Page 144 of 677
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
Page 145 of 677

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
Page 146 of 677

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
Page 147 of 677

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
Page 148 of 677
TRUUBLESHOOT1NG GUIDE
TROUBLESHOOTING GUIDE [BP TURBO]
RELAT1ONSt-W CHART
,
i OUTPUT DEVICE
INPUT DEVfCE
KNOCK SENSOR
1
I
-
I-
3 DIAGNOSIS CONNECTOR
(TEN TERMfNAL)
IGNITION SWITCH
(START POSITION)
0 0 0 Cl
EIL SIGNAL * ’
0 0
0 0
P/S PRESSURE SWITCH
0
1
0 0 A/C SWITCH
0 0 0 0 NEUTRAt AND CLUTCH
SWfTCHES 0 0
0
STOPLIGHT SWITCH
0
0
0 0 0 ATMOSPHERIC PRESSURE
SENSOR (IN ECU) 0
0
THROTTLE SENSOR 0 0 0 0 0
0 INTAKE AfR THERMOSENSOR 0
AlRFLOW METER 0 0
I------ i
0 OXYGEN SENSOR
WATER THERMOSENSOR 0
0 0
O G-SIGNAL
DISTRIBUTOR
I---- Ne-SIGNAL I-L 0 0 L-
0
0
L.- 0 0
L 0 0
93GOF2-i45
*I E/L SIGNAL: Slower fan control switch Second position or higher, cooSing fan operating? headlights ON, or rear wtn-
dow defroster switch ON
Page 150 of 677
![MAZDA 232 1990 Workshop Manual Suplement 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 C MAZDA 232 1990 Workshop Manual Suplement 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 C](/manual-img/28/57056/w960_57056-149.png)
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
Page 153 of 677
![MAZDA 232 1990 Workshop Manual Suplement 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 MAZDA 232 1990 Workshop Manual Suplement 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](/manual-img/28/57056/w960_57056-152.png)
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
Page 154 of 677

TROUBLESHOOTING GUIDE F2
;TEP / t NSPECTION ACTION
4 i Check if throttle valve fully opens when depress- Yes Go to next step
rng accelerator fully
No Check if accelerator cabte is correctly
Installed *
-a If OK, check throttle body*
c=> If not OK, install accelerator cable
correctly*
5 Check if “00” fs dlsptayed on Self-Diagnosis
Yes Go to next step
Checker with ignition switch ON*
NO Malfunction Code No. displayed
SYSTEM SELECT: 1 Check for cause (Refer to specified
check sequence) *
“88” flashes
Check ECU terminal 1 F voltage
Voltage: Approx. f 2V
(Ignition switch ON) CT- page F2-60
i~sT SW: SELF TEST e If OK, replace ECU’
c3 ff not OK, check wiring between
ELECT SW: A ECU and Self-Diagnosis Checker
6 Check if continuity between throttle sensor termi- Yes Go to next step
nals IDt and E ts as shown’
7
Connect System Selector to diagnosis connector Yes Check if ignition timing advances when
and set Test Switch to “SELF TEST” and check accelerating
for correct ignition timing at idle after warm-up’
e If advances, go to next step
Ignitian timing: BTDC 10 f 1 D
=S If no advance, check ECU terminal
voltages
No Adjust
8
Check of ECU terminal voltages are OK Yes Go to next step
CT page F2-60
No Check for cause
9
Check for correct intake manrfold vacuum at idle Yes Go to next step
intake manifoId vacuum:
! More than 450 mmHg (17.7 inHg)
NO Check ior air leakage 07 intake air sys-
tem components
* Refer to 323 Workshop Manual [1203-IO-89F (Europe) or 1204-IO-89F (Australia)].
F2-37