1992 MAZDA PROTEGE ecu wiring

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

CONTROL SYSTEM F
Incorrect voltage
Above OV
Always OV
Always VB
Always Va
Always OV
Always Ve
Always OV
Always VB
Always approx. OV or VB -
-
-
Always OV or Ve -
-
-
Always OV or Vs -
-
- Possible cause
VB: Battery voltage
l Poor connect at ground terminal l Open circuit in wiring from ECU to ground
l Inhibitor switch malfunction (Refer to page K-141) l Short circuit in wirina from inhibitor switch to ECU terminal 3E
l Inhibitor switch malfunction (Refer to page K-141)
. Open circuit in wiring from inhibitor switch to ECU terminal 3E
l Short circuit in wiring from DRL relay to ECU terminal IL l Short circuit in wiring from DRL relay to DRL unit
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)
l Inhibitor switch malfunction (Refer to page K-141) l Short circuit in wiring from inhibitor switch to ECU terminal 3G
l Inhibitor switch malfunction (Refer to page K-141) l Short circuit in wiring from inhibitor switch to ECU terminal 3G
l Inhibitor switch malfunction (Refer to page K-141) l Short circuit in wiring from inhibitor switch to ECU terminal 3H
l Inhibitor switch malfunction (Refer to page K-141) l Open circuit in wiring from inhibitor switch to ECU terminal 2H
l Refer to Code No.41 Troubleshooting (Refer to page F-103) -
-
-
l Refer to Code No.25 Troubleshooting (Refer to page F-102) -
-
-
l Refer to Code No.34 Troubleshooting (Refer to page F-103) -
-
F-l 65

CONTROL SYSTEM
Ve: Betterv voltaae
Incorrect voltage Possible csuse
Always OV l Main relay (FUEL INJ relay) malfunction (Refer to page F-172) l Open or short circuit in wiring from injector to ECU terminal 3U or 3V
Always Ve
l ECU malfunction
Always OV
Always Ve
l 1-2 shift solenoid valve malfunction (Refer to page K-143) l Short circuit in wiring from solenoid valve to ECU terminal 3W
I
l l-2 shift solenoid valve malfunction (Refer to page K-143) l Ooen circuit in wiring from solenoid valve to ECU terminal 3W
Always OV
l 2-3 shift solenoid valve malfunction (Refer to page K-143) l Short circuit in wirino from solenoid valve to ECU terminal 3X
Always VB
Always OV
l 2-3 shift solenoid valve malfunction (Refer to page K-143) l Open circuit in wiring from solenoid valve to ECU terminal 3X
l 3-4 shift solenoid valve malfunction (Refer to page K-143) l Short circuit in wiring from solenoid valve to ECU terminal 3Y
Always
VB l 3-4 shift solenoid valve malfunction (Refer to page K-143) l Open circuit in wiring from solenoid valve to ECU terminal 3Y
Always OV
l Lockup solenoid valve malfunction (Refer to page K-143) l Short circuit in wiring from solenoid valve to ECU terminal 32
Always Ve
l Lockup solenoid valve malfunction (Refer to page K-143) l Open circuit in wiring from solenoid valve to ECU terminal 32
23UOFX-1 E i0
F-l 67

TROUBLESHOOTING GUIDE
Symptom: Condenser fan and magnetic clutch do not operate.
03uoux-023
r
3EAR WIPER 10A OA
L
03uoux-02.
I
1 Step 1 Check fuses
1. Check the following fuses.
Fuse Amperage Location
AD FAN 20A In main fuse box
REAR WIPER 10A In fuse box
2. If the fuse is burned, check for a short-circuit in the wiring
harness before replacing it.
3. If the fuses are OK, go to Step 2.
I
23uoux-011
Step 2 Measure voltage at A/C relay connector
1. Run the engine at idle.
2. Turn the A/C and blower switches ON.
3. Measure the voltage at the following terminal wires of the
A/C relay connector. VEX Battery voltage
,
Wire
0-Q
W) Voltage Action
VB Next check wire (L/Y)
ov Repair wire (L/G)
V0 Next check wire (B/L)
ov
VB
ov
VB
ov Repair wire (L/Y)
Repair wire (B/L)
Next check wire (LIB)
Go to Step 3
Replace A/C relay
Step 3 Measure voltage at A/C switch
Measure the voltage at the following terminal wires of the A/C
switch connectors.
VB: Battery voltage
Step 4 Measure voltage at thermoswitch
Measure the voltage at the terminal wires of the thermoswitch
connector.
VB: Battery voltage
Wire
(G/R)
WB)
Voltage
VB
ov
VB
OV
Action
Repair wire (G/R)
Next check wire (G/B)
Go to Step 5
Check ECU ooeration
1 -. [ Refer to Secti6n F
u-12