radiator MAZDA 626 1987 Service Manual

4 A IGNITION TIMING CONTROL SYSTEM
IGNITION TIMING CONTROL SYSTEM
F8 and FE (12-VALVE)—ATX (ECE, Singapore, and Hong Kong)
Ignition coil
76G04A-160
This system consists of the distributor, solenoid valve, and several switches, vacuum to the vacuum
control unit of the distributor is cut when the conditions below are met.
Item Condition
Engine speed Below 2,300 rpm
Selector lever position Other than P and N range
Coolant temperature Engine coolant: below 72°C (162°F) Radiator coolant: above 17°C (65°F)
4A—80

4A CONTROL SYSTEM
RELATIONSHIP CHART
O: Related
X
: Not
related
IGNITION COIL
X X
O O O
X
O
X

WATER
THERMO
SWITCH
RADIATOR O O
X X X X
o O WATER
THERMO
SWITCH INTAKE
MANIFOLD o
X X X X
O o
X

VACUUM SWITCH
X X X X X X X
O
IDLE SWITCH
X X
O O O
X X X

A/C SWITCH
X X X X X
O
X X

P/S SWITCH
X X X X X X X X

E/L SWITCHES
/ Headlight Switch


( Rear defroster switch
J

\ Fan speed control switch
/
X X X X X
O
X X

INHIBITOR SWITCH
X X X X X
O O
X

ENGINE CONTROL UNIT
X
o O O O O o O

\
INPUT

DEVICE

AND
ENGINE

CONTROL

UNIT

OUTPUT
DEVICE
PTC
HEATER

CHOKE

OPENER
(FE
and
F8
—
ECE,
Hong
Kong,
&

Singapore)

COASTING
LEANER
COAST

ENRICHMENT

SOLENOID

VALVE
AIR

BYPASS
SOLENOID
VALVE
IDLE-UP
SOLENOID
VALVE
IGNITION
TIMING
CONTROL
SYSTEM
MAIN
AIR
BLEED
CONTROL
SYSTEM

*
FE
8Valve—Unleaded Fuel:
O
(Related)
General and
FE
12Valve—ECE, Hong Kong, Singapore:
X
(Not related)

76G04A-167
4A—84

4A CONTROL SYSTEM
ENGINE CONTROL UNIT
Check the engine control unit terminal voltages with
a voltmeter.
Caution
a) Warm up the engine before checking the
control unit.
b) If the proper voltage is not obtained, check
the wiring, connections and finally, check
the component.
FE and F8 Engine — ATX (ECE, Hong Kong, and Singapore)
Terminal
(Wire color) Connected to Condition Voltage

1A
(BW)
Ignition switch Ignition switch ON. Battery voltage

m
ST
'-O
Solenoid valve (Main
air
bleed control) Others Battery voltage
m
ST
'-O
Solenoid valve (Main
air
bleed control) Radiator coolant temperature below 17°C (63°F)
or
intake manifold vacuum more than 200 mmHg (7.9 inHg)
Below 1,5V
1C (GO) Solenoid valve (Choke opener) Radiator coolant temperature below 17°C (63°F)
or
during cranking and
27
sec. after engine starts Below 1,5V
Others Battery voltage
1D
(GL)
Air bypass solenoid valve Idle switch OFF and engine speed above approx. 2,100 rpm Below 1,5V
Others Battery voltage
1E
— — —

1F
(G) Solenoid valve (Ignition timing control system)
Radiator coolant temperature above 17°C (63°F),
en-
gine coolant temperature below 72°C (162°F), inhibi-tor switch OFF and engine speed below 2,300
rpm

Below 1.5 V
Others Battery voltage
1G
— — —

1H
(LW) Solenoid valve (A/C) A/C switch
ON
and engine speed below approx. 2,300
rpm

Below 1,5V
Others Battery voltage
11
(YW) Idle-up solenoid valve Inhibitor switch OFF and, headlight switch ON, rear
defroster switch ON, fan speed control switch
is 3rd

or 4th position, A/C operated,
or
engine coolant tem-
perature below 72°C (162°F)
Below 1,5V
Others Battery voltage
1J
(B)
Ground
—
Below 1,5V

9 MSSirSl
ivj
A 1
k *
76G04A-169
4A—86

CONTROL SYSTEM 4 A
Terminal
(Wire color) Connected to Condition Voltage

2A
(YL)
Ignition coil Ignition switch
ON or
engine running Battery voltage
2B (LB) Fan speed control switch Fan speed control switch
in
3rd
or
4th position Below 1.5 V 2B (LB) Fan speed control switch
Fan speed control switch OFF Battery voltage
2C
(BL)
Rear defroster switch Rear defroster switch
ON
Below 1,5V 2C
(BL)
Rear defroster switch
Rear defroster switch OFF Battery voltage
2D
(LG)
A/C switch A/C operated Below 1,5V 2D
(LG)
A/C switch
A/C not operated Battery voltage
2E
(RG)
Headlight switch Headlight switch OFF Below 1.5 V 2E
(RG)
Headlight switch
Headlight switch
ON
Battery voltage
2F
(GW)
Water thermo switch
(Radiator)
Radiator coolant temperature below 17°C (63°F) Below 1.5V 2F
(GW)
Water thermo switch
(Radiator) Radiator coolant temperature above 17°C (63°F) Battery voltage
2G
-— —

2H
(L)
Water thermo switch (In-
take manifold)
Engine coolant temperature below 72°C (162°F) Below 1,5V 2H
(L)
Water thermo switch (In-
take manifold) Engine coolant temperature above 72°C (162°F) Battery voltage
21
(LY)
Vacuum switch Vacuum less than 200 mmHg (7.9 inHg) Below 1.5V 21
(LY)
Vacuum switch
Vacuum more than 200 mmHg (7.9 inHg) Battery voltage
2J (RL) OD release solenoid valve Engine coolant temperature below 72°C (162°F) Below 1.5V 2J (RL) OD release solenoid valve
Engine coolant temperature above 72°C (162°F) Battery voltage
2K
(-)

— — -

2L (BR)
Inhibitor switch "N"
or "P"
range Below 1.5V 2L (BR)
Inhibitor switch
Others Battery voltage
2M (BY) Ignition switch
(START position)
Ignition switch
ON
Below 1,5V 2M (BY) Ignition switch
(START position) Cranking Battery voltage
2N
(LsB) Idle switch Idling Battery voltage 2N
(LsB) Idle switch
Accelerator pedal depressed Below 1,5V

76G04A-170

{ 2M 2K 21
X
2F 2C
2A

2N 2L 2J 2H 2F 2D 2B
(11 X X
1C 1 A^j
1J 1H 1F 1D 1B

FE and F8 Engine — MTX (ECE, Hong Kong, and Singapore)
Terminal (Wire color) Connected to Condition Voltage

A
(RG) Headlight switch Headlight switch
ON
Below 1,5V A
(RG) Headlight switch
Headlight switch OFF Battery voltage
B
(B)
Ground
—
Below 1,5V

4A-87

4A CONTROL SYSTEM
Terminal (Wire color) Connected to Condition Voltage

C (BL) Rear defroster switch Rear defroster switch
ON
Below 1,5V C (BL) Rear defroster switch
Rear defroster switch OFF Battery voltage
D
(LG) A/C switch A/C operated Below 1,5V D
(LG) A/C switch
A/C not operated Battery voltage
E (LY) Solenoid valve (Main
air
bleed control) Intake manifold vacuum more than 300 mmHg (11.8 inHg), and radiator coolant temperature above 17°C (63 °F)
Battery voltage E (LY) Solenoid valve (Main
air
bleed control)
Others Below 1,5V
F
(GW)
Water thermo switch
(Radiator) Radiator coolant temperature below 17°C (63°F) Below 1,5V F
(GW)
Water thermo switch
(Radiator) Radiator coolant temperature above 17°C (63°F) Battery voltage
G (YL)
Ignition coil Ignition switch
ON or
engine running Battery voltage
H
(L)
Water thermo switch (Intake manifold) Engine coolant temperature below 72°C (162°F) Below 1,5V H
(L)
Water thermo switch (Intake manifold) Engine coolant temperature above 72°C (162°F) Battery voltage
J (BW) Ignition switch Ignition switch
ON
Battery voltage
K (GO) Solenoid valve (Choke opener) Radiator temperature below 17°C (63°F)
or
during cranking and
27
sec. after engine starts Below 1,5V K (GO) Solenoid valve (Choke opener)
Others Battery voltage
L (LsB) Idle switch Idling Battery voltage L (LsB) Idle switch
Accelerator pedal depressed Below 1,5V
M
(GL)
Air bypass solenoid valve Idle switch OFF and engine speed above approx. 2,100 rpm Below 1,5V M
(GL)
Air bypass solenoid valve
Others Battery voltage
0
(BY)
Ignition switch
(START position)
Ignition switch
ON
Below 1,5V 0
(BY)
Ignition switch
(START position) Cranking Battery voltage
P
(LW) Solenoid valve (A/C) A/C switch
ON
and engine speed below approx.
2,300
rpm

Below 1,5V P
(LW) Solenoid valve (A/C)
Others Battery voltage
Q (YW) Idle-up solenoid valve Headlight switch ON, rear defroster switch ON,
fan
speed control switch
is
3rd
or
4th position, A/C oper-ated,
or
engine coolant temperature below 72°C (162°F)
Below 1,5V Q (YW) Idle-up solenoid valve
Others Battery voltage
R
(LB)
Fan speed control switch Fan speed control switch
in
3rd
or
4th position Below 1,5V R
(LB)
Fan speed control switch
Fan speed control switch OFF Battery voltage

76G04A-171

f ° O M K I G E C
R P N L J H F D B

4A-88

CONTROL SYSTEM 4 A
FE and F8 Engine — ATX (General)
Terminal (Wire color) Connected to Condition Voltage

1A
(BW)
Ignition switch Ignition switch
ON
Battery voltage
1B (GR) Solenoid valve (Main
air
bleed control) Others Battery voltage 1B (GR) Solenoid valve (Main
air
bleed control) Radiator coolant temperature below 17°C (63°F)
or
intake manifold vacuum more than 200 mmHg (7.9 inHg)
Below 1,5V
1C
— — —

1D
— — —

1E
— — —

1F
— --

1G
-—

1H
(LW) Solenoid valve (A/C) A/C operated Below 1,5V 1H
(LW) Solenoid valve (A/C)
Others Battery voltage
11
(LW) Idle-up solenoid valve Inhibitor switch OFF and, headlight switch ON, rear defroster switch ON, fan speed control switch
is 3rd
or 4th position, A/C operated,
or
engine coolant tem-perature below 72°C (162°F)
Below 1,5V 11
(LW) Idle-up solenoid valve
Others Battery voltage
1J
(B)
Ground
—
Below 1.5V
2A (YL) Ignition coil Ignition switch
ON or
engine running Battery voltage
2B (LB) Fan speed control switch Fan speed control switch
in
3rd
or
4th position Below 1.5V 2B (LB) Fan speed control switch
Fan speed control switch OFF Battery voltage
2C
(BL)
Rear defroster switch Rear defroster switch
ON
Below 1,5V 2C
(BL)
Rear defroster switch
Rear defroster switch OFF Battery voltage
2D
(LG) A/C switch A/C operated Below 1,5V 2D
(LG) A/C switch
A/C not operated Battery voltage
2E
(RG)
Headlight switch Headlight switch
ON
Below 1,5V 2E
(RG)
Headlight switch
Headlight switch OFF Battery voltage
2F
(GW)
Water thermo switch
(Radiator)
Radiator coolant temperature below 17°C (63°F) Below 1.5V 2F
(GW)
Water thermo switch
(Radiator) Radiator coolant temperature above 17°C (63°F) Battery voltage
2G
— — —

2H
(L)
Water thermo switch
(Intake manifold) Engine coolant temperature below 72°C (162°F) Below 1,5V 2H
(L)
Water thermo switch
(Intake manifold) Engine coolant temperature above 72°C (162°F) Battery voltage
21 (LB)
Vacuum switch Vacuum less than 200 mmHg (7.9 inHg) Below 1.5V 21 (LB)
Vacuum switch
Vacuum more than 200 mmHg (7.9 inHg) Battery voltage
2J
(RL)
OD release solenoid Engine coolant temperature below 72°C (162°F) Below 1,5V 2J
(RL)
OD release solenoid
Engine coolant temperature above 72°C (162°F) Battery voltage

4A-89

4A CONTROL SYSTEM
Terminal
(Wire color) Connected to Condition Voltage

2K
— — —

2L
(BR) Inhibitor switch "P"
or "N"
range Below 1,5V 2L
(BR) Inhibitor switch
Others Battery voltage
2M
(BY)
Ignition switch
(START position)
Ignition switch
ON
Below 1,5V 2M
(BY)
Ignition switch
(START position) Cranking Battery voltage
2N
— — —
76G04A-172
(2M X
2
X
2F 2C

X 2L
2J 2H 2F 2D 2B

fll X >< X

1J 1H
>< X
1B

FE and F8 Engine — MTX (General)
Terminal (Wire color) Connected to Condition Voltage

A
(W)
Headlight switch Headlight switch
ON
Below 1,5V A
(W)
Headlight switch
Headlight switch OFF Battery voltage
B
(B)
Ground
—
Below 1,5V
C
(BL) Rear defroster switch Rear defroster switch
ON
Below 1,5V C
(BL) Rear defroster switch
Rear defroster switch OFF Battery voltage
D
(LG) A/C switch A/C operated Below 1.5V D
(LG) A/C switch
A/C not operated Battery voltage
E
(LB) Solenoid valve (Main
air

bleed control)
Intake manifold vacuum more than 300 mmHg (11.8 inHg), and radiator coolant temperature above 17°C (63 °F)
Battery voltage E
(LB) Solenoid valve (Main
air

bleed control)
Others Below 1.5V
F
(GW)
Water thermo switch
(Radiator)
Radiator coolant temperature below 17°C (63°F) Below 1,5V F
(GW)
Water thermo switch
(Radiator) Radiator coolant temperature above 17°C (63°F) Battery voltage
G (YL)
Ignition coil Ignition switch
ON or
engine running Battery voltage
H
(L)
Water thermo switch (Intake manifold) Engine coolant temperature below 72°C (162°F) Below 1,5V H
(L)
Water thermo switch (Intake manifold) Engine coolant temperature above 72°C (162°F) Battery voltage
I
— — —

J
(BW)
Ignition switch Ignition switch
ON
Battery voltage
K
— —

L
— — —

M
— — —

N
— —
4A-90

CONTROL SYSTEM 4A
WATER THERMO SWITCH (RADIATOR)
Inspection
1. Remove the switch from the radiator.
2. Place the switch in water with a thermometer and
gradually heat the water.
3. Check for continuity of the switch with an
ohmmeter.

Coolant temp. Continuity
More than approx.
17°C (63°F)
Yes
Less than approx.
17°C (63°F)
No

76G04A-183
4. If not as specified, replace the water thermo switch.
Note
a) Apply sealing tape to the threads of the
switch before installing it.
b) After installation, check the coolant level
and check for leaks.
76g04a-184
WATER THERMO SWITCH (INTAKE MANIFOLD)
Inspection
1. Remove the switch from the intake manifold.
2. Place the switch in water with a thermometer and
gradually heat the water.
3. Check for continuity of the switch with an
ohmmeter.

Coolant temp. Continuity
More than approx.
72°C (162°F)
Yes
Less than approx.
72°C (162°F)
No

76G04A-185 4. If not as specified, replace the water thermo switch.
Note
a) Apply sealing tape to the threads of the
switch before installing it.

b)
After installation, check the coolant level
and check for leaks.
76G04A-186
4A-95

FUEL SYSTEM 4B
COMPONENT DESCRIPTIONS
Component Function Remarks
Air flow meter
Detects amount
of
intake
air;

sends signal
to
engine control unit Intake
air
thermo sensor and fuel pump
switch
are
integrated

Atmospheric pressure sensor
Detects atmospheric pressure; sends sig-nal
to
engine control unit

Circuit opening relay
Voltage
for
fuel pump while engine running

Clutch switch
Detects in-gear condition; sends signal
to
engine control unit Switch
ON
when clutch pedal released

Engine control unit
Detects signals from input sensors and switches; controls injector operation

Fuel filter
Filters particles from fuel

Fuel pump
Provides fuel
to
injectors • Operates while engine running
• Installed
in
fuel tank

Idle switch
Detects when throttle valve fully closed;
sends signal
to
engine control unit
Installed
in
throttle sensor

Ignition coil (-) terminal
Detects engine speed; sends signal
to
engine control unit

Ignition switch (ST position)
Sends engine cranking signal
to
engine control unit

Inhibitor switch
Detects in-gear condition; sends signal
to
engine control unit
Switch
ON in "N" or "P"
range

Injector
Injects fuel into intake port • Controlled
by
signals from engine control unit • High-ohmic injector

Intake air thermo sensor
Detects intake
air
temperature;
sends signal
to
engine control unit Installed
in air
flow meter

Main relay
Supplies electric current
to
injectors and engine control unit

Neutral switch
Detects in-gear condition; sends signal
to
engine control unit
Switch
ON
in-gear

Oxygen sensor
Detects Oxygen concentration; sends sig-nal
to
engine control unit
Zirconia ceramic and platinum coating

Pressure regulator
Adjusts fuel pressure supplied
to
injectors

Pulsation damper
Absorbs fuel pulsation

Throttle sensor
Detects throttle valve opening angle; sends signal
to
engine control unit
Integrated idle switch

Water thermo sensor
Detects coolant temperature;
sends signal
to
engine control unit

Water thermo switch
Detects radiator coolant temperature; sends signal
to
engine control unit ON: above 17°C (63°F)

76G04B-058
4B—43

DECELERATION CONTROL SYSTEM 4B
COMPONENT DESCRIPTIONS
Component Function Remarks
Brake light switch Detects braking operation (deceleration);
sends signal to engine control unit
Clutch switch Detects in-gear condition;
sends signal to engine control unit Switch ON when clutch pedal released
Dashpot (MTX) Prevents sudden closing of throttle valve during deceleration or shifting Adjustment speed: 1,900—2,100 rpm
Engine control unit Detects signals from input sensors and switches; cuts fuel injection
Idle switch Detects when throttle valve fully closed; sends signal to engine control unit Installed in throttle sensor
Ignition coil (-) terminal Detects engine speed; sends signal to engine control unit
Neutral switch Detects in-gear condition; sends signal to engine control unit Switch ON when in-gear
Water thermo sensor Detects coolant temperature; sends signal to engine control unit
Water thermo switch Detects radiator coolant temperature; sends signal to engine control unit ON: above 17°C (63°F)
76G04B-089
4B—65