1987 MAZDA 626 fuel pump relay

4C FUEL SYSTEM
86U04A-078
76G04C-097
76G04C-098
„\W cLTest connector (Yellow)
'-/jumper wire \\ \ •
5. Disconnect the vacuum hose from pressure regu-
lator, and place a finger over the end of the hose.
6. Check the fuel line pressure.
Fuel line pressure: 235—275 kPa
(2.4—2.8 kg/cm2, 34—40 psi)
7. If not within specification, replace the pressure
regulator.
8. Connect the vacuum hose to pressure regulator.
FUEL PUMP
Operation Test
1. Connect a jumper wire to the test connector
(Yellow).
2. Remove the fuel filler cap.
3. Disconnect transfer pump connector (8-pin).
4. Turn the ignition switch ON.
5. Listen for operational sound of the fuel pump at
the filler inlet.
6. Install the fuel filler cap.
7. If no sound was heard, check the voltage at the
fuel pump connector (WY wire and a ground).
Voltage: 12V
8. If the voltage is normal, replace the fuel pump.
9. If not correct, check the control relay and circuit
(Refer to page 4C—96.)
10. Disconnect the jumper wire.
Volume Test
Warning
Before performing the following procedures,
release the fuel pressure from the fuel system
to reduce the possibility of injury or fire.
(Refer to page 4C—52)
1. Connect a jumper wire to test connector (Yellow).
2. Disconnect the fuel return hose from fuel return
pipe.
76G04C-099
4C-56

4C CONTROL SYSTEM
RELATIONSHIP CHART
Output Devices
and
Input Devices (Unleaded fuel)
IGNITION SWITCH
(ON POSION) X X X X X O X X X X X X X X O
TEST CONNECTOR X X X O X X X X X X X X X O X
ELECTRICAL LOAD CONTROL UNIT X X X o X X X X X X X X X X X
P/S PRESSURE SWITCH X X X o X X X X X X X X X X X
A/C SWITCH X X X o X X X X X X X X O X X
IGNITION SWITCH
(STA POSITION) O O X o O X X X X O X X X O X
NEUTRAL
AND

CLUTCH SWITCH O X X o X X X X X X X X X X X
OXYGEN SENSOR o X X X X X X X X X X X X X X
WATER THERMO
SWITCH (RADIATOR) o X X X X X X X o X X X X X X
INTAKE
AIR

THERMO SENSOR X X X X X X X X X O X X X X X
WATER
THERMO SENSOR o X X o X X o o O O X X X O o
IDLE SWITCH o X X o X X X X X o X X X O X
THROTTLE SENSOR o X X X X X X X O X X X X o X
AIR FLOW SENSOR o X X X X X X o X X X X X o O
Ne SIGNAL o o X O o X X O O O o o X o O
G SIGNAL X O X X X X X X X X X X X X X

\
INPUT

DEVICE
OUTPUT
DEVICE
FUEL
INJECTION
AMOUNT FUEL

INJECTION

TIMING
AIR
VALVE

ISC
VALVE
FUEL
PUMP

CONTROL
MAIN
POWER
CONTROL
SOLENOID
VALVE
(No.1
PURGE)
SOLENOID
VALVE
(No.2
PURGE)
SOLENOID
VALVE
(EGR)
SOLENOID

VALVE

(PRESSURE

REGULATOR
CONTROL)
SOLENOID
VALVE

(VARIABLE

INERTIA
CONTROL)

OXYGEN

SENSOR
RELAY
I A/C

RELAY

IGNITER
AIR

FLOW
SENSOR
(BURN-OFF)
\
INPUT

DEVICE
OUTPUT
DEVICE
INJECTOR
BAC
VALVE

CONTROL
RELAY
SOLENOID
VALVE
(No.1
PURGE)
SOLENOID
VALVE
(No.2
PURGE)
SOLENOID
VALVE
(EGR)
SOLENOID

VALVE

(PRESSURE

REGULATOR
CONTROL)
SOLENOID
VALVE

(VARIABLE

INERTIA
CONTROL)

OXYGEN

SENSOR
RELAY
I A/C

RELAY

IGNITER
AIR

FLOW
SENSOR
(BURN-OFF)

76G04C-167
4C—92

CONTROL SYSTEM 4C
Output Devices and In put Devices (Leaded fuel)
IGNITION SWITCH
(ON POSITION) X X X X X O X X X X O
TEST CONNECTOR X X X O X X X X X O X
KNOCK SENSOR X X X X X X X X X o X
ELECTRICAL LOAD
CONTROL UNIT X X X O X X X X X X X
P/S PRESSURE SWITCH X X X o X X X X X X X
A/C SWITCH X X X o X X X X O X X
IGNITION SWITCH (STA POSITION) O O X o O X O X X O X
NEUTRAL AND
CLUTCH SWITCH O X X o X X X X X X X
INTAKE AIR THERMO SENSOR X X X X X X O X X X X
WATER THERMO SENSOR O X X o X X O X X O o
IDLE SWITCH o X X o X X o X X O X
VARIABLE RESISTOR (IN AIR FLOW SENSOR) o X X X X X X X X X X
AIR FLOW SENSOR o X X X X X X X X O O
Ne SIGNAL o o X O o X O o X o O
G SIGNAL X O X X X X X X X X X

INPUT

DEVICE

OUTPUT

DEVICE

FUEL

INJECTION

AMOUNT
FUEL

INJECTION

TIMING
AIR
VALVE
ISC

VALVE

FUEL

PUMP

CONTROL
MAIN

POWER

CONTROL

SOLENOID

VALVE

(PRESSURE

REGULATOR

CONTROL)

SOLENOID

VALVE

(VARIABLE

INERTIA

CONTROL)

A/C
RELAY

IGNITER
AIR

FLOW

SENSOR

(BURN-OFF)

INPUT

DEVICE

OUTPUT

DEVICE

INJECTOR
BAC

VALVE

CONTROL
RELAY
SOLENOID

VALVE

(PRESSURE

REGULATOR

CONTROL)

SOLENOID

VALVE

(VARIABLE

INERTIA

CONTROL)

A/C
RELAY

IGNITER
AIR

FLOW

SENSOR

(BURN-OFF)

76G04C-168
4C—93

4C CONTROL SYSTEM
Output Devices
and
Engine Conditions (Unleaded fuel)

REMARK

*
Above

7,000

rpm:

fuel

cut

'Coolant

temp.:
below

50°C

(122°F)

41 Coolant
temp:

below

70°C

(158°F)

*2 Engine
speed
above
1,700
rpm
*3 Engine

speed:

1,500—3,500

rpm

*
During
hot

start

only

*
Engine
speed:
above

5,200

rpm

'Engine

speed:
above

3,000

rpm

'Delays

0.5
second

IGN:

ON

(ENGINE
NOT RUNNING)

No

injection

No bypass OFF
(main

fuel

pump

not
operated)
OFF
OFF
z
1

IDLE

(THROTTLE
VALVE
FULLY CLOSED)
Rich

and

i
lean
Sequential
(once

per

two

revolutions)
OFF

o en C3 UJ
z
"After

start-
ing:

ON

(Vacuum

cut) OFF
o

DECELE-
RATION
'Fuel

cut

L

Small
amount
of
bypass
air
N (1st
stage
operate:

o
o Ho 3 O CO CD > CO >
>; CO
CO c o
c o o

HEAVY
LOAD
•ST c
Closed

Small
amount
of
bypass
air

-co-CD CO
N (1st
stage
operate:

In CD 2? 03 a. o CD o> CO to "O c

*3 OFF (EGR)

o Ho 3 O CO CD > CO >
03 k-o CO c 03 CO z o *
CD c O) c 03 c o
c o o a 3

ACCELE-
RATION
Rich

o •*—• 3 o > CD
O

Small
amount
of
bypass
air

03 Q. O Q. E 3

ON

O
In CD 2? 03 a. o CD o> CO to "O c
ON
(EGR cut)
:F (Vacuum
to
pressure

regulatt

03 3 -C CO o
c 03 CS3 > X o o
z o * CO •o c CD Q. CD T3
C CO CD o "O 3= O c: 3 CO
LL LL o

MEDIUM
LOAD
WARM
Rich

and lean

|
Q. CD O
CD D
C CO E
CVJ.
z o fS *
*3 OFF (EGR)
:F (Vacuum
to
pressure

regulatt

E 3 3
c 03 i t 3 G, LL LL
T3 CD O c CO > "O <
C CO CD o "O 3= O c: 3 CO
LL LL o

MEDIUM
LOAD

COLD

ro
c CD 3 cr
z O "a CD a? CD CL o

F (2nd
stage
not
operated)
:F (Vacuum
to
pressure

regulatt

z o * O «

WARMING
UP

(DURING
IDLE)
Rich

CD CO c CD Q-O
o
c 3 CO O CO E CO
o c F (2nd
stage
not
operated)

tr O UJ
z o
O
LL z
Fixed

at

BTDC

12°

CRANKING
(COLD
ENGINE)
1
group
(twice

per

revolution)

CO
«
CD urn i CO
CO
LL LL O
LL O * « o o
LL LL o
Fixed
at

BTDC

6°

z o

SOLENOID
VALVE
(PRESSURE
REGU-

LATOR

CONTROL)

CC
o z o o iii z
o z 111

OUTPUT
DEVICE
FUEL

INJECTION

AMOUNT FUEL
INJECTION
TIMING
AIR

VALVE

'
ISC

VALVE
FUEL
PUMP

CONTROL
MAIN
POWER
CONTROL
SOLENOID
VALVE
(No.1
PURGE)
SOLENOID

VALVE

(NO.2

PURGE)
SOLENOID
VALVE
(EGR)
SOLENOID
VALVE
(PRESSURE
REGU-

LATOR

CONTROL)
SOLENOID
VALVE
(VARIABLE
INE
TIA
CONTROL)

> <
Ul oc oc o
£T u. O 1 z oc 3 m
oc o

OUTPUT
DEVICE
INJECTOR
BAC
VALVE
CONTROL
RELAY
SOLENOID
VALVE
(No.1
PURGE)
SOLENOID

VALVE

(NO.2

PURGE)
SOLENOID
VALVE
(EGR)
SOLENOID
VALVE
(PRESSURE
REGU-

LATOR

CONTROL)
SOLENOID
VALVE
(VARIABLE
INE
TIA
CONTROL)

tn z Ul (0 z Ul o >-X o
A/C

RELAY

IGNITER

z Ul (O
=5 o
IL oc <
76G04C-169
4C—94

CONTROL SYSTEM
4C

Output Devices
and
Engine Conditions (Leaded fuel)

REMARK

E Q
O O O r-»" CD > o n <

fuel
cut

'Coolant

temp.:

below

50°

(122°F)

*
During

hot
starting
only

*
Engine

speed:

above

5,400

rpm

'Delays

0.5

seconds

IGN:
ON
(ENGINE
I
NOT
RUNNING)

o
z
injection
No
bypass
OFF

(main

fuel

pump

not
operated)
OFF
LL
I

IDLE
(THROTTLE
VALVE
FULLY
CLOSED)
Rich

I
Sequential (once
per
two

revolutions)
"After

start-
ing:
ON

(vacuum

cut)
O

DECELE-
RATION

i

i
'Fuel

cut

•o CD CO "co" CD ts o to 3 o CO CD > CO
CO c o
c o o

HEAVY
LOAD
sz "co" c
O o CO CO CO Q. >. -O
O
CD Q. O CL E CL ® D
C CO F
o 08 3 u> £ CD 3 CO 0) CD
o to 3 o CO CD > CO
z

c o o c
B

ACCELE-RATION

ir o 3 0 > CD 1 O
C
O E CO
"CO
CD Q. O CL E CL ® D
C CO F
z

o 08 3 u> £ CD 3 CO 0) CD
CD e 3 SZ CO o
O * CO
c CD CL CD T3
c CO 8 "D

'
MEDIUM
LOAD
WARM
Normal

CD Q. CD O
E CO
z
O
o o_ O
E
3 3
o CO ^ LL LL O
E 3 3 O CO
•o "O <
c
3
m
LL LL o

'
MEDIUM
LOAD
COLD

.H C CD 3 CT
o_ O
E
3 3
o CO ^ LL LL O

z
o *

WARMING
UP

(DURING
IDLE)
Rich

CD CO

*Open

B
3
CO
O
CO
E
<®
LL
Fixed

at
BTDC
12°

CRANKING
(COLD
ENGINE)
1
group
(twice

per

revolution)

CO
«
0)
>,
u>n w-CO
o

OFF
Fixed

at

BTDC

6°
ENGINE
CONDITION
OUTPUT
DEVICE
FUEL
INJECTION

AMOUNT
'
FUEL
INJECTION

TIMING
AIR

VALVE
ISC
VALVE
FUEL
PUMP
CONTROL MAIN
POWER
CONTROL
SOLENOID
VALVE
(PRESSURE
REGU-

LATOR

CONTROL)
SOLENOID
VALVE
(VARIABLE
INER-
TIA
CONTROL)

(T ik 0 1 z DC 3
ffl

OC o tn

OUTPUT
DEVICE
INJECTOR
BAC
VALVE
CONTROL
RELAY
SOLENOID
VALVE
(PRESSURE
REGU-

LATOR

CONTROL)
SOLENOID
VALVE
(VARIABLE
INER-
TIA
CONTROL)

A/C

RELAY

IGNITER

Z Ul tn
£ o
ik DC <
76G04C-170
4C—95

4C CONTROL SYSTEM
EGI MAIN FUSE
Inspection
Check the continuity of EGI main fuse.
69G04A-161
CONTROL RELAY
Power Supply Circuit
1. Check that a "clicking" sound is heard at the con-
trol relay when turning the ignition switch ON and
OFF.
Note
The control relay is located under the center
console.
76G04C-171
2. Apply 12V to the 2B terminal and ground the 2D
terminal of the control relay.
3. Check voltage at the terminals with an voltmeter.
terminal
Terminals Grounded Not grounded
2C 12V OV
2E 12V OV
76G04C-172
From EGI From '9' From Ig. main fuse switch (ON) / switch
(ST)
To C/U / 9round To main To injector fuel Pump
Fuel Pump Circuit
1. Apply 12V and a ground to the terminals described
below and check the terminals with an ohmmeter
or voltmeter.
Terminal applied 12V
Terminal
grounded
Terminal checked
Correct condition
1B 1D 2F-1A Continuity
2F 1C 1A ADDrox.12V
76G04C-173
4C-96

4C CONTROL SYSTEM
Terminal Input Output Connection to Voltage (After warming-up) Remark Terminal Input Output Connection to Ign: ON Idle Remark
10 o Air flow sensor
(Burn-off control) Below 2.5V White burning off:
Approx. 8—12V
1P o
Control relay (Power supply circuit) Below 2.5V Ignition switch OFF:
Approx. 12V
1Q 0 Control relay (Fuel pump circuit) Approx. 12V Below 2.5V
1R
(L/F) O Knock sensor OV or 2—7V While knocking:
Approx. 0.001
1S — — — — —
1T o Ignition switch
(ON position) Approx. 12V
1U — — — — —
1V — — — — —
1W o Test connector Test connector grounded: OV Test connector not grounded: approx. 12V Green connector, 1-pin
1X o Igniter Approx. 12V *Approx.1V 'Engine Signal
Monitor: green and
red lights flash
2A (U/F) o V ref 4.5—5.5V
2B o Air flow sensor
(Ground) OV
2C — — Ground (E2) OV
2D (U/F) o Oxygen sensor OV 0-1.0V
• Cold engine: 0V at idle
• After warming-up: Increase engine speed: 0.7—1.0V Deceleration: 0—0.2V
2E o Air flow sensor
(Intake air mass) 1.0—1.6V 1.7—2.3V Increase engine speed: voltage increases
2F — — — .— —
2G (U/F) o Throttle sensor Accelerator pedal released: approx. 0.5V
Max. voltage (Throt-tle valve fully opened): approx. ,4.3V
2H (L/F) o Air flow sensor (Variable resister) 0-5V Depends on
adjustment
21 o Water thermo sensor Approx. 0.4V
Engine coolant
temp. 20°C (68°F):
approx. 2.5
2J o Intake air thermo sensor (Dynamic chamber)
Approx. 2.5V at 20°C (68°F)
2K o
Solenoid valve (Pressure regula-tor control)
For 120 sec. after ignition switch OFF - ON: below 2.5V
For 120. sec after starting: below 2.5V
During hot condi-tion: Coolant temp, above 70°C (158°F) Intake air temp, above 30°C (86°F) ...Unleaded fuel above 50°C (122°F) ...Leaded fuel
2K o
Solenoid valve (Pressure regula-tor control)
ADDrox. 12V Other conditions
2L — — — — —
Note
a) Terminal labeled "U/F" are only for unleaded fuel.
b)Terminal labeled "L/F" are only for leaded fuel.
4C-100

30 TECHNICAL DATA
4B. FUEL AND EMISSION CONTROL SYSTEMS (FUEL INJECTION FE)
Item Specifications

Fuel tank capacity Liters (US gal, Imp gal) 60 (15.9, 13.2)
Fuel pump
Type In-tank, electric motor
Fuel pump Fuel pressure kPa (kg/cm2, psi) 441-588 (4.5-6.0, 64-85) Fuel pump
Feeding capacity cc (cu in)/10 sec. 220 (13.4) min.
Air cleaner Element type Oil permeated
Accelerator cable Deflection
mm
(in) 1—3 (0.04-0.12)
Idle speed
rpm
ATX: 800 +58 (Neutral), ATX: 900 +600
(P
range)
Dash
pot
Adjustment speed
rpm
1,900-2.100
EGR control valve Starts
to
open mmHg (in Hg) 40-60 (1.6-2.4)
Air control valve Starts
to
open mmHg (in Hg) 180-280 (7.1-11)
Water thermo valve Opened
°C
(°F) Higher than 46—54 (115-129)
Water thermo switch Opened
At
radiator
°C
(°F) Lower than 15—19 (59—66)
Vacuum switch valve Starts to open mmHg (in Hg) 66—106 (2.6—4.2)
Water thermo sensor Resistance
-20°C (-4°F)k!) 14.5-17.8
Water thermo sensor Resistance 20°C (68°F)
kQ
2.2-2.7 Water thermo sensor Resistance
80°C (176°F)k!i 0.28-0.35
Throttle sensor
Resistance
at

fully closed
B
C kQ
4-6
Throttle sensor
Resistance
at

fully closed A
« B Q
Approx.
500

Throttle sensor Resistance
at
fully opened A
«• B kQ
Approx.
4.5
Throttle sensor
Setting Closed at mm (in) 0.4 (0.0157)
Throttle sensor
Setting Open at mm (in) 0.55 (0.022)
Air flow meter
Resistance
of

full closed

E2 « Vs fi
More than
20

Air flow meter
Resistance
of

full closed

E2 •+ Vc 0
100-300
Air flow meter
Resistance
of

full closed
E2 VB Q
200-400 Air flow meter
Resistance
of

full closed
Ei
•+ Fc Q OO
Air flow meter
Resistance
at
full open Ei
•+ Fc Q
0
Intake
air
thermo sensor Resistance
-20°C M°RkQ 13.6-18.4
Intake
air
thermo sensor Resistance 20°C (68°F) kfi 2.21—2.69 Intake
air
thermo sensor Resistance
60°C (140°RkQ 0.493-0.667
Pressure regulator Regulating pressure At idling kPa
(kg/cm
,
psi) 235-275 (2.4—2.8, 34-40)
Injector
Injection amount cc (cu in)/15 sec. 38-53 (2.3-3.2) Injector
Resistance
Q
12-16
Circuit opening relay Resistance STA Ei Q 15-30 Circuit opening relay Resistance B
Fc fi
80-150
Fuel Unleaded gasoline

30-20