1992 MAZDA PROTEGE cooling

F TROUBLESHOOTING GUIDE
STEP INSPECTION ACTION
5 Check for correct fuel line pressure at idle Yes Check if fuel line pressure decreases
w page F-129 when accelerating quickly
Fuel line pressure: + If it decreases, check for clogging
265-314 kPa (2.7-3.2 kg/cm’, 36-46 psi) between fuel pump and pressure
(Vacuum hose to pressure regulator dis- regulator
connected) * If not decrease, go to next step
INSTALL CLAMPS No Low pressure
Check fuel line pressure while pinching
fuel return hose
c3 If fuel line pressure quickly in-
creases, check pressure regulator w page F-129
c3 If fuel line pressure gradually in-
creases, check for clogging be-
tween fuel pump and pressure
regulator
If not clogged, check fuel pump
maximum pressure w page F-126
6 Check if cooling system is OK Yes Go to next step
w page E-13
No Repair or replace
l Thermostat w page E-9
l Electric cooling fan w page E-16 l Radiator w page E-6
7 Try known good ECU and check if condition Yes Replace ECU CT page F-149
improves
CT= page F-149 No
Change fuel to another brand or use
higher octane fuel
23lJOFX.0: .-._ ,
F-72

F ENGINE TUNE-UP
23UOFX-046 Note
l When the parking brake is not applied, the idle
speed for ATX model (Canada) is approx. 800 rpm. Idle Speed
1. Perform “Preparation”. (Refer to page F-79.)
2. Apply parking brake.
3. Check that the idle speed is within specification.
Idle speed (Neutral or P range): 700-800 rpm
Caution
l Check the idle speed without the electric cooling
fan operating.
4. If not within the specification, adjust the idle by turning the
air adjusting screw.
5. Disconnect the SST.
F-80

SELF-DIAGNOSIS FUNCTION F
SWITCH MONITOR FUNCTION
Individual switches can be inspected by the SST (Self-Diagnosis checker).
Note
l The TEN terminal of the diagnosis connector must be grounded and the ignition switch ON
(engine stopped).
l If either of the switches remain activated, the monitor lamp will be illuminated.
ECU
NEUTRAL SWITCH (MTX)
CLUTCH SWITCH (MTX)
=d-’ 1
BATTERY
INHIBITOR SWITCH (ATX)
STOPLIGHT SWITCH (MTX)
HEADLIGHT SWITCH MONITER LAMP
REAR WINDOW (SELF-DIAGNOSIS CHECKER)
DEFROSTER SWITCH
AIC SWITCH
BLOWER SWITCH
THROTTLE SENSOR asp-
- _
COOLING FAN SWITCH
03UOFX
Switch
Clutch switch
Neutral switch (MW
(M-W Self-Diagnosis Checker (Monitor lamp)
Light ON Light OFF Pedal released Pedal depressed
In gear Neutral Remark In gear
Clutch pedal released
Inhibitor switch
(ATX) L, S, D or R range
N or P range -
Throttle sensor Pedal depressed (Not fully) Pedal released/fully depressed -
Stoplight switch
Pedal depressed Pedal released -
Headlight switch
ON
OFF Headlights/parking lights: ON
Blower switch
ON
OFF Blower switch at 2nd or
above position
AIC switch
ON OFF Fan speed control at 1st po-
sition
Rear window defroster
switch ON
OFF -
Water thermoswitch Fan operating Fan not operating -
23UOFX-084
F-l 05

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 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

FUSE AND JOINT BOX
FUSES
Specifications
Main fuse block
Fuse Color
FUEL INJ 30A Pink
HEAD 30A Pink
MAIN 80A Black
BTN 60A Green
AD FAN 30A Pink
ST SIG 10A Red
ELEC FAN 30A Pink Protected circuit
EGI system
Headlight
Cooling fan, Power window, Sunroof, Wiper and washer, Air conditioner
Door lock, Charging system
Additional cooling fan
Fuel pump
Cooling fan
Fuse box
23UOTX-001
Specifications
Fuse
REAR WIPER 10A
HAZARD 15A
ROOM IOA
ENGINE 15A
RADIO 15A
DOOR LOCK 30A
BELT 30A
POWER WINDOW 30A Color
Red
Blue
Red
Blue
Blue
Green
Green
Green Protected circuit
Rear wiper and washer
Hazard warning
Clock, interior lamp, Cargo compartment lamp, Trunk compartment lamp
Alternator
Audio
Power door lock
Passive shoulder belt
Power window
1
T-13

U
HEATER AND
AIR CONDITIONER SYSTEMS
INDEX ...................................................... u- 2
HEATER ................................................
AIR CONDITIONER ................................. ;r ;
TROUBLESHOOTING GUIDE.. .................... U- 4
CIRCUIT DIAGRAM ................................. u- 4
ELECTRICAL TROUBLESHOOTING TOOLS. U- 5
HEATER ................................................... u-20
STRUCTURAL VIEW ................................ u-20
HEATER UNIT ........................................ u-21
BLOWER UNIT ....................................... U-23
HEATER CONTROL UNIT.. ....................... U-26
AIR CONDITIONER .................................... u-30
STRUCTURAL VIEW ................................ u-30
REFRIGERANT SYSTEM ........................... u-31
COOLING UNIT ...................................... U-38
COMPRESSOR ....................................... u-41
MAGNETIC CLUTCH ............................... u-51
RECEIVER/DRIER .................................... U-52
CONDENSER ......................................... u-53
REFRIGERANT LINES .............................. u-54
REFRIGERANT PRESSURE SWITCH No.1.. . U-55
REFRIGERANT PRESSURE SWITCH No.2.. . U-55
A/C RELAY ............................................ U-56
CONDENSER FAN RELAY.. ......................
CONDENSER FAN .................................. z-f;
-
A/C SWITCH .......................................... u-57
23UOUX-001

INDEX U
AIR CONDITIONER
-1 c.Juuux-002
1 . Compressor 6. Refrigerant pressure switch No.2
Removal / Installation.. ................ page U-41 Inspection..
................................. page U-55
Disassembly I Assembly .............
page U-43 7. Condenser fan
Adjustment ................................. page U-46 Removal / Installation
.................. page U-57
2. Magnetic clutch Inspection ...................................
page U-57
Disassembly I Assembly .............
page U-51 8. Cooling unit
Inspection.. .................................
page U-51 Removal I Installation ..................
page U-38
Adjustment .................................
page U-51 Disassembly / Assembly..
........... page U-39
3. Condenser Replacement .............................. page U-39
Removal I Installation.. ................
page U-53 On-vehicle inspection..
............... page U-40
Inspection ...................................
page U-53 Inspection..
................................. page U-40
4 . Receiver/Drier
9. A/C relay
Removal I Installation.. ................
page U-52 Inspection ................................... page U-56
5. Refrigerant pressure switch No. 1
10. Condenser fan relay
Inspection.. .................................
page U-55 Inspection ................................... page U-56
u-3