cooling MAZDA 232 1990 Suplement User Guide

E OUTLINE
OUTLINE
OUTttNE OF CONSTRUCTION
The cooling system in the 323 4WD model is basically the same as in the 323 2WD model.
Although there is no fundamental change from the BP DOHC of the 2WD model, the coolant circulation
path has been changed to direct coolant to the water-cooied turbocharger.
A two-stage thermostat is used in the BP DUHC turbocharged engine to stabilize the engine coolant tem-
peratu re.
The radiator and cooling fan specifications are different. The BP DOHC turbocharged engine of the 4WD
model uses a two-speed electric cooling fan.
93GOEX-704
COOLANT FLOW CHART (BP DOHC TURBO)
E-4

RADIATOR AND COOLING FAN
The radiator and cooling fan specifications are revised.
Specifications
r
EnginelTransaxle BP SOHC 1 BP DOHC Turbo
ATX I
Item MTX MTX 1 Radiator I
Width 647 +
+
Core size
mm (in) H etght 390 t *-
Depth 16 25 e
Fm pnch
mm (in) 1.3 t c
Heat dissipaton capacity kcallh
38,800 43,800 C
Type -
Double tube - Transaxle oil cooler
Heat dissipation capacity
-
kcal/h I 1,650 -
Cooling fan
Number of biades
4 5 +
Outer drameter
mm (in> 320
340 C
Capacity
w-v 80-12 160-12 c
Current
A
1 I 6.6 * 1 Hi : 13.3 + 7 0% max. + Lo: 8.8 + 10% max.
93GOEX-708
OIL COOLER (ATX
;ECTION A-A
4WD MODEL ZWD MODEL
I
DEPTH E-7

E OUTLINE
ELECTRIC COCUNG FAN SYSTEM (BP DOHC TURBO)
System Circuit
I I
WITH A/C
r----‘-- -___- ---------.--------;
ADDITIONAL
FAN
MOTOR
I
II 1 A/C RELAY
RAD1ATdTHERMOSWITCH
ABOVE 105% I221 OF-): ON +IIAGNOSlS
CONNECTOR
WATER
THERMOSWlTCH
ABOVE 97% (207OF): ON
Operation 1. When the coolant temperature exceeds 97OC (207*F), the water thermoswitch turns ON to close the No.7
relay, and connects the + I and -1 terminals of the fan motor
connector. The fan motor turns at low
speed (about 1,660 rpm).
2. When the coolant temperature exceeds 105OC (221 OF), the radiator thermoswitch turns ON, to close the
No.2 and No.3 relays, and connects
the +2 and -2 terminals of the fan motor connector. The fan mo-
tor turns at high speed (about 2,200 rpm).
3. if the vehicle is equipped with air conditioning, the cooling fan motor operates whenever the
NC switch
and the blower switch are on, regardless of
the coolant temperature. Also, when the A/C switch and the blower switch are on, the A/C retay closes
to operate the additional fan
motur.
Note
l The water thermoswitch and the cooling fan reIay are normally-open switches.
Checking cooling fan operation 1. Jump across the TFA and the GND terminals
of the diagnosis connector with a jumper wire.
2. Turn the ignition switch to ON and verify that the cooling fan operates smoothly.
Note
l When the water thermoswitch connector is disconnected, the cooling fan wiif not operate.
E-8

SUPPLEMENTAL SERVICE INFORMAT1ON, THERMOSTAT E
SUPPLEMENTAL SERVICE INFURMATtON
The following points in the section are changed in comparison with Workshop Manual [Europe (1203-l 0-89F),
Australia (I 204-I 0-89f)].
Thermostat (BP DUHC Turbo only)
l Inspection
Electric cooling fan system (BP DOHC Turbo only)
l System inspection
Fan motor
l 1 nspection
Water thermoswitch (BP DOHC Turbo only)
l tnspection
Radiator thermoswitch (BP DOHC Turbo only)
l Removal I Inspection I Installation
Fan relay (BP DOHC Turbo only)
l Removal ! Inspection 93GOEX-710
-
THERMOSTAT (BP DOHC TURBO)
SUB-V E
‘A
/ INSPECTKM
1. Visually check that the thermostat valve is airtight.
2. Place the thermostat and a thermometer in water.
3. Heat the water and check the following:
Initial-opening temperature:
Main: 86.5-89.5% (188--t93°F)
Sub : 83.5-86.5OC (f82--f88QF)
Full-open temperature: 100°C (212°F)
Full-open lift
Main: 8.Umm CU.31 in) min.
Sub : f.5mm (0.06 in) min.
E-9

E ELECTRIC COOLING FAN SYSTEM
ELECTRIC COOLING FAN SYSTEM (BP
DUHC TURBO)
SYSTEM ClRCUIT
r
WITH A/C
r-- _______ ------
I ADDITIONAL
1 FAN
I PRESSL
SWITCH
I WATER
THERMOSWfTCtl
ABOVE 87OC (207OF): ON
RADlATOjl THERMOSWITCH
ABOVE 105*C (221 “I=): ON
8 93GOEX-719
-
%
J--- QY- -THERMOME?ERsi-=i
--
--------L-
93GOEX-7 i 2
E-10 SYSTEM INSPECTION
1. Jump across the test fan (TFA) terminal and the ground
(GN D) terminal of the diagnosis connector.
2. Turn the ignition switch ON and verify that the fan operates.
If the fan does not operate, inspect the cooling fan system
components and wiring harness.
3. Remove the radiator cap and place a thermometer in the
radiator filler neck.
4. Start the engine.
5. Verify that the fan operates when the coolant temperature
reaches approx. 97*C (207°F).
If it does, check the water thermoswitch.
(Refer to page
E--i I.)

F2 TURBOCHARGER CONTROL [BP TURBO]
93GOF.Z721
!=2-14 LARGE
+ FULLY OPEN
BYPASS AIR
i 8EGlNNIp
AMOLIN OF OPEN
SMALIL
430 VACUUM
(5-l) mmt-lg
TURBOCHARGER OnW
INLET
lntercooler
The air-to-air intercooler utilizes fresh air flow through the in-
tercooler core to reduce the intake air temperature.
If
the air compressed by the turbocharger was sent directly
into the combustion chamber without passing through the in-
tercooler, the charging air efficiency would be
reduced by the
high temperature of the intake aii-.
The intercooler, by cooling this high temperature air, substan-
tially increases the charging air efficiency
and engine output,
as well as supressing ignition knocking by reducing the com-
bustion gas temperature.
The intercooler is mounted at
the left front of the vehicle.
Air Bypass Valve
The air bypass valve bypasses intake air from the air funnel
to before the turbocharger in order to reduce air vibration noise
during deceleration.
When the throttle valve is closed suddenly during high-rpm
and heavy-load operation, air vibration occurs between the
throttle vatve and the turbocharger as a result of pressuriza-
tion
caused by inertia of the intake air. This system prevents
such noise.

I
F2
fNSPECTlON ACTION
I Check if cootrng system IS OK’
YES Go to next step
No Repair or reptace
l Thermostat l
l Electric cooling fan * l Radiator*
5 Try known good ECU and check if condltlon Yes Replace ECU * rnproves
NO Change fuel to another brand or use
higher octane fuel
l Refer to 323 Workshop Manual [1203-l O-89F (Europe) or It 204-I O-89F (Australia)]. %%‘3OF2-748 -
F2-4 I

TURBOCHARGER CONTROL SYSTEM F2
INTERCOOLER
RemovaI ! Inspection / Installation
1. Remove in the order shown in the figure.
2. Inspect the intercooler for crack or damage. Replace it if necessary.
3. Install in the reverse order of removal
19-25 (1.9-2.6,
(80-l 10 cm-kg, 69-95 in-lb)
cm-kg, 69-95 in-lb) 14-
1. Air cleaner and airflow meter assembly
2. Battery cooling duct
3. Air hose
4. Bracket 5 Undercover
6. Air hose
7. I ntercooler
N-m (m-kg, ft-lb)
93GOF2-761
F2-49

CONTROL SYSTEM F2
Incorrect voltage
Always below 1 .OV Possible cause
l Throttle sensor misadjustment l Short circuit in wiring from throttle sensor to ECU terminal IN l ECU malfunction
Always approx. f 2V
Atways below 1 .OV (Stopfights OK)
Always below 1 .OV
l Throttle sensor misadjustment l Open circuit in wiring from throttle sensor to ECU terminal IN l Open ctrcuit in wiring from throttle sensor to ECU terminal 20
l Open crrcurt in wiring from stoplight switch to ECU terminal 10
l P/S pressure switch malfunction l Short circuit in wirrng from P/S pressure switch to ECU termrnai 1 P
l ECU malfunction
Always approx. 12V
Atways below 2.5V (Btower fan OK) . P/S pressure switch malfunction
l Open circuit in wiring from P/S pressure switch to ECU terminal I P l Open circuit in wiring from P/S pressure switch to ground
l A/C switch malfunction l Short circuit in wiring from A/C switch to ECU terminal 1 Q l Poor connection at ECU connector l ECU malfunction
Always approx. 12V (Blower fan OK)
l ’ A/C switch malfunction l Open c~rcurt in wiring from NC switch to ECU terminal 1Q l ken circuit H-I winnu from A/C switch to blower control switch
Always below 1.W
l Open or short circuit in wiring from fan relay to ECU terminal IR
(Electrkal cooling fan UK} l ECU malfunctron
Always below 1 .OV (Blower fan OK)
l Short crrcutt in wiring from blower control swrfch to ECU terminal IS l Poor connection at ECU connector l ECU malfunction
Always approx. 12V (Blower fan OK)
Always below Illumination lamp
1.w ON when rear
window defroster
switch ON 1
l Open circurt in wrring from blower control switch to ECU terminat IS
I
l Open or short circuit rn wiring from rear window defroster switch to ECU
terminal 1 T
ftlumination lamp
never ON
l Open circuit in wiring from ignition switch to rear window defroster switch
l Rear window defroster switch malfunction I
Always below 1 .OV (Headlights OK)
l Open or short circurt in wiring from headlight relay to ECU termtnal 1 U
Always below 1 .OV
Always approx. l2V
l Neutral switch malfunction l Clutch switch malfunction l Short circuit in wiring from ECU terminal IV to neutral or clutch switch
l Neutral switch maifunctton l Clutch switch malfunction l Open circuit in wiring from ECU terminal IV to neutral or clutch swttch
l Poor connection at ECU connector
93GOFZ789
F2-63