1990 MAZDA 232 Workshop Manual Suplement

F2 CONTROL SYSTEM
CONTROL
SYSTEM
STRUCTURAL VIEW
OXL STOPLIGHT SWITCH CLUTCH SWITCH
INJECTOR
P/S PRESSURE
SWITCH
‘GEN SE877
DtSTRIBUTOR
/ PUMP
CONTROL UNll
CONTROL UNIT
CONNECTOR
P REStSTORlRELAY
FUEL tNJ RELAY (MAIN RELAY)
AIRFLOW METER
SOLENOID VALVE
I NEUTRAL SWITCH
(PRESSURE REGULATOR)
WATER THERMOSENSOR
93GOf2.729

CONTROL SYSTEM
WE~DOST WARNlNG BUZZER [BP TURBO]
To improve engine reliability, the overboost warning buzzer installed in the instrument cluster sounds during
overboost conditions as detected by engine
speed and intake air amount caiculations within the ECU. The
driver is thus warned to reduce engine
speed.
DETECTtON
OVERBOOST
BUZZER
TURBOCHARGE INDICATOR [BP TURBO]
When the turbocharger boost pressure calcul’ated by intake air amount and engine speed reaches the predeter-
mined level and the transaxle is in gear, the turbocharge indicator illuminates to inform the driver of turbocharge
operation.
1
AIRFLOW METER
DISTRI BUTUR
rd” i
4 NEUTRAUCLUTCH
SWITCH ECU
* CALCULATION
-, OF
BOOST
PRESSURE
TURBOCHARGE
INDICATOR

F2 CONTROL SYSTEM
KNOCK CONTROL SYSTEM [BP TURBO]
This svstem retards the ignition timina when enaine knocking occurs because of usage of low octane fuel, etc.
1NTAKE
MANIFO
KNOCK SENSOR
(INSTALLED BETWEEN No.2 AND
No.3 CYLINDER)
IGNITER
KNOCK iX?NTROL
UNIT
Operation
When the engine vibrates, the knock sensor generates a slight voltage signal that is the sent to the knock
control unit. The knock control unit determines whether the signal is a knocking signal. If it is a knocking
signal, the ignition spark is retarded according to the intensity of the knock to a maximum of 4O.
Inhibition of spark retardation
In order to improve drivability and fuel economy, the ECU inhibits the above spark retardation when the
‘engine load Ls light, the coolant temperature is below O°C (32OF), the engine is cranking during engine test
conditions.
Note
l The knock ~ensur and knock control unit cannot be inspected individually.
When a matfunction code number 05 is indicated, replace the knock controt unit or sensor
only after inspecting the related wiring and connectors.
F2-22

CONTROL SYSTEM F2
t OXYGEN SENSOR [BP TURBO]
I
CERAMlC HEATER
93GOF2-733
Because the temperature of the exhaust gas is inherently low in turbocharged engines, the BP Turbo model
uses a rapid heating ceramic heater to detect the air/fuel ratio,
PRESSURE REGULATOR CONTROL SYSTEM [BP TURBO]
PRESSURE
REGULATOR
I SOLENOID VALVE
(PRESSURE REGULATOR CONTROL)
FUEL
+ (FROM
DELIVERY PIPE1
II
FUEL INJ I
RELAY
(MAIN REU\Y)
I
II Ir
-__. _ - -’ VACUUM
CT0 DYNAMIC
Ill
CHAMBER)
BATTERY -
c
FUEL
(TO FUEL TANK)
nme*rn -.-a
To prevent percolation of the fuel during hot restart idle, vacuum to the pressure regulator k cut for 180
sec., and the fuel injection pressure is increased to slightly more than 284 kPa (2.90 kg/cm’, 41.2 psi).
Operating condition
l Coolant temperature: Above 90°C (194OF)
l Intake air temperature: Above 58OC (136OF)
g No-load condition
FZ-23

F2 CONTROLSYSTEM
AK CUT-OFF SYSTEM (AI-X)
To improve the retiability of the engine at high temperature condition, the water thermoswitch on the radiator
is switched OFF above approx. II I “C (232OF) and stops the A/C operation.
ECU
NC OPERATION BLOWER FAN
WATER
THERMOSWITCH
IABOVE
111 OC (232OF): OFF]
NC SWITCH
IGNITION
T
l 1
BLOWER SWITCH
MAGNET
CLUTCH
93GOF2-73
F2-24

SUPPLEMENTAL SERVICE INFORMATION F2
SUPPLEMENTAL SERVICE INFORMATION
The following points in this section are changed in comparison to the Mazda 323 Workshop Manual
[I 203-I U-89F (Europe) or 120410-89F {Australia)].
intake air system components [BP Turbo]
l Removalllnspectionll nstaltation
WASTEGATE [BP Turbo]
l Inspection
WASTEGATE SULENOlD VALVE [BP Turbo]
l Inspection
Turbocharger [BP Turbo]
l Inspection
l Removalllnstaltation
Air bypass valve [BP Turbo]
l Removal/hstallation
l 1 nspection
lntetcoolet [BP Turbo]
l RemovaMnspection/tnstaltation
Fuel tank
l Removal ! Inspection I Installation
Fuel pump control unit [BP Tubto]/4x4 control unit [BP SOHC]
l 1 nspection
l Replacement
Transfer pump switch
l Inspection
l Replacement
Transfer pump
l Inspection
l Replacement
Fuel pump resistor/relay
l System operation
l Inspection
injector [8P Turbo]
l Volume test
Exhaust system components
l Removal / 1 nspection / Installation
Engine control unit (ECU) [BP Turbo]
l Terminal voftage
Oxygen sensor [BP Turbo]
l Inspection
l Replacement
Knock sensor [BP Turbo]
l Replacement 93GOFZ736
F2-25

F2 SELF-DIAGNOSIS FUNCTION
SELF-DIAGNOS1S FUNCTION
OUTLINE
The self-diagnostic function and diagnosis procedure are the same as for the 2WD model. However there
are some additional malfunction codes for BP Turbo models.
93GOF2-737
MALFUNCTlON CODE NUMBERS
command of throttle
F2-26

SELF-DIAGNOSIS FUNCTtON F2
Q3en
or short ci rculi - ON
26
OFF -
ON
34
OFF
ON
42
OFF
Caution
l If there is more than one failure present, the code numbers will be indicated in numerical or-
der, lowest number first.
l After repairing a failure, turn off the ignition switch, disconnect the negative battery cable,
and depress the brake pedai for at least five (5) seconds to erase the malfunction code(s) from
the ECU memory.
f2--27