1990 MAZDA 232 fuel

F2 SELF-DIAGNOSlS FUNCTION
Troubleshooting
If a malfunction code number is shown on the SST (49 l-l01 8 9Ai, 49 B019 9AO), check for the cause
using the chart related to the code number shown, [Regarding code numbers except 05, 24, and 42, refer
to “Troubleshooting” in Workshop Manual [I 203-I O-89F (Europe) or 1204-f 0-89F (Australia)].
r C :ODE No. 05 (KNOCK CONTROL UNIT)-BP TUR80
;TEP
2
3 I INSPECTION
Check knock sensor and knock control unit
circuit for poor connectlon ACTtON
Yes Repalr or replace connector
Check knock control unit terminal voltage with
ignition switch ON
Check that voltage at ECU terminal 2J is
approx. 4V at idle
rs7 page F2-64 Yes Recheck ECU connector for poor
connection
4 If OK, replace ECU
4 If not OK, repair or replace connector
NO Repair wiring harness (R/Y) between
ECU terminal 2J and knock control unit
93GOF2-7:
Circuit Diagram
I
ECU
IGNITION
SWITCH
15A BATTERY
MAIN
RELAY
(FUEL 1N.J)
l W/L Y/i3 G/O W RIB R/L
YIL
jr- -- - - 1 BlLG
-
-
MCK CONTROL
I
. :
MAIN RELAY (FUEL INJ)
W/G BIW
C&=&A
KNOCK CONTROL UNIT
W/R EMLG RN Y/L
1
KNOCK SENSOR

SELF-DIAGNOSIS FUNCTION F2
:UDE No. 24 (FUEL PUMP RESISTOR/RELAY)-BP TURBO
STEP INSPECTION ACTtON
1 1 Disconnect connector from ECU and check if
1 battery voltage exists at connector terminal 1 I (L) Yes Check ECU terminal connector for poor
connection
with ignition switch ON
e If OK. replace ECU
c=> If not OK, repair or replace connector
NO Go to next step
2 In same condltlon as Step 1, check if battery
Yes Repair wiring harness (W/R)
voltage exists at resistor/relay connector terminai- I
wire (W/R)
NO Go to next step
3 Check if there is continuity between fuel pump
Yes Check for short or open circuit
in wiring
res!stor/relay terminals C (‘W/R) and D (L) from main relay (FUEL INJ relay) to
t resistor/relay
NO Replace resistor/relay
93GOF2-74 1 Circuit Diagram
IGNITION
SWITCH DIAGNOSIS
CONNECTOR
rl
F/P TERMINAL *
BATTERY
IGNlTlON
0fP
W/R
FUEL
PUMF
B
c W/R 7
FUEL PUMP
- RESISTOR/RELAY
\I
I/
ECU MAIN RELAY
Of1
W/G . LGrf Grw l v L/O R/Y LGlR YfL B/LG
RIB 1
I GIB J 1 1 [ WR LG ] Y , UW~LGIw/ * 1 W ] 810 WIG BfW
I
I I I
1 I I
I
&J,~&&&l&&c!zr5& &l~&cLa~~c!zch&&&&~
1~ IS 10 10 IM 1K II tC 1E 1C IA 2Y 2w 2u 2s 20 20 28.4 2K 21 2G 2E 2C 2A
IV 17 ?R IP 1N 1~ IJ III IF ro :8
rrrrrT?rrTT
BRff t BIG 1 R/W ! t/B 1 WIB 1 W/R
BIL UY O/B WN
CIRCUIT OPENING RELAY
FUEL PUMP FUEL PUMP RESlSTOR/RE~Y
v WIRBIP
B - LG
93GOF2.74
F2-29

F2 SELF-DIAGNOSlS FUNCTION
XIDE No. 1 42 (SOLENOID VALVE - WASTEGATE)-BP TURBO STEP
tNSPECTiON
ACTION
1
Disconnect connector from ECU and check if Yes Check ECU terminal connector for poor
battery voltage exists at connector terminal f H connection
(O/B) with Ignition switch ON
e If OK, replace ECU
4 tf not OK, repalr or replace connector
No Go to next step
2 in same condition as Step 1, check if battery Yes Repair wiring harness voltage extsts at solenoid valve connector
terminal-wire
NO Go to next step
3 Check if solenoid valve is OK
Yes Check for short or open circuit in wiring
.r3 page F2-46 from main relay (FUEL INJ relay) to
solenoid valve
NO Replace solenoid valve
Circuit Diagram
BA-iTERY
15A k
IGNITION SWITCH v /\: ./
WIG
B/w O/B
‘L a,
d
MAIN RELAY
(FUEL INJ)
WASTEGATE
SOtENOlD VALVE
ECU
WASTEGATE MAIN RELAY (FUEL INJ)
SOLENOfD VALVE
RIB 011 GIB WIG * LGIY L GM,
l v L/R
I
A WIG %fw
W/R
1u
10 1M 1K 71 B O/B
I I
i
B&Y B/L B;G UY Rh’ * I
I
IJB d/B WiB Wff W/R W/R B
F2-30

F2 TROUBLESt=iUUTlNG GUIDE
SYMPTOM TROUBLESHOOTING
Regarding symptom troubleshooting except LACK OF POWER, POOR XCELERATION, KNOCKING, and
HIGH UIL CONSUMPTION, refer to Workshop Manual [I 203-l O-89F (Europe) or 1204-l O-89F (Australia)].
19 LACK OF POWER [BP TIJR801
DESCRIP- *Performance poor under load when throttle valve wide open
TION *Reduced maximum speed
l Idle condition normal
[TROUBLESHOOTING HINTS1
3 Wastegate always open or opens early
3 Turbocharger damage
@ Factors other than engine malfunction
*Clutch sllpping
l Brake dragging
*Low tire pressure
l Incorrect tire size l Overloaded vehicle
@ Low intake air amount
*Throttle valve not open fully
*Clogged intake air system
TEP INSPECTlON
1
Install pressure gauge in intake air pipe and
check boost pressure at engine speed of
4,000
wm
CT page F2-45
Boost pressure:
More than 2.0 kPa (0.02 kglcm2, 0.3
psi)
@ Air/Fuel mixture lean
l Fuel iine pressure decreases l Fuel injection malfunction
@ Poor ignrtjon
@ Low engine compression
@ Alcohol blended fuel used
@ Knock control system malfunction
ACTION
Yes Go to Step 3
NO Check for air leakage and exhaust gas
leakage
4 If OK, go to next step
4 In not OK, repair
2 Check wastegate
Yes Remove intake air pipe from turbo-
f7 page F2-45 charger and check if compressor wheel
rotates smoothly t7 page F2-46
4 If OK, check air cleaner element
and throttle valve
+ If not OK, replace turbocharger
3 Check factors other than engrne Yes
l Clutch slipping Go to next step
1 8rake dragging
’
l Low tire pressure NO Repair or adjust
l Incorrect tire srze
FZ-32

TROUBLESHOOTING GUIDE F2
]sTFP 1 INSPECTION ACTION
I
Aerator depressed ful ty
rminal 1F voltage
: SELF TEST
ignition timing: BTDC 10 = I*
8 Check for correct fuel line pressure at idle’ Yes Check if fuel line pressure decreases
when accelerating quickly
Fuel line
pressure: 265-314 kPa (2.7-3.2 kg/cm’, 38-46 psi)
(vacuum hose to pressure regulator dis-
connected) 4 If decreases check fuel pump
maximum pressure*
If OK, check fuel line and filter for
clogging
4 If no decrease, go to next step
NO Low pressure
Check fuel irne pressure while pinching
fuel return hose
4 If fuel line pressure quickly in-
creases, check pressure
regulator' e If fuel lrne pressure gradually in-
creases, check for cloggrng be-
tween fuel pump and pressure
regulator
If not clogged, check fuel pump
maximum pressure* High pressure
Check of fuel return line is ctogged
4 If OK, replace pressure regulator
e If not OK. replace
- _
* Refer to 323 Workshop Manual
[I 203-1 O-89F (Europe), or 1204-lU-89F (Australra)].
FZ-33

TROUBLESHUOT1NG GUIDE F2
;TEP
14
15
16 Change fuel and check if condjtjon improves INSPECTION
Check if resistance of rgnrtm
coil IS OK’
Resistance (at 20°C [SS*Fj):
Primary coil winding _....-.. Cl.81 -0.99Q
Secondary coil winding.,.. IO-16 kQ ACTION
Yes Go to next step
PRIMARY COIL
WINDING SECONDARY COIL
WIND tNG
Check fur correct engine compressron”
Yes Go to next step
Engine compression:
785 kPa (8.0 kg/cm2, 1 I4 psi)-300’ rpm L 1
No Check engine condition *
l Worn p&ton, piston rings or cylinder
wall
l Defective cylinder head gasket l Distorted cylinder head l Improper valve seating
l Valve sticking in guide
Yes Change fuel to another brand
No
I I Try known good ECU and check if con-
dition imDroves
* Refer to 323 Workshop Manual [ 1203-lo-89F (Europe) or 1204-l O-89F (Australia)l.
93GOF2-74 6
F2-35

F2 TROUBLESHOOTING GUIDE
20 POOR ACCELERATION [BP TURBO]
IESCRIP- . Performance poor while accelerating
rm
l Idle condition normal
[TROUBLESHOOTING HINTS]
3 Wastegate always open or opens early @ Low intake air amount
3 Turbocharger damage
l Throttle valve not open fully
3 Factors other than engine malfunction *Clogged intake air system l
Ciutch slIpping @ Air/Fuel mixture Iean l Brake draggrng l fuel line pressure decreases
l low tire pressure l Fuel Injection malfunction
l Incorrect tire size @ Poor Ignition
. Overloaded vehicle @ Low engine compression
@ Atcohol blended fuel used
TEP INSPECTION ACTION
-l Install pressure gauge
in intake air pipe and I Yes
1 Go to Step 3
check boost pressure at engine speed of 4,000
rpm
w page F2-45
Boost pressure:
More than 2.0 kPa (0.02 kglcm2, 0.3 psi)
No Check for air leakage and exhaust gas
leakage
4 If OK, go to next step
4 If not OK, repair
2 Check wastegate w page F2-45
Yes Remove Intake air pipe from turbo-
charger and check if compressor wheel
rotates smoothly w page F2-46
c3 If OK, check air cleaner element
and throttle valve
4 If not ok, replace turbocharger
3 Check factors
other than engine
Yes Go to next step l Clutch stipprng l 5rake dragging l Low tire pressure
No l Incorrect ttre size Repair or adjust
FZ-36

F2 TROUBLESHUOTtNG GUIDE
check fuel pump maxi-
fuel line and filter for
pump and pressure
High pressure
Check if fuel line is clogged
II. Measure resistance
r--- ---_--es-,
DAMAGE AND
DETERIORATION
* Refer to 323 Workshop Manual f1203-1 O-89F (Europe) 12041U-89F (Australia)].
F2-38