1987 MAZDA 626 brake light

SWITCH MONITOR FUNCTION 4B
Idle switch
76G04B-026
Brake light switch
76G04B-027
Blower switch
76G04B-028
A/C switch
76G04B-029
4B—27

DECELERATION CONTROL SYSTEM 4B
COMPONENT DESCRIPTIONS
Component Function Remarks
Brake light switch Detects braking operation (deceleration);
sends signal to engine control unit
Clutch switch Detects in-gear condition;
sends signal to engine control unit Switch ON when clutch pedal released
Dashpot (MTX) Prevents sudden closing of throttle valve during deceleration or shifting Adjustment speed: 1,900—2,100 rpm
Engine control unit Detects signals from input sensors and switches; cuts fuel injection
Idle switch Detects when throttle valve fully closed; sends signal to engine control unit Installed in throttle sensor
Ignition coil (-) terminal Detects engine speed; sends signal to engine control unit
Neutral switch Detects in-gear condition; sends signal to engine control unit Switch ON when in-gear
Water thermo sensor Detects coolant temperature; sends signal to engine control unit
Water thermo switch Detects radiator coolant temperature; sends signal to engine control unit ON: above 17°C (63°F)
76G04B-089
4B—65

CONTROL SYSTEM 4B
CONTROL SYSTEM
Atmospheric
pressue sensor
Engine control unit
Brake light switch
Clutch switch
Circuti opening
relay
E/L control unit
Air flow meter
Neutral switch
76G04B-129
The control system consists of the input devices and the engine control unit. The engine control unit
controls the fuel injection amount (EGI), fuel injection pressure, bypass air amount, switch monitor func-
tion, and fail-safe function.
4B—83

4B CONTROL SYSTEM
RELATIONSHIP CHART
Input Devices and Output Devices
BRAKE LIGHT SWITCH O X X X X X X X X X
ELECTRICAL LOAD CONTROL UNIT X X X X X X X X O X
P/S PRESSURE SWITCH* X X X X X X X X O X
A/C SWITCH O X X X X O O X X O
IGNITION SWITCH
(STA

POSITION) O O X O X X X X O O
INHIBITOR SWITCH o X X X O X X X X O
NEUTRAL
AND
CLUTCH SWITCH o X X X X X X X X O
OXYGEN SENSOR o X X X X X X X X X
WATER THERMO SWITCH (RADIATOR) o X X X O X X X X X
ATMOSPHERIC PRESSURE SENSOR o X X X X O X O O X
INTAKE
AIR
THERMO SENSOR o X X O X X X O O X
WATER THERMO SENSOR o X X O O O X X o X
IDLE SWITCH o o X O X X X X o X
THROTTLE SENSOR o O X X O X X X X O
AIR FLOW METER o X X X X O X X X X
IGNITION COIL o O X O O O X X o O

INPUT
DEVICES
OUTPUT
DEVICES
FUEL
INJECTION
AMOUNT FUEL
INJECTION

TIMING
PRESSURE
REGULATOR
EGR
PURGE
IDLE-UP
(A)*
IDLE-UP
(B)

IDLE-UP

(C)

rr

INPUT
DEVICES
OUTPUT
DEVICES
INJECTOR
AIR

VALVE
SOLENOID
VALVE
AIR

BYPASS
SOLENOID
VALVE
AIR

CONDITIONEI

76G04B-108
4B-84

4B CONTROL SYSTEM
Terminal Voltage
If the input and output devices and related wiring are normal, but the engine control unit terminal volt-
age is incorrect, replace the engine control unit.
Terminal Input Output Connection to Voltage (After warming-up) Remarks Terminal Input Output Connection to IGN: ON Idle Remarks
1A — — — — —
1B o Self-Diagnosis Checker (Code number)
For 3sec. after ignition switch OFF ->• ON: below 6.2V (Buzzer sounds) After 3sec.: Battery voltage (Buzzer does not sound)
• Using Self-Diagnosis Check-er and test con-nector grounded • Buzzer sounds: below 6.2V • Buzzer does not sound: Battery voltage
1C — — — — —
1D o Self-Diagnosis Checker (Monitor lamp)
Test connector grounded
For 3sec. after igni-tion switch OFF ON:
below 6.2V (light il-luminates) After 3sec.: Battery voltage (light does not illuminate)
(Test connector grounded) approx. 10V (Test connector not grounded) Monitor lamp ON: below 6.2V Monitor lamp OFF: Battery voltage
With Self-Diagnosis
Checker
1E O Idle switch Accelerator pedal released: below 1.5V
Accelerator pedal depressed: Battery voltage
1F o A/C relay A/C switch ON: below 2.5V A/C switch OFF: Battery voltage
Blower motor ON
1G — — — — —
1H o Water thermo switch Below 1,5V Radiator temp.:
above 17°C (63°F)
11 o Electrical load con-trol unit Electrical load ON: below 1.5V Electrical load OFF: Battery voltage Electrical load: Rear defroster Headlight Blower motor (3rd & 4th position) Electrical fan
1J o Brake light switch Brake pedal released: below 1.5V
Brake pedal depressed: battery voltage
1K — — — — — —
1L o A/C switch A/C switch ON: below 1.5V
A/C switch OFF: battery voltage
Blower motor: ON
1M o Ignition coil © terminal Battery voltage *1 Battery voltage *1 Engine Signal Monitor: green and red lights flash
1N — — — — —
10 — — — —
4B-88

CONTROL SYSTEM 4B
Replacement
1. Disconnect the negative battery cable.
2. Remove the front console covers (right and left).
3. Disconnect the connectors from the control unit.
4. Replace the control unit.
NEUTRAL SWITCH
Inspection
1. Disconnect the neutral switch connector.
2. Connect an ohmmeter to the switch.
3. Check continuity of the switch.
Transmission Continuity
In neutral No
In other ranges Yes
4. After checking, connect the switch connector.
Note
Refer to section 7A for replacement of the
neutral switch.
CLUTCH SWITCH
Inspection
1. Disconnect the clutch switch connector.
2. Connect an ohmmeter to the switch.
3. Check continuity of the switch.
Pedal Continuity
Depressed No
Released Yes
4. After checking, connect the switch connector.
Note
Refer to section 6 for replacement of the
clutch switch.
BRAKE LIGHT SWITCH
Inspection
1. Disconnect the brake light switch connector.
2. Connect an ohmmeter to the switch.
3. Check the continuity of the switch.
Pedal Continuity
Depressed Yes
Released No
4. After checking, connect the switch connector.
Note
Refer to section 11 for replacement of the
brake switch.
4B-91

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
AUTOMATIC TRANSAXLE
(Electronically Controlled and 4-Speed)
OUTLINE 7B— 2
SPECIFICATIONS 7B— 2
COMPONENT LOCATION 7B— 3
STRUCTURAL VIEW 7B— 5
OPERATION OF COMPONENTS 7B— 6
FLUID PASSAGE LOCATION 7B— 9
TROUBLESHOOTING (G4A-EL) 7B— 12
GENERAL NOTE 7B— 12
STEP 1
(WARNING CODE RETRIEVAL) 7B— 15
STEP 2
(PRELIMINARY INSPECTION) 7B— 22
STEP 3 (SIGNAL INSPECTION) 7B— 24
STEP 4 (STALL TEST) 7B— 27
STEP 5 (TIME LAG TEST) 7B— 30
STEP 6 (OIL PRESSURE TEST) 7B— 31
STEP 7 (ROAD TEST) 7B— 34
TROUBLESHOOTING (G4A-HL) 7B— 41
GENERAL NOTE 7B— 41
STEP 1
(PRELIMINARY INSPECTION) 7B— 44
STEP 2 (ELECTRICAL
SYSTEM INSPECTION) 7B— 47
STEP 3 (STALL TEST) 7B— 49
STEP 4 (TIME LAG TEST) 7B- 52
STEP 5 (ROAD TEST) 7B— 53
STEP 6 (OIL PRESSURE TEST) 7B— 58
ELECTRICAL SYSTEM
COMPONENTS 7B— 63
MODE SWITCH (G4A-EL) 7B— 63
HOLD SWITCH (G4A-EL) 7B— 63
OD OFF SWITCH (G4A-HL) 7B— 64
INHIBITOR SWITCH 7B- 65
WATER TEMPERATURE SWITCH 7B— 66
FLUID TEMPERATURE SWITCH
(G4A-EL) 7B— 66
BRAKE LIGHT SWITCH
(G4A-EL) 7B— 66
KICK-DOWN SWITCH (G4A-HL) 7B— 67
PULSE GENERATOR (G4A-EL) 7B- 68
VEHICLE SPEED SENSOR
(G4A-EL) 7B— 68
CRUISE CONTROL SWITCH
(CRUISE CONTROL UNIT) 7B— 68
IDLE SWITCH AND THROTTLE
SENSOR (G4A-EL) 7B— 68
OD RELEASE SOLENOID
VALVE (G4A-HL) 7B— 68
SOLENOID VALVES (G4A-EL) 7B— 69
NO LOAD SIGNAL (G4A-EL) 7B— 69
MODE, AND HOLD INDICATOR
LIGHT (G4A-EL) 7B— 69
OD OFF INDICATOR LIGHT
(G4A-HL) 7B— 69
EC-AT CONTROL UNIT
(G4A-EL) 7B— 69
ON-VEHICLE MAINTENANCE 7B— 71
AUTOMATIC TRANSAXLE
FLUID (ATF) 7B— 71
SELECTOR LEVER 7B— 72
THROTTLE CABLE 7B— 73
CONTROL VALVE BODY 7B— 77
OIL STRAINER 7B— 79
ADJUSTMENT OF 2-4 BRAKE
BAND 78— 80
REPLACEMENT OF
DRIVESHAFT OIL SEAL 7B— 80
OIL COOLER 7B— 81
GOVERNOR (G4A-HL) 7B— 82
REMOVAL 7B— 83
PRECAUTION 7B— 83
DISASSEMBLY 7B— 88
DISASSEMBLY-STEP 1 7B— 88
DISASSEMBLY-STEP 2 7B— 94
DISASSEMBLY-STEP 3 7B— 99
DISASSEMBLY-STEP 4 7B—103
INSPECTION AND REPAIR 7B—107
PRECAUTION 7B—107
TORQUE CONVERTER 7B—107
OIL PUMP 7B—108
CLUTCH ASSEMBLY 7B—113
SMALL SUN GEAR AND
ONE-WAY CLUTCH 7B—122
ONE-WAY CLUTCH AND
CARRIER HUB ASSEMBLY 7B-126
3-4 CLUTCH 7B—128
2-3 ACCUMULATOR 7B—132
GOVERNOR ASSEMBLY
(G4A-HL) 7B-133
LOW AND REVERSE BRAKE 7B—134
2-4 BRAKE BAND 7B—135
BAND SERVO 7B—135
OTHER INSPECTION 7B—135
CONTROL VALVE BODY
(G4A-EL) 7B-136
CONTROL VALVE BODY
(G4A-HL) 7B-155
DIFFERENTIAL 7B—177
OUTPUT GEAR 7B—181
IDLE GEAR 7B—182
BEARING COVER ASSEMBLY 7B—185
BEARING HOUSING 7B—186
ASSEMBLY 7B-187
PRECATION 7B—187
ASSEMBLY-STEP 1 7B—187
ASSEMBLY-STEP 2 7B—197
ASSEMBLY-STEP 3 7B—202
ASSEMBLY-STEP 4 7B—208
INSTALLATION 7B—215
TORQUE SPECIFICATIONS 7B—215
HYDRAULIC CIRCUIT (G4A-EL) 7B—221
HYDRAULIC CIRCUIT (G4A-HL) 7B—239
76G07B-001