1992 MAZDA PROTEGE wiring

CONTROL SYSTEM F
SMALL TYPE
03UOFX.20:
03UOFX-20
23UOFX-13
TERMINALS
AANDB
c “.w a ,.1/M rrmrrm
_-
03UOFX-201
ENGINE CONTROL UNIT (ECU)
Removal / Installation
1. Remove the side walls (driver’s side and passenger’s side).
(Refer to page S-94.)
2. Remove the bolts and nuts.
3. Disconnect the ECU connectors.
4. Install a
new ECU in the reverse order of removal.
Inspection
1. Disconnect the ECU connectors.
2. Connect the
SSTs (Engine Signal Monitor and Adapt-
er)
to the ECU as shown,
3. Set the SST (Sheet) on the Engine Signal Monitor with
the specified side fancing up as shown.
Note
l MTX...48 PIN
l ATX...84 PIN
4. Measure the voltage at each terminal.
(Refer to pages F-150 to F-167.)
5. If any ECU terminal voltage is incorrect, check the related
input or output devices and wiring. If no problem is found,
replace the ECU. (Refer to above.)
Caution
l Never apply voltage to SST terminals A and B.
F-l 49

CONTROL SYSTEM F
VB: Battery voltage
incorrect voltage POBSible cause
Alwvs OV’ l ROOM IOA fuse burned l Open circuit in wiring from ROOM IOA fuse to ECU terminal 1A
Always OV
l Main relay malfunction (Refer to page F-171) l Open or short circuit in wiring from main relay to ECU terminal 1B
I
Always OV (Starter turns) l Open or short circuit in wiring from starter interlock switch (USA), ignition
switch (CANADA), to ECU terminal 1C
I
Always OV
Always Vs
Always approx. 5V
l Main relay (FUEL IWJ relay) malfunction (Refer to page F-171) l Open circuit in wiring from main relay to diagnosis connector terminal +B l Open or short circuit in wiring from diagnosis connector terminal MEN to
ECU terminal 1D
l Poor connection at ECU connector l ECU malfunction
l ECU malfunction
Always below
23 MIL always ON
MIL never ON
l Short circuit in wiring from combination meter to ECU terminal 1E l ECU malfunction
l Open circuit in wiring from combination meter to ECU terminal 1E
I
Always Ve l Poor connection at ECU connector l ECU malfunction
Always below
2.5V
Always
VB
No display on Self- * Main relay (FUEL INJ relay) malfunction (Refer to page F-171)
Diagnosis Checker l Open circuit in wiring from main relay to diagnosis connector terminal +B
“88” displayed and
l Open or short circuit in wiring from diagnosis connector terminal FEN to
buzzer sounds con- ECU terminal 1F
tinuously
l Poor connectron at ECU connector l ECU malfunction
Always OV
l Short circuit in wiring from igniter to ECU terminal 1G
I -
I -
I
I -
I -
I
Always below
2.5V
Always VB AIC does not operate l A/C relay malfunction (Refer to page U-55) l Open circurt in wiring from ignition switch to A/C relay l Open circuit in wiring from A/C relay to ECU terminal 1J
A/C switch OFF but
l Short circuit in wiring from A/C relay to ECU terminal IJ
AIC operates l ECU malfunction
l Poor connection at ECU connector l ECU malfunction
Always below l.OV
l Short circuit in wiring from diagnosis connector terminal TEN to ECU termi-
nal 1K
Always Vs
l Open circuit in wiring from diagnosis connector terminal TEN to ECU termi-
nal 1K
l Open circuit in wiring from diaonosis connector terminal GND to ground
Always below
2.W
Always Va DRL ON when ignition
l Short circuit in wiring from DRL relay to ECU terminal IL
switch ON l Short circuit in wiring from DRL relay to DRL unit
DRL never ON
l Open circuit in wiring from DRL relay to ignition switch
l Parking brake switch always ON l DRL unit malfunction (Refer to page T-33)
23UOFX- 134
F-l 51

CONTROL SYSTEM F
Ve: Battery voltage
Incorrect voltage
1, -
Always below l.OV
Always Ve
Always below I.OV (Stoplight OK)
Always below l.OV
Always
VB
Always below 25V (Blower fan OK)
Always
VB (Blower fan OK)
Always below 1 .OV
(Electrical cooling fan OK)
Always below 1 .OV (Blower fan OK)
Always
VB (Blower fan OK)
Always below
1 .ov
Always below l.OV Illumination lamp
ON when rear
window defroster
switch ON
Illumination lamp
never ON
(Headlights OK)
Always below l.OV
Always Ve Possible cause
-
l Throttle sensor misadjustment (Refer to page F-169)
l Short circuit in wiring from throttle sensor to ECU terminal 1N l ECU malfunction
l Throttle sensor misadjustment (Refer to page F-169) l Open circuit in wiring from throttle sensor to ECU terminal IN l Open circuit in wiring from throttle sensor to ECU terminal 2D
l Open circuit in wiring from stoplight switch to ECU terminal 10
l P/S pressure switch malfunction (Refer to page F-173) l Short circuit in wiring from P/S pressure switch to ECU terminal 1P l ECU malfunction
l P/S pressure switch malfunction (Refer to page F-173) l Open circuit in wiring from P/S pressure switch to ECU terminal 1P l Open circuit in wiring from P/S pressure switch to ground
l A/C switch malfunction (Refer to page U-55) l Short circuit in wiring from A/C switch to ECU terminal 10 l Poor connection at ECU connector l ECU malfunction
l A/C switch malfunction (Refer to page U-55) l Open circuit in wiring from A/C switch to ECU terminal 1Q l Open circuit in wirina from A/C switch to blower control switch
l Open or short circuit in wiring from fan relay to ECU terminal 1R l ECU malfunction
l Short circuit in wiring from blower control switch to ECU terminal 1s l Poor connection at ECU connector l ECU malfunction
l Open circuit in wiring from blower control switch to ECU terminal IS
I
l Open or short circuit in wiring from rear window defroster switch to ECU
terminal 1 T
l Open circuit in wiring from ignition switch to rear window defroster switch l Rear window defroster switch malfunction (Refer to page T-21)
l Open or short circuit in wiring from headlight relay to ECU terminal 1U
(Refer to page F-152)
l Neutral switch malfunction (Refer to page F-173) l Clutch switch malfunction (Refer to page F-172) l Short circuit in wirino from ECU terminal IV to neutral or clutch switch
l Neutral switch malfunction (Refer to page F-173) l Clutch switch malfunction (Refer to page F-172) l Open circuit in wiring from ECU terminal 1V to neutral or clutch switch l Poor connection at ECU connector
23UOFX-136
F-l 53

CONTROL SYSTEM
Ve: Battery voltage
Incorrect voltage
I Possible cause
4bove OV
l Poor contact at ground terminal l Open circuit in wiring from ECU to ground
Always approx. OV or approx. 2V
l Refer to Code No.02 Troubleshooting (Refer to page F-86) -
r\lways approx. OV or approx. 1.W - l Refer to Code No.03 Troubleshooting (Refer to page F-88)
Approx. 4.5-5.5V (California)
Always OV (Canada)
l Open circuit in wiring from ECU terminal 2H to ground
l Short circuit in wiring from ECU terminal 2l-i to main relay (FUEL INJ relay) - -
Approx. 4.5--55V l ECU malfunction
Always OV
l Short circuit in wiring from ECU terminal 2K to throttle sensor, or airflow
meter
Below 4.5V or above 5.5V
l Poor connection at ECU connector l ECU malfunction
1
l ECU malfunction
Always OV
l Throttle sensor malfunction (Refer to page F-169) l Short circuit in wiring from ECU terminal 2L to throttle sensor l Poor connectron at ECU connector l ECU malfunction
Always 4.5--5.W
Always constant
l Throttle sensor misadjustment (Refer to page F-169) l Open circuit in wiring from ECU terminal 2L to throttle sensor l Open circuit in wiring from ECU terminal 2L to ECU terminal 2D
l Open circuit in wiring from ECU terminal 2M to throttle sensor
l Open circuit in wiring from ECU terminal 2K to throttle sensor l Open circuit in wiring from ECU terminal 20 to throttle sensor
Always above 1V 1
l Throttle sensor misadjustment
OV after warm-up
Always approx. 1V after warm-up (
l Refer to Code No.15 Troubleshooting (Refer to page F-98)
I * Refer to Code No.1 7 Troubleshooting (Refer to page F-100)
Always OV or 4.5-5.5V
Always OV or 4.5~-5.W
I l
Refer to Code No.08 Troubleshooting (Refer to page F-90) l
Refer to Code No.10 Troubleshootrng (Refer to page F-94)
Always OV or 4.5-5.W l
Refer to Code No.09 Troubleshooting (Refer to page F-92) -
23UOFX-131
F-l 55

CONTROL SYSTEM
Incorrect voltage
Always OV or VB
Always OV or VS
VB: BBttWy voltage
Possible cause
l Refer to Code No.41 Troubleshooting (Refer to page F-103)
l Refer to Code No.25 Troubleshooting (Refer to page F-102)
Always OV
l Main relay (FUEL INJ relay) malfunction (Refer to page F-172)
6 Open or short circuit in wiring from injector to ECU terminal 2U or 2V
Always Ve
l ECU malfunction
Always OV or
VB
Always OV or Va
l Refer to Code No.34 Troubleshooting (Refer to page F-103)
l Refer to Code No.26 Troubleshooting (Refer to page F-102)
23UOFX-140
F-t 57

CONTROL SYSTEM F
VB: Battery voltage
Incorrect voltage Possible cause
Always OV l ROOM 10A fuse burned l Open circuit in wiring from ROOM 10A fuse to ECU terminal 1A
Always OV
l Main relay malfunction (Refer to page F-171) l Open or short circuit in wiring from main relay to ECU terminal 1B
Always OV (Starter turns)
l Open or short circuit in wiring from or inhibitor switch (ATX) to ECU termi-
nal 1C
Always OV
Always Ve
Always 4.5~5.5U
l Main relay (FUEL INJ relay) malfunction (Refer to page F-171) l Open circuit in wiring from main relay to diagnosis connector terminal +B l Open or short circuit in wiring from diagnosis connector terminal MEN to
ECU terminal 1D
l Poor connection at ECU connector l ECU malfunction
l ECU malfunction
Always below
25v
Always Va MIL always ON
MIL never ON
l Short circuit in wiring from combination meter to ECU terminal 1E l ECU malfunction
l Open circuit in wiring from combination meter to ECU terminal 1E
l Poor connection at ECU connector l ECU malfunction
Always below
2.5V
Always VB No display on Self- * Main relay (FUEL INJ relay) malfunction (Refer to page F-171)
Diagnosis Checker
l Open circuit in wiring from main relay to diagnosis connector terminal +B
“88” displayed and
l Open or short circuit in wiring from diagnosis connector terminal FEN to
buzzer sounds con- ECU terminal 1F
tinuously
l Poor connection at ECU connector l ECU malfunction
Always OV
l Short circuit in wiring from igniter to ECU terminal 1G
Always below 1 .OV (Headlights OK)
l Open or short circuit in wiring from headlight relay to ECU terminal 1H
(Refer to page F-171)
Always OV
Always VB
Always OV Illumination lamp
ON when rear
window defroster
switch ON
Illumination lamp
never ON
Approx. 5V (California)
Always OV (Canada)
l Short circuit in wiring from diagnosis connector terminal TEN to ECU termi-
nal II
l Open circuit in wiring from diagnosis connector terminal TEN to ECU termi-
nal II
l Open circuit in wiring from diagnosis connector terminal GND to ground
l Open or short circuit in wiring from rear window defroster switch to ECU
terminal 1 J
l Open circuit in wiring from ignition switch to rear window defroster switch l Rear window defroster switch malfunction (Refer to page T-21)
l Open circuit in wiring from ECU terminal 1K to ground
l Short circuit in wiring from ECU terminal 1K to main relay (FUEL INJ relay)
23UOFX-14: 2
f-1 59

CONTROL SYSTEM
Incorrect voltage Possible cause
VB: Battery voltage
Always below
2.W A/C does not operate l A/C relay malfunction (Refer to page U-55) l Open circuit in wiring from ignition switch to A/C relay l Open circuit in wiring from A/C relay to ECU terminal IL
AIC switch OFF but
l Short circuit in wiring from A/C relay to ECU terminal 1L
A/C ooerates l ECU malfunction
Always Va
l Poor connection at ECU connector l ECU malfunction
Always OV
l Vehicle speed sensor malfunction (Refer to page K-143)
l Short circuit in wiring from vehicle speed sensor to ECU terminal 1M
l Vehicle speed sensor malfunction (Refer to page K-143) l Open circuit in wiring from vehicle speed sensor to ECU terminal 1M
Always OV
l P/S pressure switch malfunction (Refer to page F-173) l Short circuit in wiring from P/S pressure switch to ECU terminal 1P l ECU malfunction
Always Va
Always below 2.5V (Blower fan OK)
Always Ve (Blower fan OK)
l P/S pressure switch malfunction (Refer to page F-173) l Open circuit in wiring from P/S pressure switch to ECU terminal 1P l Open circuit in wiring from P/S pressure switch to ground
l A/C switch malfunction (Refer to page U-55) l Short circuit in wiring from A/C switch to ECU terminal IQ l Poor connection at ECU connector l ECU malfunction
l A/C switch malfunction (Refer to page U-55) l Open circuit in wiring from A/C switch to ECU terminal 1Q l Open circuit in wiring from A/C switch to blower control switch
Always OV (Blower fan OK)
Always VB (Blower fan OK)
Always below 1 .OV (Stoplight OK)
l Short circuit in wiring from blower control switch to ECU terminal 1s l Poor connection at ECU connector
l ECU malfunction
l Open circuit in wiring from blower control switch to ECU terminal 1s
l Open circuit in wiring from stoplight switch to ECU terminal 10
Always OV
Always Ve
l Inhibitor switch malfunction (Refer to page K-141) l Short circuit in wiring from inhibitor switch to ECU terminal 1R
l Inhibitor switch malfunction (Refer to page K-141) l Open circuit in wiring from inhibitor switch to ECU terminal 1R
Always OV
l Cruise switch malfunction (Refer to page T-21) l Short circuit in wiring from cruise switch to ECU terminal 1s
l Cruise switch malfunction (Refer to page T-21) l Open circuit in wiring from cruise switch to ECU terminal IS
Always OV
l Throttle sensor misadjustment (Refer to page F-169) l Short circuit in wiring from throttle sensor to ECU terminal 1T
l ECU malfunction
Always Va
I
l Throttle sensor misadjustment (Refer to page F-169) l Open circuit in wiring from throttle sensor to ECU terminal 1T
-
I - - -
Always approx. OV or approx. 2V l Refer to Code No.02 Troubleshooting (Refer to page F-86)
F-l 61

CONTROL SYSTEM F
Incorrect voltage Possible cause ____-__l_ll____-
Always approx. OV or approx. 5V l Refer to Code No.08 Troubleshooting (Refer to page F-90)
IV after warm-up
Jlways approx. IV after warm-up
l Refer to Code No.15 Troubleshooting (Refer to page F-98)
l Refer to Code No.1 7 Troubleshooting (Refer to page F-100)
qlways OV
Electrical cooling fan OK)
l Open or short circuit in wiring from fan relay to ECU terminal 20 l ECU malfunction
I Always approx. OV or approx. 5V l Refer to Code No.09 Troubleshooting (Refer to page F-92)
Always constant
C\lways above 1V
4lways constant . Open circuit in wiring from ECU terminal 2F to throttle sensor
l Open circuit in wiring from ECU terminal 21 to throttle sensor l Open circuit in wiring from ECU terminal 3D to throttle sensor
l Throttle sensor misadjustment
l ATF termosensor malfunction (Refer to page K-142) l Open or short circuit in wiring from ATF termosensor to ECU terminal 2G
c\lways OV
l Hold switch malfunction (Refer to page K-140) l Short circuit in wiring from hold switch to ECU terminal 2H
4lways Va
l Hold switch malfunction (Refer to page K-140) l Open circuit in wiring from hold switch to ECU terminal 2H
Always OV
l Short circuit in wiring from ECU terminal 21 to throttle sensor airflow meter,
or water thermosensor
l Poor connection at ECU connector
Below 4.W or above 5.W
Always approx. OV or approx. I..% l ECU malfunction
l ECU malfunction
l Refer to Code No.03 Troubleshooting (Refer to page F-88)
Always approx. OV or approx. 5V 9 Refer to Code No.10 Troubleshooting (Refer to page F-94)
I
- - VB:
Battery voltage
Always constant
l Pulse genrotor malfunction (Refer to page K-142) l Open or short circuit in wiring from pulse generator to ECU terminal 2M
Above OV
l Poor connection at ground terminal l Open circuit in wiring from ECU terminal 2N to ground
F-l 63