1987 MAZDA 626 brake sensor

CONTROL SYSTEM 4C
7. Make sure that the throttle valve is fully closed.
8. Check that the BLUE wire voltage is within the
specified range.
9. Adjust the throttle sensor if necessary
76g04c-191
10. Open the throttle valve fully.
11. Check that BLUE wire voltage is within the speci-
fied range.
12. If not correct, replace the throttle sensor.
76g04c-192
13. Turn the ignition switch OFF.
14. Disconnect the SST and reconnect the throttle sen-
sor connector.
15. Disconnect the negative battery terminal and de-
press the brake pedal for 5 seconds to eliminate
the malfunction memory from the control unit.
76g04c-193
Adjustment
1. Perform steps 1 to 7 in the inspection procedure.
2. Connect the voltmeter to the BLUE wire.
3. Loosen the throttle sensor mounting screw.
76G04C-194
4C-105

4C CONTROL SYSTEM
4. Make sure that the throttle valve is fully closed.
5. Turn the throttle sensor so that the BLUE wire volt-
age indicates within the specified closed range.
6. Tighten the throttle sensor mounting screw.
7. Recheck that the BLUE wire voltage is within the
specified range.
76G04C-195
8. Turn the ignition switch OFF.
9. Disconnect the SST and reconnect the throttle sen-
sor connector.
10. Disconnect the negative battery terminal and de-
press the brake pedal for 5 seconds to eliminate
the from the malfunction memory from the control
unit.
76G04C-196
76G04C-198
4C-106
IDLE SWITCH
Inspection
1. Disconnect the idle switch connector.
2. Check continuity between the switch and a ground.
Throttle valve condition Continuity
Fully closed Yes
Open No
3. If not correct, check condition of the wiring harness
of the idle switch. Replace the idle switch and throt-
tle body as an assembly, if necessary.
WATER THERMO SWITCH
Inspection
1. Remove the switch from the radiator.
2. Place the switch in water with a thermometer and
heat the water gradually.
3. Check for continuity of the switch with an
ohmmeter.
Coolant temp. Continuity
More than approx. 17°C (63°F) Yes
Less than approx. 10°C (63°F) No
4. If not correct, replace the water thermo switch.

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

7B TROUBLESHOOTING (G4A-EL)

ON VEHICLE-
-f-
—OFF VEHICLE

\ Inspection point
and

\ reference page

Condition
•

Electronic control system Prelim-
inary
Hydraulic
control
system
Power train \ Inspection point
and

\ reference page

Condition
•
7B-66

m CO I m r--
7B-63

i
cn to I m
Section

4B

|

Section

4B

|

ID to i m
CO CO 1 CD
7B-68
|
en CO 1 IX)
to 1 00 r-.
cn CD 1 CO
7B-69
|

1 CD r--
i no
cn s-1 m
Section
4B

r*-cn
S-1 CD h-
"=1-
rJ CO
7 CD r-
(XI o
1 m
cn CM 1 CD
7B-107

|
CD
7 CD 7 m
I
7B-113
I
CO CM
7 CO r-.
m cn
7 CO r-.
cn
7 DO r-
CM CM
7 CO

|
7B-126

7 00 r-
CO 7 cn
1*-r*-
7 m r-
\ Inspection point
and

\ reference page

Condition
•
Brake

light
switch

|

Inhibitor

switch

|

Mode

switch

|

1
CO. •o o X
Idle

switch

Throttle

sensor

|

Water

temp,

switch

|
0 tn c 0) cn
s
ffi
Q tn 01 o Hi >
Pulse

generator

|

"a o c 0) a to CM
TJ O CL ID s CO C\l 3-4

solenoid

|

Lock-up
solenoid

I

ATF

level
and
condition

|

Selector

lever

m Xj CO CJ 03
1 sz
Idle
speed
and
Ignition
timing

Control

valves

Accumulators
Oil
pump
Hydraulic

circuit

Torque

converter

Forward

clutch
Coasting
clutch

Reverse

clutch
JT O
u TT ro 2-4

brake
band
and

servo
$ 2
B cn cii > £ "O C CO
o
XI y
o >. CO S cb a O
One-way

clutch

2

s CI Cn tz JC 5 0-
Planetary

gear

Differential

assembly
Accelerating

Vehicle does
not
move
in
D,
S,
L,
or R
range
O O O O O O O O O O 0

Accelerating

Vehicle moves
in N
range -0 0 -—

Accelerating
Excessive creep
-0 O O -—

Accelerating
No creep
at all
O o o o
o
G 0 O O

Shifting

|

No shift
O O o
o
0 O 0 0
o
o O

Shifting

|
Abnormal shift sequence
0 o O O 0
o
o 0 O o o 0 O

Shifting

|
Frequent shifting 0 o 0 0 o 0 O O 0

Shifting

|

Excessively high
or
low
shift point 0 o 0 O 0 0 o 0 O 0 0
Shifting

|

No lock-up
0 o 0 0 o 0 O O o O

Shifting

|

No kick-down o o o o

Slipping

Engine
run
away
or
slip when
starting vehicle 0 o 0 O o O

Slipping
Engine
run
away
or
slip when
up-
or
down-shifting o o o 0 o O 0 0 O
8 n cn 4S SI V)
Excessive
N to D or N to R

shift shock o O o o o O
8 n cn 4S SI V)
Excessive shift shock when
up-

shifting
or
downshifting o o o o 0 0 0 8 n cn 4S SI V) Excessive shift shock when
changing range 0 0 o 0 o

j
Noise

Transaxle noisy
in N or P

range o o 0 O

j
Noise

Transaxle noisy
in D, S, L,
or

R range o 0 0 O

I
Others

j

No engine braking o O o 0 o o

I
Others

j

No mode change o 0 o o o o o o o
O
o
0

I
Others

j
Transaxle overheats
o o
0 o 0 o 0

I
Others

j
Vehicle moves
in
"P",
or
park-ing gear
not

disengaged when
"P"
is
dis-
engaged
0 O

I
Others

j

Hold indicator flashes o
0
o
0
o
O
o — — —
I
Others

j

Engine will
not
start
o
o
O — — —
76G07B-014
7B—14

TROUBLESHOOTING (G4A-EL) 7B
79G07C-068

Drive at 50
km/h
(31
mph)
Kick-down
Stop
the
vehicle
79G07C-069
After-repair Procedure
1. Cancel the memory of malfunctions by disconnect-
ing the negative battery terminal for at least five sec-
onds, then reconnect it.
2. Remove the EC-AT tester if it is connected.
3. Drive the vehicle at 50 km/h (31 mph), then de-
press the accelerator pedal fully to activate kick-
down. Stop the vehicle gradually.
KICK goimsv
BRAKE LIGHTS*
CRUISE CONTROL
C V,. DEPRESS FULL*
Ox
azsa
ORUti rpn
"J
i"
•
rm uu

£ZL ofF

4. Reconnect the EC-AT tester to the 6-pin service
connector.
5. Ground the 1 -pin service connector with a jumper
wire.
6. Turn the ignition switch ON.
7. Check that no code numbers are displayed.
79G07C-070
Inspection Procedure
No. 06 code display (Vehicle speed sensor)
76G07B-017
7B-19

TROUBLESHOOTING (G4A-EL) 7B
Item Indication Condition Possible cause
BRAKE LIGHT SW ON Brake pedal depressed Brake light switch or
wiring BRAKE LIGHT SW
OFF Brake pedal released
Brake light switch or
wiring
WATER TEMP SW ON Coolant temperature 72°C (162°F) or above Water temp switch or wiring WATER TEMP SW
OFF Coolant temperature lower than 65°C (149°F)
Water temp switch or wiring
ATF TEMP SW ON ATF temperature 150°C (302°F) or above Fluid temperature switch or wiring ATF TEMP SW
OFF ATF temperature lower than 143°C (289°F)
Fluid temperature switch or wiring
CRUISE CONTROL SW Not used — —
Input (Digital display)
THROTTLE SENSOR
EC-AT control unit terminal voltage All the time Throttle sensor, idle switch or wirings
VEHICLE SPEED*
Vehicle speed calculated from speed sensor signal
All the time Vehicle speed sensor, speedometer cable, or wiring
DRUM SPEED* Drum speed All the time Pulse generator or wirings
Output (Light)
1-2 SOLENOID VALVE*
ON
Refer to page 7B—26 solenoid valve operation table
Control unit, 1-2 shift sol., or wiring 1-2 SOLENOID VALVE* OFF
Refer to page 7B—26 solenoid valve operation table
Control unit, 1-2 shift sol., or wiring
2-3 SOLENOID VALVE*
ON Refer to page 7B—26 solenoid valve operation table Control unit, 2-3 shift sol., or wiring 2-3 SOLENOID VALVE* OFF
Refer to page 7B—26 solenoid valve operation table Control unit, 2-3 shift sol., or wiring
3-4 SOLENOID VALVE*
ON
Refer to page 7B—26 solenoid valve operation table
Control unit, 3-4 shift sol., or wiring 3-4 SOLENOID VALVE* OFF
Refer to page 7B—26 solenoid valve operation table
Control unit, 3-4 shift sol., or wiring
LOCK-UP SOLE-NOID VALVE*
ON Lock-up condition Control unit, lock-up sol., or wiring LOCK-UP SOLE-NOID VALVE* OFF Non-lock-up condition
Control unit, lock-up sol., or wiring
HOLD INDICATOR ON Hold mode Control unit, Hold switch, or wiring HOLD INDICATOR OFF Other modes
Control unit, Hold switch, or wiring
MODE INDICATOR ON Power or economy mode Control unit, hold switch, mode switch, or wiring MODE INDICATOR
OFF Hold mode
Control unit, hold switch, mode switch, or wiring
NO LOAD SIGNAL Not used — —
76G07B-028
7B-25

7B TROUBLESHOOTING (G4A-EL)
STEP 7 (ROAD TEST)
This step is performed to inspect for problems at the various ranges. If these tests show any problems,
adjust or replace by referring to the electronic system component or mechanical sections.
Caution
Perform the test at normal ATF operating temperature (50—80°C, 122—176°F).
D Range Test
Shift point, shift pattern, and shift shock
1. Shift the selector lever to D range and select the Power mode.
2. Accelerate the vehicle with half and full throttle valve opening.
Note
Throttle sensor voltage of the EC-AT Tester represents the throttle valve opening.
3. Check that 1-2, 2-3 and 3-OD up-shifts and downshifts and lock-up are obtained. The shift points
must be as shown in the D range (Power) shift diagram.
Note
a) Drum speed (rpm) of the EC-AT Tester represents the shift point.
b) Vehicle speed of the EC-AT Tester and speedometer and vehicle speed on a chassis
roller may not meet the specified shift pattern because of tire size. Therefore, check
the shift points with the Drum speed.
c) There is no lock-up when the coolant temperature is below 72°C (162°F).
d) There is no overdrive when the cruise control is operating and there is a 3 km/h (1.9
mph) difference between the pre-set cruise speed and vehicle speed, or set or resume
switch is ON.
e) There is no lock-up when the brake pedal is depressed.
4. Check the up-shifts for shift shock or slippage in the same manner.
5. While driving in OD, shift the selector lever to S range and check that 4-3 downshift immediately
occurs, then decelerate and check that engine braking effect is felt in only 3rd gear.
7B—34

7B TROUBLESHOOTING (G4A-EL)
Evaluation
Condition Possible Cause
No 1-2 up- or down-shift Stuck 1-2 shift solenoid valve
Stuck
1
-2 shift valve
No 2-3 up- or down-shift Stuck 2-3 shift solenoid valve Stuck 2-3 shift valve
No 3-OD up- or down-shift Stuck 3-4 shift solenoid valve Stuck 3-4 shift valve
No lock-up shift Stuck lock-up control solenoid valve Stuck lock-up control valve
Incorrect shift point Mis-adjusted throttle sensor Sticking shift valves
Excessive shift shock or slippage
Excessive shift shock Stuck accumulators Stuck or no one-way check orifice
Worn clutches, brakes, or one-way clutch
No engine braking effect Worn clutches or brakes
76G07B-035
Noise and vibration
Drive the vehicle in OD (lock-up), OD (no lock-up), 3rd (Hold) and check for abnormal noise or vibration.
Note
Abnormal noise and vibration can also be caused by the torque converter, drive shaft, or
differential. Therefore, checking of cause must be made with extreme care.
Kick-down
Drive the vehicle in OD, 3rd and 2nd gears and check that kick-down occurs for OD->3, OD->2, OD->1,
3->2, 3-+1, 2-> 1, and the shift points are as shown in the shift diagram.
S Range Test
Shift pattern
1. Shift the selector lever to S range and select the Economy mode.
2. Accelerate the vehicle and check that 1-2 and 2-3 up-shifts and down-shifts are obtained, and that
no overdrive and no lock-up are obtained.
Note
a) Inspections of shift shock and shift point are not necessary because these are the same
as those of the D Range Test.
b)ln S range, the shift patterns for Economy and Power modes are the same.
c) Shift points are the same as those of the D range (Power) shift diagram.
3. While driving in S range (Economy mode) and 3rd gear, select the Hold mode and check that 3rd
gear is held until the 3-2 down-shift point as shown in the S range (Hold) shift diagram is achieved.
4. Accelerate the vehicle with S range (Hold mode) and check that 2nd gear is held.
7B i—36