1987 MAZDA 626 display

4B TROUBLESHOOTING WITH SST
INSPECTION PROCEDURE
1. Connect the SST to the check connector, (Green,
6-pin) and the negative battery terminal.
2. Set the select switch to position A.
Note
The check connector is located at the rear of
the left side wheel housing.
86U04A-011
Test connector: Green (1 pin)
3. Ground the test connector (Green, 1-pin) with a
jumper wire.
Note
The test connector is located near the Self-
Diagnosis Checker check connector.
86U04A-012
OO
uu
SELF-DIAGNOSIS CHECKER
(WPUTOft
SELECT
S*

5


o n==ru
o o o o 49 HO 18 9AI
76G04B-005
4. Turn the ignition switch ON.
5. Verify that 88 flashes on the digital display and that
the buzzer sounds for three seconds after turn-
ing the ignition switch ON.
6. If 88 does not flash, check the main relay (Refer
to page 4B—86), power supply circuit, and check
connector wiring.
7. If 88 flashes and the buzzer sounds continuously
for more than 20 seconds, replace the engine con-
trol unit and perform steps 3 and 4 again.
8. Note the code numbers and check for the causes
by referring to the check sequences shown on
pages from 4B—14 to 4B—24. Repair as
necessary.
Note
Cancel the code numbers by performing the
after-repair procedure after repairing.
AFTER-REPAIR PROCEDURE
1. Cancel the memory of malfunctions by disconnect-
ing the negative battery cable and depressing the
brake pedal for at least 2 seconds; then recon-
nect the negative battery cable.
76G04B-134
4B—10

TROUBLESHOOTING WITH SST 4B
2. Connect the SST to the check connector.
3. Ground the test connector (Green, 1-pin) with a
jumper wire.
86U04A-015

Ignition switch:
ON

for six
seconds
4. Turn the ignition switch ON, but do not start the
engine for six seconds.
5. Start and warm up the engine, then run it at
2,500—3,000 rpm for three minutes in neutral.
6. Verify that no code numbers are displayed.
76G04B-006
76G04B-007
Note
The Digital Code Checker (49 G018 9A0) with
the Signal Adapter (49 9200 180) may be used
in place of the Self-Diagnosis Checker (49
H018 9A1).
4B-11

TROUBLESHOOTING WITH SST 4B
CODE NUMBER
Malfunction display
Self-diagnosis Fail-safe Code
No. Output signal pattern subsystem Self-diagnosis Fail-safe

01
ON
OFF

Ignition pulse
No ignition signal
08
Air flow meter
Open
or
short circuit
Maintains basic sig-
nal
at
preset value
09
1 111

Water thermo sensor
Open
or
short circuit
Maintains constant command 35°C (95 °F)
10
Intake
air
thermo sensor (air flow meter) Open
or
short circuit
Maintains constant 20°C (68°F) command
12
£_IUILJIIL

Throttle sensor
Open
or
short circuit
Maintains constant
command
of
throttle
valve fully open
14
OFF
TL
I I nil

Atmospheric pres-
sure sensor Open
or
short circuit
Maintains constant command
of
sea level pressure
15
oTp m 11 [U

Oxygen sensor Sensor output con-tinues less than 0.55V 120 sec. after engine starts (1,500 rpm)
Cancels EG
I
feed-
back operation
17
SLJlMJl

Feedback system Sensor output
not
changed
20
sec.
af-
ter engine exceeds 1,500 rpm
Cancels EGI feed-back operation
25
^JMLJl

Solenoid valve (pres-
sure regulator)
Open
or
short circuit
26
SUUBUIL

Solenoid valve (purge control)
Open
or
short circuit 28
£ mi in nr

Solenoid valve
(EGR) Open
or
short circuit
34
^jmiUTT

Air bypass solenoid
valve (Idle-up
C)

Open
or
short circuit
35
0Nnnnj OFFU u UUU
"fin nnr
Air bypass solenoid
valve (Idle-up
B)

Open
or
short circuit

76G04B-008
Caution
a) If there is more than one failure present, the lowest number malfunction code is dis-
played first, the remaining codes are displayed sequentially.
b) After repairing a failure, turn off the ignition switch and disconnect the negative battery
cable and depress the brake pedal for at least 2 seconds to erase the memory of a mal-
function code.
4B-13

4C TROUBLESHOOTING WITH SST
Check connector: (Green, 6 pin)
49 H018 9A1
86U04A-011
Test connector: (Green, 1 pin)'
INSPECTION PROCEDURE
1. Connect the SST to the check connector. (Green,
6-pin) and the negative battery terminal.
2. Set the select switch to position A.
Note
The check connector is located at the rear of
the left side wheel housing.
3. Ground the test connector (Green, 1-pin) with a
jumper wire.
Note
The test connector is located near the Self-
Diagnosis Checker check connector.
86U04A-012
OO
uu
SELF-DIAGNOSIS CHECKER
MONITOR LAMP SELECT SW «

o o o
o
76G04C-012
4. Turn the ignition switch ON.
5. Verify that 88 flashes on the digital display and that
the buzzer sounds for three seconds after turn-
ing the ignition switch ON.
6. If 88 does not flash, check the control relay (refer
to page 4C—96), power supply circuit, and check
connector wiring.
7. If 88 flashes and the buzzer sounds continuously
for more than 20 seconds check the check con-
nector wiring, then replace the engine control unit
and perform steps 3 and 4 again.
8. Note the code numbers and check for the causes
by referring to the check sequences shown on
pages 4C—16 to 4C—24. Repair as necessary.
Note
Cancel the code numbers by performing the
after-repair procedure after repairing.
AFTER-REPAIR PROCEDURE
1. Cancel the memory of malfunctions by disconnect-
ing the negative battery cable and depress the
brake pedal for at least five seconds.
76G04C-013
4C-12

TROUBLESHOOTING WITH SST 4C
49 H018 9A1
negative battery cable
^ll
Test connector: (Green, 1 pin)
86U04A-015

Ignition switch:
ON

for six
seconds
76G04C-014
2. Connect the SST to the check connector.
3. Ground the test connector (Green, 1-pin) with a
jumper wire.
4. Turn the ignition switch ON for six seconds (do
not start the engine).
5. Start and warm up the engine, then run it at 2,000
rpm for two minutes.
6. Verify that no code numbers are displayed.
PRINCIPLE OF CODE CYCLE
Malfunction codes are determined as shown below
86U04A-017
1. Code cycle break
The time between warning code cycles is 4.0 sec (the time the light is off).
ON
OFF
1 cycle Malfunction code
cycle break
4.0 sec.
86U04A-018
4C—13

4C TROUBLESHOOTING WITH SST
2. Second digit of malfunction code (ones position)
The digit in the ones position of the malfunction code represents the number of times the buzzer
is on 0.4 sec during one cycle.
ON
OFF
1 cycle Malfunction code
1 2 3 cycle break
Malfunction
code: 03
n^j
0.4 0.4 sdc. sec.
4.0 sec.
76G04C-015
3. First digit of malfunction code (tens position)
The digit in the tens position of the malfunction code represents the number of times the buzzer
is on 1.2 sec during one cycle.
It should also be noted that the light goes off for 1.6 sec. between the long and short pulses of
the buzzer.
1 cycle Malfunction code
1 2
~U 0.4
1.2 sec. sec h
1 2|
flfl
First digit
1.6 sec.
cycle break
Malfunction
code: 22
nr
4.0 sec.
Second
digit
76G04C-016
CODE NUMBER
Malfunction display
Sensor or
subsystem Self-diagnosis Fail-safe Malfunction
code no.
Malfunction code output signal pattern
Sensor or
subsystem Self-diagnosis Fail-safe
02 o°nfJLJJL
Ne signal No Ne signal from crank angle sensor during craking
03 oppJUllUl
G signal No G signal Cancels sequencial
injection
05
Knock sensor (only
leaded fuel)
Open or short circuit • Retards ignition timing 4°
76G04C-017
4C—14

TROUBLESHOOTING WITH SST 4C
Malfunction display
Sensor or subsystem Self-diagnosis Fail-safe Malfunction
code no. Malfunction code output signal pattern
Sensor or subsystem Self-diagnosis Fail-safe
08
Air flow sensor Open or short circuit Maintains basic sig-nal at preset value
09 o°pNp II IIL •
Water thermo sensor Open or short circuit Maintains constant 35°C (95°F) command
11 0°FNFJUUL
Intake air thermo sensor (dynamic chamber)
Short circuit Maintains constant 20°C (68°F) command
12
Throttle sensor Open or short circuit Maintains constant command of throttle valve fully open
15 ON n
OFF •L 01
Oxygen sensor Sensor output con-tinues less than 0.55V 120 sec. after engine starts (1,500 rpm or over)
Cancels
EG I
feed-
back operation
17 ON n
OFF L HI il
Feedback system Sensor output not changed 20 sec. af-ter engine starts (1,500 rpm or over)
Cancels
EG I
feed-
back operation
25 0°nfJU1LJIL
Solenoid valve (pres-sure regulator control)
Open or short circuit
26 2LMJIL
Solenoid valve (No.1 purge control)
Open or short circuit
27 ON nn
OFF | _ •111
-ii-Solenoid valve (No.2
purge control)
Open or short circuit
28 ON nn
OFF L Hi nr
Solenoid valve (EGR)
Open or short circuit
34 ^jmiHum
Solenoid valve (Idle speed control)
Open or short circuit
36 °FFJMI«U
Oxygen sensor relay
Open or short circuit
41 <£jimjiuM
Solenoid valve (Vari-able inertia control)
Open or short circuit
76G04C-018
Caution
a) If there is more than one failure present, the lowest number malfunction code is dis-
played first, the remaining codes are displayed sequentially.
b) After repairing a failure, turn off the ignition switch and disconnect the negative battery
cable and depress the brake pedal for at least 5 seconds to erase the memory of a mal-
function code.
4C—15

TROUBLESHOOTING (G4A-EL) 7B
06 4 second period
55 4 second period
63
-*•
4 second period
Repeats above
General Note
1. If there is more than one malfunction, the code
numbers will be displayed on the tester one by one
in a numerical order. In the case of malfunctions,
55, 06, and 63, the code numbers are displayed
in an order of 06, 55, then 63. The display is as
shown.
86U07B-018
When the service connector
is not grounded
Malfunctions YES
NO
Hold indicator YES
flashing NQ
YES
NO
Memory in control unit
2. The hold indicator flashes to indicate the same pat-
tern as the buzzer of the EC-AT Tester when the
EC-AT service connector is grounded.
When the EC-AT service connector is not ground-
ed, the indicator flashes in a constant frequency
while a malfunction is occurring and goes out
if
the
malfunction recovers. However, the warning code
is memorized in the EC-AT control unit.
76G07B-015
Sensors-
Solenoid-valve
Fail-safe program Proces--\Out sing -v puts
The EC-AT control unit has a built-in fail-safe func-
tion for the throttle sensor, the pulse generator, and
the 1-2, 2-3, and 3-4 shift solenoid valves.
If a malfunction occurs, the EC-AT control unit will
control operation of the remaining components ac-
cording to a preset fail-safe program.
The vehicle may still be driven, although the driv-
ing performance will be slightly affected.
79G07C-062
4. The memory of warning codes is canceled by dis-
connecting the negative battery terminal for ap-
prox. five seconds.
79G07C-063
7B-17