check engine light MAZDA 626 1987 Owner's Manual

CONTROL SYSTEM 4C
Terminal Voltage
If the input and output devices wiring are normal, but the engine control unit terminal voltage is incor-
rect, replace the engine control unit.
Terminal Input Output Connection to Voltage (After warming-up) Remark Terminal Input Output Connection to Ign: ON Idle Remark
1A — — — — — —
1B o Self-Diagnosis Checker (Code No.)
For 3sec. after ignition switch OFF ->• ON: below 2.5V (Buzzer sounds) After 3sec.: approx. 12V (Buzzer does not sound)
• Using Self-Diagnosis Check-er and test con-nector grounded • Buzzer sounds: below 2.5V • Buzzer does not sound: approx. 12V
1C o
Solenoid valve (Variable inertia control) Approx. 12V
Above 5200 rpm (Unleaded fuel) or 5400 rpm (Leaded fuel): Below 2.5V
1D o Self-Diagnosis Checker (Monitor lamp)
For 3sec.after igni-tion switch OFF -» ON:
approx. 5V (light il-luminates)
After 3sec.: approx. 12V (light does not illuminate)
(Test connector grounded) approx. 5V (Test connector not grounded) Monitor lamp ON: approx. 5V Monitor lamp OFF: approx. 12V
With Self-Diagnosis
Checker
1E O Idle switch Accelerator pedal released: OV
Accelerator pedal depressed: approx. 12V
1F o A/C relay A/C switch ON: below 2.5V
A/C switch OFF: approx. 12V Blower motor ON
1G O Neutral or clutch switch
In-gear condition Clutch pedal depressed: approx. 12V Clutch pedal released: OV
MTX (Neutral: con-stant approx. 12V)
1H
(U/F) o Water thermo
switch
Approx. 12V Radiator temp.: be-low 17°C (63°R 1H
(U/F) o Water thermo
switch OV Radiator temp.:
above 17°C (63°F)
11 o Electrical load control unit E/L switch ON: below 2.5V
E/L switch OFF: approx. 10—12V
Electrical load: Rear defroster switch
Headlight switch Blower motor switch (3rd & 4th position) Electrical fan switch
1J — — — — —
1K o P/S pressure
switch
Constant approx.
12V
P/S ON: below 2.5V P/S OFF: approx. 12V
1L o A/C switch A/C switch ON: below 2.5V A/C switch OFF: aDDrox. 12V Blower motor: ON
1M o Distributor
(Ne signal) OV or 5V Approx. 2.0V
1N o Distributor (G signal) OV or 5V Approx. 1.2V
Note
Terminals labeled "U/F" are only for unleaded fuel.
4C-99

4C CONTROL SYSTEM
E/L CONTROL UNIT
Inspection
1. Connect a voltmeter between the E/L control unit
and a ground.
2. Start the engine and check the terminal voltages
as described below.
76G04C-180
Terminal Input Output Connection to Voltage (after warm-up) Remarks Terminal Input Output Connection to Ignition switch: ON Idle Remarks
A
(BW) — — Ignition switch Approx. 12V
B — — — — — —
C
(B) — — Ground OV
D (LY) O Electrical fan relay Approx. 12V Coolant temp.: below 97°C (207°F) D (LY) O Electrical fan relay
Below 1,5V Coolant temp.:
above 97°C (207°F)
E (GY) Control unit (11) OV E/L: ON E (GY) Control unit (11)
Approx. 12V E/L: OFF
F (W) O Headlight switch Approx. 12V Headlight switch:
ON F (W) O Headlight switch
Below 1,5V Headlight switch:
OFF
G (LB) o Blower motor switch Below 1.5V Blower motor switch: ON (3rd or 4th position) G (LB) o Blower motor switch
Approx. 5V Others
H
(BL) o Rear defroster
switch
Below 1.5 V Rear defroster
switch: ON H
(BL) o Rear defroster
switch Approx. 12V Rear defroster switch: OFF
76G04C-181
Replacement
1. Replace the E/L control unit.
2. Install in the reverse order of removal.
76G04C-182
4C—102

DISTRIBUTOR 5
7BU05X-075
86U05X-048
76G05X-007
DISTRIBUTOR
SPARK TEST
1. Disconnect the distributor lead from the distributor.
2. Hold it with insulated pliers approx. 5—10 mm
(0.20—0.39 in) from a ground.
3. Crank the engine and check that a strong blue
spark is visible.
4. If there is no spark, the ignition coil or pick-up coil
may be bad.
Check once again after replacing the ignition coil
or pick-up coil.
IGNITION TIMING
1. Warm up the engine to the normal operating tem-
perature.
2. Turn all electric loads OFF.
3. Connect a tachometer and timing light to the
engine.
4. Connect a jumper wire between the test connec-
tor and ground. (Only for FE DOHC)
5. Check the idle speed. Set to the specified speed
if necessary.
Idle speed: 750 ± 50 rpm (FE DOHC)
800 t58 rpm (F6, F8 FE—MTX)
900 i58 rpm (F8, FE—ATX
in "P" range)
950 -5o rmp (F6—ATX
in "P" range)
6. Check that the timing mark (Yellow) on the crank-
shaft pulley and the mark on the timing belt cover
are aligned.
Ignition timing:
FE DOHC: 12 ± 1° BTDC
(Test connector grounded)
Others: 6 ± 1°
(Vacuum hoses disconnected and
plugged)
76G05X-008
5—11

DISTRIBUTOR
8.
If
the mark is not aligned, loosen the distributor lock
bolt, and turn the distributor housing to make the
adjustment.
9. Reconnect the vacuum hoses, or disconnect the
jumper wire from the test connector.
10. Tighten the distributor lock bolt to specified torque.
Tightening torque:
18.6—25.5 Nm
(1.9—2.6 m-kg, 13.7—18.8 ft-lb)
86U05X-051
SPARK CONTROL (Except FE DOHC)
Centrifugal Advance
1. Warm up the engine to the normal operating tem-
perature.
2. Check that the idle speed and initial ignition tim-
ing are correct.
3. Disconnect the vacuum hoses from the vacuum
control unit and plug them.
76G05X-009
F6
Engine Speed (rpm)
4. While gradually increasing the engine speed, use
a timing light to check the advance on the pulley.
Excess advance weak governor spring
(If the governor spring is broken,
the advance will rise very high)
Insufficient advance...governor weight or cam
malfunction
86U05X-053
F8
Engine Speed (rpm) Engine Speed (rpm)
5-12

DISTRIBUTOR 5
FE West Germany (MTX)
24c
14<
0 0) O)
a>
®
O) c a> ^
I 0 1.76° 3.36° 5.32°
Engine Speed (rpm)
FE 12 valve (Carb.)
© ©
118°
12° O) c (0
c CO
6 o 1,200 2,400 4,0005,000
Engine Speed (rpm)
FE West Germany (ATX)

oT
24' 0) a> © "D
© O) c CO JX c CO
14c
6 0 1,300 3,350 5,320
Engine Speed (rpm)
EF EGI a) ©
O) a> ©
o> c ©
C CO
O
18°
12°
1,000 2,600 4,600 5,800
Engine Speed (rpm)
F6, F8 © ©
O) © tj, ©
cn
« 8°
c a)
6 o
86U05X-054
100 (3.94) 300 (11.81)
mmHg (inHg)
Vacuum Advance
1. Warm up the engine to the normal operating tem-
perature.
2. Check that the idle speed and ignition timing are
correct.
3. Disconnect the vacuum hoses from the vacuum
control unit, and plug them.
4. Connect a vacuum pump to the vacuum control
unit.
5. Apply vacuum and check the advance with the tim-
ing light.
86U05X-055
5—13

ALTERNATOR 5
TROUBLESHOOTING
Preliminary Check
1. Turn the ignition switch ON, and check that
the alternator warning light illuminates.
2. Start the engine, and check that the alternator warning light goes off.
76G05X-024
1. Alternator warning light always not illuminate
76G05X-025
2. Alternator warning light illuminates when engine running
76G05X-026
5-23

ALTERNATOR 5
Warning
Disconnect the nagative battery terminal when disconnect or reconnect B terminal.
TEST 1
1. Disconnect the alternator connector (2-pin).
2. Connect the SST.
4. Connect the red clip of the adapter harness to the battery
(
+
),
and check that the red
lamp and green lamp illuminate.
5. Start the engine and check that both lamps go off.
86U05X-010
TEST 2
1. Connect an ammeter (75A min.) between the wire and the B terminal.
2. Turn all headlights and accessories on, and depress the brake pedal.
3. Start the engine and check that output current is 70A (RF-CX: 75A) or more at
2,500—3,000 rpm of the engine speed.
Caution
Do not ground the B terminal.
76G05X-029
B terminal
5-25

7B ELECTRICAL SYSTEM COMPONENTS
Terminal Connected to Voltage Condition
1J — — —
1K — — —
1L (Input) Idle switch Below 1.5V At idle 1L (Input) Idle switch Approx. 12V Other speeds
1M — — —
1N (Input) Brake light switch Approx. 12V Brake pedal depressed 1N (Input) Brake light switch Below 1.5V Brake pedal released
10 (Input) Throttle sensor
Approx. 5V Ignition switch ON 10 (Input) Throttle sensor Below 1,5V Ignition switch OFF
1P (Input)
Throttle sensor
Approx. 0.5—4.3V Throttle valve fully closed to fully open
1Q (Input) Vehicle speed sensor
Approx. 4.5V During driving
1Q (Input) Vehicle speed sensor Approx. 4.5V or below 1.5V Vehicle stopped
1R (Ground) Throttle sensor Below 1,5V —
1S (Input) Pulse generator Approx. 12V Engine running 1S (Input) Pulse generator Below 1,5V Engine stopped
1S (Ground) Pluse generator Below 1.5V —
2A (Battery power) Battery Approx. 12V Ignition switch ON 2A (Battery power) Battery Below 1,5V Ignition switch OFF
2B (Ground) Body ground Below 1,5V —
2C (Memory power) Battery Approx. 12V —
2D (Ground) Body ground Below 1,5V —
2E (Output) 1-2 shift solenoid valve Approx. 12V
Refer to page 7B—26 of solenoid valve
operation table
2E (Output) 1-2 shift solenoid valve Below 1.5V Refer to page 7B—26 of solenoid valve
operation table
2F (Output) 2-3 shift solenoid valve Approx. 12V
Refer to page 7B—26 of solenoid valve
operation table
2F (Output) 2-3 shift solenoid valve Below 1,5V
Refer to page 7B—26 of solenoid valve
operation table
2G — — —
2H (Output) 3-4 shift solenoid valve Approx. 12V Refer to page 7B—26 of solenoid valve operation table 2H (Output) 3-4 shift solenoid valve Below 1.5V
Refer to page 7B—26 of solenoid valve operation table
21 — — —
2J (Output) Lock-up solenoid valve Approx. 12V Lock-up 2J (Output) Lock-up solenoid valve Below 1,5V Other
2K (Output) Hold indicator Below 1,5V Hold mode 2K (Output) Hold indicator Approx. 12V Other modes
2L (Output) Mode indicator Approx. 12V Hold mode 2L (Output) Mode indicator Below 1,5V Power or economy mode
2M (Output) EC-AT Tester
(malfunction code)
Approx. 12V Normal
2M (Output) EC-AT Tester
(malfunction code) Below 1,5V If malfunction present 2M (Output) EC-AT Tester
(malfunction code) Code signal Self-diagnosis check connector grounded
2N — — —
20 (Input) Fluid temperature switch Below 1,5V Above 150°C (302°F) 20 (Input) Fluid temperature switch Approx. 10—12V Below 143°C (289°F)
2P (Input) EC-AT check connect Approx. 12V —
76G07B-084
7B-70

INSPECTION AND REPAIR 7B
Inspection
Check the following and replace any faulty parts.
1. Damaged or worn valves
2. Damaged oil passage
3. Cracked or damaged valve body
4. Operation of each valve
5. Weakened spring
Spring

Spring name Outer dia.
mm
(in) Free length
mm (in)
Wire dia.
mm
(in) Spring color
1-2 accumulator small spring F8 engine 9.9 (0.400) 84.7 (3.335) 1.2 (0.047) Red
1-2 accumulator large spring
FE engine 13.0 (0.512) 73.2 (2.881) 1.8 (0.071) Pink 1-2 accumulator large spring F8 engine 16.0 (0.630) 84.7 (3.335) 2.0 (0.079) White
Bypass spring 5.0 (0.197) 25.1 (0.988) 0.7 (0.028) Yellow
Servo control spring 4.9 (0.193) 27.1 (1.067) 0.5 (0.020) Light blue
2-3 timing spring 8.3 (0.327) 26.5 (1.043) 0.8 (0.031)
—

N-R accumulator rear spring 11.1 (0.437) 68.2 (2.685) 1.0 (0.039) Blue
N-D accumulator front spring 9.8 (0.386) 60.9 (2.398) 1.1 (0.043) Yellow
Low reducing spring 8.7 (0.343) 38.3 (1.508) 0.9 (0.035) Black
OD release spring 6.0 (0.236) 32.6 (1.283) 0.6 (0.024) Orange
Coasting bypass spring 5.8 (0.228) 31.3 (1.232) 0.6 (0.024) Yellow
3-2 timing spring 8.2 (0.323) 28.55 (1.124) 0.8 (0.031) Maroon
3-2 capacity spring 5.55 (0.219) 30.5 (1.201) 0.55 (0.022) Light green
Throttle relief ball spring 6.6 (0.260) 20.3 (0.799) 0.8 (0.031) Light green

76G07B-165
Assembly
1. Install the 3-2 capacity valve, 3-2 capacity spring,
stopper plug, and stopper pin.
2. Install the 3-2 timing valve, 3-2 timing spring, and
retainer.
83U07B-287
3. Install the coasting bypass plug, coasting bypass
valve, and coasting bypass spring.
4. Apply ATF to the O-rings, and install them onto the
piston; then insert the N-R accumulator rear spring,
and N-R accumulator piston.
5. Apply ATF to the O-rings, and install them onto the
piston; then insert the N-D accumulator piston, and
N-D accumulator front spring.
83U07B-288
7B—161

ELECTRIC COMPONENTS 7C
76G07C-036
76G07C-037
76G07C-038
ELECTRIC COMPONENTS
INHIBITOR SWITCH
Inspection
1. Check that engine starts only at P and N range.
2. Check that the backup lights illuminate in R range
with the ignition switch ON.
3. If the inhibitor switch is not operating properly, dis-
connect it and check the continuity between the
terminals.
Connection guide
Position
N
D, 1, 2
Connector terminal
-O
O -O
-O
O—O: Indicates continuity
4. If not correct, replace the inhibitor switch.
KICK-DOWN SWITCH
Inspection of Terminal Voltage
1. Turn the ignition switch ON.
2. Check the voltage at terminal (V) with a voltmeter.
Depressing stroke Terminal voltage
7/8-8/8 (Full) Approx. 12 V
0-7/8 Below 1,5V
3. If not correct, check the wiring harness or switch,
or adjust the switch position.
Inspection of Switch
1. Disconnect the kick-down switch connector.
2. Check for continuity of the switch with an
ohmmeter.
Switch Continuity
Pushed Yes
Released No
3. If not correct, replace the kick-down switch.
83U07B-060
7C—23