POSITION) 0 0 0 0 0 0
E/L SIGNALg4 0
0
P/S PRESSURE SWITCH 0 0
B/C SWITCH 0 0 0
INHIBITOR SWITCH (ATX) 0 0 0 0 0 0 0
NEUTRALANDCLUTCH
SWITCHES (MTX) 0 0 0 0 0 0 0
STOPLIGHT SWITCH 0
0
&TMOSPHERIC PRESSURE SENSOR
[IN ECU) o 0 0 0 0
rHROTTLE SENSOR 0 0 0 0 0 0 0
INTAKE AIR THERMOSENSOR 0 0 0 0 0
MRFLOW METER 0 0 0 0 0
3XYGEN SENSOR 0 0 0 0
JVATERTHERMOSENSOR 0 0 0 0 0 0 0
G-SIGNAL*’ 0 0
3ISTRIBUTOR
Ne-SIGNAL 0 0 0 0 0 0 0 0
-- ,.-, ,--., ,.*
+z
*3 &HC
MIL: Malfunction Indicator Lamp
r.9u”rn-” I
*’ E/L SIGNAL: Blower fan control switch second position or higher, cooling fan operating, headlights ON, or rear win-
dow defroster switch ON
F-24
Page 299 of 1164

TROUBLESHOOTING GUIDE
TEP INSPECTION ACTION
4 Check if ECU terminal voltages are OK Yes Go to next step
MTX...Especially IC, 20 and 2Q
ATX... Especially lC, 2E and 3D v page F-150
No Check for cause ~3‘ page F-151
5
Check for air leakage of intake air system com- Yes Repair or replace
ponents
No Go to next step
6 Check if engine starts when water thermosensor Yes Check water thermosensor c7 page F-158 is disconnected
Check for correct engine compression 82-10 ’ No
Check engine condition CIP page Bl-10
Engine compression: 82-10
l BP SOHC l Worn piston, piston rings or cylinder 834 kPa (8.5 kg/cm*, 121 psi)300 rpm
wall
l BP DOHC l Defective cylinder head gasket 883 kPa (9.0 kg/cm*, 128 psi)-300 rpm l Distorted cylinder head
l B8 l Improper valve seating 932 kPa (9.5 kg/cm*, 135 psi)300 rpm *Valve sticking in guide
9 Check if spark plugs are OK Yes Go to next step CT- page G-18
1.0-l .l mm
(0.039-0.043 in) DAMAGE AND
DETERIORATION No Clean, or replace c7 page G-18
10 Try known good ECU and check if condition
improves CT- page F-149
23UOFX-01 I
F-33
Page 301 of 1164
TROUBLESHOOTING GUIDE F
TEPt INSPECTION ACTION
Fuel line pressure:
More than 147 kPa (1.5 kg/cm*, 21 psi)
w page F-125
4 If OK, check injector for fuel
w page F-132
w page F-127
w page F-158
+ If OK check connections of water
osensor and ECU 2Q terminal
check connections of water
osensor and ECU 2E terminal
K, replace water ther-
w page F-83
w page F-150
Specification: Battery voltage
(Ignition switch ON)
Q If OK, replace ECU CT page F-149
+ If not OK, check wiring between
ECU and Self-Diagnosis Checker
23UOFX-0:
F-35
Page 311 of 1164
TROUBLESHOOTING GUIDE F
s TEP INSPECTION ACTION
6 Check for correct water thermosensor resistance
Yes Go to next step
w page F-158
RESISTANCE
WI
20
‘70
I No Replace water thermosensor w page F-158
A.7
0.5
lE 41
(1400,
(1%) COOLANT TEMPERATURE OC (OF)
Connect System Selector to diagnosis connector
Check if engine speed decreases as engine
Ignition timing (BTDC)
l BP DOHC : go-11 * l BP SOHC : 4*-6O
23UOFX-OS
F-45
Page 315 of 1164

TROUBLESHOOTING GUIDE F
12 ROUGH IDLE/ENGINE STALLS JUST AFTER STARTING
DESCRIP-
*Engine starts normally but vibrates excessively or stalls just after starting (acceleration from idle) TION
*Idle conditions are normal in the other conditions [TROUBLESHOOTING HINTS]
@ Fuel injection control system or idle speed control sys-
@ Idle speed misadjustment
tern malfunction @ Ignition timing misadjustment
*Start signal not input to ECU iTEl
-s-- 3
4
5 INSPECTION
-T- ACTION
Check if “00” is displayed on Self-Diagnosis
Checker with ignition switch ON w page F-82
SYSTEM,SELECT: I
r -SELECT SW: A
Check if ECU terminal voltages are OK
MTX...Especially 1 N
ATX... Especially 1T w page F-150
Connect System Selector to diagnosis connector
and set Test Switch to “SELF TEST” and check
for correct ignition timing at idle after warm-up w page F-78
Ignition timing (BTDC)
l BP DOHC : 9”-11 o l BP SOHC : 4O--6O
l B8 : 60-80
Check continuity between throttle sensor termi-
nals IDL and E CT page F-159
MTX
Clearance between throttle
lever and stopper
MTX O.lmm (0.004 in)
1 .Omm (0.039 in)
ATX 0.1 mm (0.004 in)
0.6mm (0.024 in) Continuity
Yes
No
Yes
No
Try known good ECU and check if condition
mproves w page F-149 Yes
No
Yes
Go to next step No
Check for cause Yes
In same condition as Step 3 inspection
and apply parking brake
Check for correct idle speed w page F-80
Idle speed: 700-800 rpm
No
Adjust Yes
Go to next step No
Adjust Go to next step Service Code No. displayed
Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
Check ECU terminal IF voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
d If OK, replace ECU w page F-149
* If not OK, check wiring between
ECU and Self-Diagnosis Checker c7 page F-151
3 If OK, go to next step
3 If not OK, adjust idle speed w page F-80
w page F-79
w page F-159
F-49
Page 318 of 1164
![MAZDA PROTEGE 1992 Workshop Manual F TROUBLESHOOTING GUIDE
14 IDLE MOVES UP AND DOWN/IDLE HUNTING
DESCRIP-
*Engine speeds up and down periodically at idle
TION
[TROUBLESHOOTING HINTS]
@ idle switch (built in throttle sensor) OFF MAZDA PROTEGE 1992 Workshop Manual F TROUBLESHOOTING GUIDE
14 IDLE MOVES UP AND DOWN/IDLE HUNTING
DESCRIP-
*Engine speeds up and down periodically at idle
TION
[TROUBLESHOOTING HINTS]
@ idle switch (built in throttle sensor) OFF](/manual-img/28/57077/w960_57077-317.png)
F TROUBLESHOOTING GUIDE
14 IDLE MOVES UP AND DOWN/IDLE HUNTING
DESCRIP-
*Engine speeds up and down periodically at idle
TION
[TROUBLESHOOTING HINTS]
@ idle switch (built in throttle sensor) OFF at idle
@ Air leakage
@ Fuel injection amount inconstant
spoor contact point inside airflow meter
@ Poor ignition
iTEP INSPECTION
1 Check if “00” is displayed on Self-Diagnosis
Checker with ignition switch ON
CT page F-82
SYSTEM SELECT: 1
ACTION
Yes Go to next step
No
Service Code No. displayed
Check for cause (Refer to specified
check sequence) w page F-83
“88” flashes
,,;9 Check ECU terminal 1F voltage w page F-150
Specification: Battery voltage
(Ignition switch ON)
W: SELF TEST + If OK, replace ECU KIT page F-149
ELECT SW: A + If not OK, check wiring between
ECU and Self-Diagnosis Checker
2 Check for correct intake manifold vacuum at idle Yes Go to next step
Intake manifold vacuum:
More than 450 mmHg (17.7 inHg)
No Low vacuum
Check for air leakage at intake air
system
3 Check if air cleaner element is clean Yes Go to next step
w page F-79
No Replace air cleaner element
4
Disconnect high-tension lead at idle and check if Yes Go to next step
engine speed decreases equally at each cylinder
No Go to Step 9
5 Check if ECU terminal voltages are OK Yes Go to next step
w page F-150
No Check for cause KII page F-151
6
Connect System Selector to diagnosis connector Yes Go to next step
and set Test Switch to “SELF TEST” and check
for correct ignition timing at idle after warm-up
w page F-79
Ignition timing (BTDC)
l BP DOHC : 9”-11 o l BP SOHC : 4O-8” l B6 : 6O--8O No Adjust ignition timing r-7 page F-79
TEST SWITCH . .
F-52