fuel pump MAZDA 323 1992 Suplement User Guide

TROUBLESHOOTING GUlDE F3
STEP INSPECTION ACTlON
4
Is there buttery voltage at fuel pump connector Yes
* (G/R) with lgnitron switch ON and F/P terminal Check contmurty of fuel pump
between termrnafs G/R and 8
Check ctrcutt openmg relay
5
Is qector operating sound heard whtle engine IS Yes Go to Step 8
being cranked?
No Go to next step
CcI page F3-45
+ If 0K;check for a short cjrcult rn
wiring harness
(Injector reastor-Injector)
=D If not OK, replace Injector reststor
fuel Line pressure: 265-314 kPa
12.7-3.2 kgflcd, 38-46
psi)
if fuel return hose is clogged or
t, replace pressure
CT psge F3-3
F3-2 3

TROUBLESHOOTING GUIDE F3
4 CRANKS NORMALLY 8UT WILL NOT START (PARTfAL COMBUSTION) - AFTER WARM-UP
&RIP-
l Engine cranks at nurmal speed and shows partial combustion but will not Continue running after being hot
soaked
FION
l Battery in normal condltlon
*Engine starts normally when cold
TROUBLESHOOTING
HINTS] 3 Air/Fuel mixture too rich @ Vaporlock
ssure not held in fuel line after engrne IS
GND mth jumper wire tor 3
minutes with ignition
Fuel
line pressure: 265-314 kPs (2.7-3.2 kgflcm2, 38-46 psi 1
c3 If pressure
quickly increases,
check pressure regulator
4 If pressure
gradually increases,
check fuel line and filter lor
clogging
If hose is not clogged. check fuel
pump maximum pressure
High pressure Check if fuel return hose is clogged or
restricted
INSTALL CLAMPS e If rt is not, replace pressure
regulator
@ It It 6. repalr or replace it CT page F3-3
F3-25

F3 TROUBLESHOOTING GUIDE
I- STEP lNSPECTlON ACTION
Yes Go to Step 8
5 In same condition as in Step 2, IS fuel ilne pres-
sfire held after Igrxtbon swatch rs turned OFF?
Fuel line pressure: More than 147 kPa
Il.5 kgflcm’, 21 Psi 1 for 5 min.
6 In same condition as in Step 3, IS fuel line pres-
sure held after lgnltron switch IS turned OFF?
Fuel line pressure: More than 147 kPa
{ t.5 kgf/cm*, 21 psi) for 5 min.
No
I Go to next step
Plug both vcuum ports of pressure regulator; IS
fuel lme pressure held after ignltlon switch is
turned OFF? Yes Replace pressure regulator
r~ page F3-3
Fuel line pressure: More than 147 kPa
{ 1.5 kgf/crn*, 21 psi] for 5 min.
NO Check fuel pump hold pressure
e If OK, check InJector for fuel
leakage
e If not OK reptace fuel pump ZF- page F3-42
T page F3-3
8 Dlscofinect water thermosensor connector, does
engtne start? Yes Check water thermosensor
e ff OK. check connectrons of water
thermosensor and ECU 2Q terminal
Q If not OK, replace water thermo-
sensor
ET page F3-13
No 1 Go to next step --~
Is “00” drsplayea on Self-Diagnosis Checker
with ignition switch ON? 9 Yes Go to next step
NO Service Code No. displayed
Check for cause (Refer to specified
check sequence)
c7 page F3-16 SYSTEM SELECT, 1
“88” flashes
Check ECU terminal IF voltage
KIT page F3-45
Voltage: Battery voltage
(ignition switch ON)
e If OK, replace ECU
ET- page F3-2
e If not OK, check wiring
(ECU - Self-Diagnosis Checker)
Y %EtECT SW: A
Yes 1 Go to next step 10 Are rf ECU termrnaf voltages are OK?
(especjaffy 1C. 2D. and 2Q)
CT page F3-45
NO Check for cause
Yes Replace ECU
=T page F3-2
No Change to another brand of fuel
13EOF3 331 Try known good ECU, does condition improve?
CT page F3-2
F3-26

F3 TROU8LESliOOTING GUIDE
iTEP INSPECTION
ACTtUN
5 Run engine at idle; is fuel line pressure held af-
Yes Go to next step
ter ignition switch is turned OFF?
Fuet Ijne pressure: More than 147 kPa No Plug both vacuum potts of pressure
{1,5 kgflcd, 21 pdf for 5 min. regulator;
and check if fuel line pres-
sure is held after ignition switch is
turned OFF
NSTAtl CLAMPS 4 If it is, replace pressure regulator
c3 If it is not, check fuel pump hold CT page F3-3
pressure
If fuel pump is OK, check injectors
for fuet leakage
CT- page F3-4
6 Warm up engine to normal operating tempera-
Yes
ture and stop it Change to another brand of fuel
Connect diagnosis connector terminals F/P and
GND with jumper wire for 3 minutes with rgnitlon
switch ON; does engine start easily?
No Go to next step
7 Try known good ECU; does condition improve?
Yes Replace ECU
CT page F3-3 w- page F3-3
No Change to another brand of fuel
t3EOF3
F3-28

F3 TROUBLESHUOTING GUIDE
TEPI tNSPECTION ACflON
e If OK, replace injector
4 If not OK, check for cause w Section 82
(Upper vacuum hose to pressure regulator 4
If pressure quickly increases,
check pressure regulator
4 If pressure
gradually increases,
check for clogging between fuel
pump and pressure regulator
if hose is not clogged, check fuel
pump maximum pressure
I
12 Is engine compression correct? Yes Go to next step w Sectlon 82
Engine
compression: 1059 kPa (10.8 kgf/cm2, 152 psi]-300 rpm NO Check for cause w Section B2.
13 Connect System Selector to diagnosis connector
Yes Try known good ECU; does condition
and $et Test Switch to SELF TEST; is ignition improves? w page f3-3 timing correct at idle after warm-up?
ignition timing (BTDC): 10 * to
NO Adjust ignition timing
F3-30
7
*
10
DES&
HON
-*
ITEP
2
3
4

F3 TROUBLESHOOTING GUIDE
3TEI ACTION
Is fuel line pressure correct at Idle?
*
Fuel line pressure: 265-314 kPa
12.7-3.2 kgf/cm’, 38-46 psi]
(Two vacuums hose to pressure regulator
disconnected)
304-392 kPa [ 3.1-4.0 kgf/cm’, 44-57 psi 1
(Upper vacuum hose to pressure regulator
disconnected)
INSTALL CLAMPS Yes Go to next step
No Low pressure
Check fuel line pressure while pinching
fuel return hose
4 If pressure quickly Increases,
check pressure regulator
e If pressure gradually Increases,
check for clogging between fuel
pump and pressure regulator
If hose is not clogged, check fuel
pump maxrmum pressure
Connect System Selector to diagnosis connector
and set Test Switch to SELF TEST; is ignition
tlmlng at idle correct after warm-up?
Ignition timing (BTDC): 10 f lo Yes Go to next step
No Adjust tgnrtkon system
8 Dtsconnect water thermosensor connector; does
engine condrtlon Improve? Yes Replace water thermosensor
No
Try known good ECU. does condltlon
Improve?
w page F3-13
Go to next step
Check if injector resistance is OK
w page F3-42 9 Is jqector operating sound heard at Idle?
Yes
No
Resistance: Approx. 2.11 Q
(at 20°C 168*F])
4 If it is, check wlnng
(ECU - Injector)
c3 If it Is not, replace injector
Go to next step IO
Yes Is engine compressron cprrect?
w Section G
No
Engine compression:
1059 kPa 110.8 kgf/cm2, 152 psi)-300 rDm
is strong blue spark vrslble at each disconnected
hrgh-tension lead?’ Check engine
3 Section B2
17
Yes Go to next step
No Check high-tension lead
w Section G
c3 If UK, check distrrbutor cap and
rotor
3 If not OK, replace htgh-tensron lead
Try known good ‘ECU: does condrtron
Improve7
w page F3-3 12 Are spark plugs.OK?
w Section G
l Wear and carbon butld up l Piug gap l Damage Yes
NO
Clean, adjust
13EOi3.334
F3-32.

F3 FUEL SYSTEM
t 3EoF3-344
1
FUEL SYSTEM
FUEL PUMP
inspection
Fuel pump operation
1. Connect the diagnosis connector F/P and GND terminals
by using a jumper wire.
2. Remove the fuel filler cap.
3. Turn ON the ignition switch.
4.
Listen at the filler inlet for the operational sou.nd of the fuel
pump.
5. Install the fuel filler cap.
6. If no sound is heard, measure the voltage between the fuel
pump connector (G/R) to a ground.
Voltage: 8attey vo kage
7. If not as specified, check the circuit opening relay and circuit.
8. ff as specified, check fur continuity between fuel pump con-
nector (G/R) and (B).
9. If there is continuity, reptace the fuel pump.
10. If there is no continuity, repair the ground circuit.
f3EOF3.345
13EOF3-346 FUEL PUMP RESlSTORlRELAY
System Operation
1. Remove the rear seat cushion.
2. Measure the voltage at the fuel pump connector terminal
A (G/R).
Voltage
I
Cranking
1 Battery voltage
Ignition switch ON ov 3. If not as specified, perform the following inspections, and
repair or replace as necessary.
l Fuel pump resistor/relay resistance
(Refer to page F3-41.)
l ECU 11 terminal voltage (Refer to page F3-45.)
l Wiring harness and connector
F3-40
ii e -
*
_~ --
C --
A-'

-,
-,
--
--
-1
E
7
2
I
i 3EAR SE
--

FUEL SYSTEM F3
13EOF3.34
c I 13EOF3-364 FUEL PUMP CONNECTOR
/
!NSTALL CLAMPS
I
l nspection
1, Disconnect the resistor/relay connector.
2. Ground the fuel pump resistor relay terminal D.
3. Apply battery voltage and check for continuity as shown.
Terminal C
Continuity between A and I3
Battery voltage applied NO
ov Yes
4. Measure the resistance between terminals E and F.
Resistance : 0.38--0.42Q (at 2O*C {6S°F 1)
PRESSURE REGULATOR
Inspection
Fuel line pressure
Warning
l Before performing the following operation, release
the fuel pressure from the fuel system to reduce the
possibility of injury or fire. (Refer to page F3-21.)
1. Disconnect the negative battery terminal.
2. Connect a fuel pressure gauge between the fuel filter and
the fuel main hose. (install clamps as shown.) , .
I
3. Connect the negative battery terminal.
/t.
4, Start the engine and run it at idle.
5. Measure the fuel line pressure.
Fuel line pressure:
206-255 kPa [ 2.1-2.6 kgflcml, 30-37 psi )
6. Disconnect the upper vacuum hose from the pressure regu-
lator and measure the fuel line pressure.
Fuel line pressure:
304-392 kPa (3.1-4.0 kgf/cm2, 44-57 psi )
F3-41

F3 CONTROL SYSTEM
Terminal voltage
Reference date
Vs: Battery voltage
‘em&al Input Output Connected to Test condition Correct voltage Remark
1A - - Battery Constant VB
For backup
18 0 Main relay
Ignition switch OFF ov
(FUEL INJ relay) -
ON
V8
1C 0 lgnitlon switch While cranking Approx. 1 OV
(START) -
Ignition switch ON ov
10 0 Self-Diagnosis Test switch at SELF TEST
Wtth Self-
Checker Lamp illuminated for 3 sec. after ignition Approx. 5V
(monitor lamp) switch OFFdON Diagnosis Check-
er and System
lamp not iltuminated after 3 sec. V8 Selector
Test switch at 02 MONITOR with engine
idling Approx. 5V
Monitor lamp illuminated
Test switch at 02 MONITOR with engine
idling Vi3
Monitor lamp not illuminated
IE - - - - - -
IF
0 Self-Diagnosis Buzzer sounded for 3 sec. after ignition
Below 2SV
l With Seif-
Checker switch OFF-+ON
Diagnosis
(service code)
Buzzer not sounded after 3 set V0 ’ Checker and
Buzzer sounded Below 2.5V System Selector
l With System
Buzzer not sounded VB Selector test
switch at SELF
TEST
1G 0 igniter tgnition switch ON
ov
-
Idte
Approx. 0.2V
It-l 0
Solenoid valve Ignition switch ON
VB
(wastegate)
Idle
Approx. 2V ’ -
II
0 Fuel pump While cranking
Approx. 1 OV
resistor/relay -
Idle
8etow 1.5V
IJ 0 NC relay Ignition switch ON
VB
A/C switch UN at idle
Below 2.5V
. NC switch OFF at idle V3
-
IK 0 Diagnosis
connector
(TEN terminal) System Selector test switch at
02 MONITOR
System Selector test switch at
SELF TEST V0
-
8elow l*OV
1L - - - - - -
I
1M - - - - -
I -
lr ‘- l-7
f L.-
r
20 20 2M 2K 21 2G 2E 2c 2A IU 1S 10 10 ltvl tK II Ir; tE 1~ IA
1
22 2x 2v 2T ZR 2P 2N 2L 25 2H 2F 20 2B 1V IT 1R tP 1N IL 1J 1H IF 1~ 1~
1
J=3-46 --
4lways 4
--
AIways 4
--
Atways 1
--
Always 1
-a
Always ’
--
Always i
-e
Always I
2.5v
Always
Always (
-m
Always f
-a
Always 1
Always (
--
Always I
2.5V
Always 1
Always t
Always
--

,,1
CONTROL SYSTEM F3 ‘1
Va: Battew voltage
Incorrect voltage Possible cause
Always OV
l ROOM IOA fuse burned l Open circuit In wiring from ROOM 10A fuse to ECU termina! 1A
Always OV
l Main relay malfunction l Open or short circuit in wiring from main relay to ECU terminal IB
Always OV (starter turns)
l Open or short circuit in wiring from ignition switch to ECU terminal IC
Always OV
Always VB
l Maln relay (FUEL INJ relay) malfunction l Open circuit in wiring from main relay to diagnosis connector terminal +B l Open or short circuit in wiring from diagnosis connector terminal MEN to
ECU terminal 1 D
l Poor connection at ECU connector l ECU malfunction
Always approx. 5V . ECU malfunction
Always below
2.5v
Always Ve -
-
No display on Self- * Main relay (FUEL INJ relay) malfunction
Diagnosis Checker
l Open circuit in wiring from main relay to diagnosis connector terminal + B
“88” displayed and
l Open or short clrcurt in wiring from diagnosis connector terminal FEN to
buzzer sounds con- ECU terminal tF
ti nuousl y
l Poor connection at ECU connector l ECU malfunction
Always QV
l Short circuit in wiring from igniter to ECU terminal 16
Always OV or VB
l Refer to Code No.42 Troubleshooting
(Refer to 323 4-Wheel Drtve Workshop Manual (12?9-IO-89L))
Always VB
Always OV
Always below
2.5V
Atways Ve I ’
l Fuel pump resistor/relay malfunction
l Open or short circurt in wiring from ECU terminal II to fuel pump resis-
tor/relay
A/C does not operate
l A/C reiay malfunction l Open circuit in wiring from ignition switch to A/C relay l Open circuit in wiring from A/C relay to ECU terminal 1J
A/C switch
OFF but l Short circuit in wiring from AIC relay to ECU terminal 1 J
A/C operates . ECU malfunction
l Poor connection at ECU connector l ECU malfunction
Always below 1 .OV a Short circuit in wiring from diagnosis connector terminal TEN to ECU termi-
nal 1K
Always Vs
l Open circuit In wiring from diagnosis connector terminal TEN to ECU terml-
nal IK
-
-
l Open circuit in winrig from diagnosis connector terminal GND to ground’
-
I -
.
. .
-. F3-47