1987 MAZDA 626 brake

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
Removal of Rear Sensor Rotor
1. Loosen the rear wheel lug nuts.
2. Block the front wheels.
3. Jack up the rear of the vehicle and support it with safety stands.
4. Remove the wheels.
5. Remove in the sequence shown in the figure, referring to removal note for the specially marked parts.
86U11X-182
1. Hub cap
2. Locknut
3. Caliper assembly and
mounting support
4. Disc plate
5. Sensor rotor
Removal note
Sensor rotor
Remove the sensor rotor from the hub assembly with
the SST.
86U11X-183
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ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
Installation of Rear Sensor Rotor
Install in the reverse order of removal, referring to installation note for the specially marked parts.
Torque specifications
86U11X-184
Installation
Sensor rotor
Press the sensor rotor onto the hub with the SST.
86U11X-185
Locknut
1. Install and tighten the locknut.
2. Stake a new locknut securely in the driveshaft
groove.
Caution
Do not use a pointed tool for staking.
3. Check that the hub rotates freely by hand.
86U11X-186
11—93

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
HYDRAULIC UNIT FLUID
Inspection of Level
1. Run the engine for 10 seconds to let the pump mo-
tor build pressure in the accumulator; then stop the
engine.
2. Check that the fluid level is between the Max and
Min lines of the reservoir.
3. If the level is lower than the Min line and leakage
from cap is not found, replace the hydraulic unit
assembly.
86U11X-187
76G11X-061
Replacement
1. Remove the reservoir cap and retainer.
2. Use a suction pump and a soft vinyl hose to suck
fluid from the reservoir.
Caution
a) A hard hose may damage the filter in the
reservoir.
b)Only the amount of fluid shown can be re-
moved from the reservoir.
3. Fill the reservoir with the specified type and amount
of brake fluid.
Caution
a) Do not allow any foreign material to enter
the reservoir.
b) Do not soak the upper filter with brake flu-
id. Otherwise, pouring fluid may be difficult.
Fluid: DOT-3 or DOT-4 or SAE J1703
4. Check the fluid level as described above.
HYDRAULIC UNIT
Warning
The accumulator contains high-pressure gas;
do not attempt to disassemble it or subject it
to hard shocks or high heat.
When the hydraulic unit is scrapped, the high-
pressure gas must be released. Turn the
screw on the accumulator bottom one full turn
only and allow the gas to escape gradually.
76G11X-097
11—94

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
86U11X-190
86U11X-191
76G11X098
Inspection of Pressure Reduction
1. Check that the battery is fully charged.
2. Jack up the vehicle and support it with safety
stands.
3. Release the parking brake.
4. Check the wheel for brake drag while turning it by
hand.
5. Connect terminal wires (GB) and (B) of the check
connector with a jumper wire.
6. Have an assistant depress the brake pedal; then
verify that the wheel cannot be turned.
7. Run the engine for 10 sec, and stop it.
8. With the brake pedal depressed, turn the ignition
switch ON.
9. With the brake pedal still depressed, check that the
wheel can be turned intermittently (when pressure-
reduction is operating).
Right'F Left F Rear Pressure reduction
Ignition switch ON OFF
1 05 1 sec sec sec
J
10. Check operation at the remaining wheels.
11. If not operated correctly, check the warning light
and brake light switch circuit for proper operation.
Inspection of Proportioning Valve
Note
The proportioning valve is built into the hy-
draulic unit.
1. Disconnect the flexible hose from the brake pipe;
then connect one pressure gauge to the front brake
pipe, the other to the rear brake pipe.
Note
Use a pressure gauge [9,810 kPa (100 kg/cm2,
1,422 psi)].
86U11X-193
11—95

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
t
2. Bleed air from the system.
3. Depress the brake pedal, and compare the fluid
pressure of the front brake with that of the rear
brake.
Fluid pressure kPa (kg/cm2, psi)

Front brake side Rear brake side
A 2,943 (30,427)
A'
2,747-3,139
(28-32, 398-455)

A B
B 6,867 (70,995)
B'
3,924-4,316 (40-44, 569-626)

Front brake pressure kPa (kg/cm2, psi) 4. If the measurement is not within specification re-
place the hydraulic unit assembly. 86U11X-194
REMOVAL
Caution
a) Brake fluid will damage painted surfaces. If it does get on the painted surfaces, wipe
it off immediately.
b) Oo not tip the hydraulic unit to prevent the brake fluid in the reservoir from draining.
1. Remove the nuts mounting the fuel filter and ignitor to the bracket and move them toward the engine.
2. Remove the air cleaner assembly.
3. Remove the master cylinder. (Refer to page 11—14.)
4. Remove the hydraulic unit in the sequence shown in the figure.
76G11X-062
11—96

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
86U11X-196
1. Coupler
2. Brake pipe (from master cylinder)
3. Brake pipe (to front brakes)
4. Brake pipe (to rear brakes)
5. Mount bushing
6. Hydraulic unit
11—97

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
INSTALLATION
1. Install in the reverse order of removal.
Before installing the air cleaner assembly, igniter, and fuel filter:
(1) Add brake fluid and bleed air. (Refer to page 11—9.)
(2) Check each part for fluid leakage.
(3) Check the brake fluid level of both the master cylinder reservoir and hydraulic unit reservoir.
2. Tighten all bolts and nuts to the specified torque, referring to torque specifications.
3. After installation:
(1) The sealing reservoir cap (red) is installed on the new hydraulic unit to prevent the brake fluid
from leaking while shipping. Replace it with an original cap (black) after replacing the hydraulic unit.
(2) Check that the hydraulic unit operates properly by testing the pressure reduction. (Refer to page
11-95.)
Torque specifications
11-98

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
CONTROL UNIT CIRCUIT
Inspection of Control Unit Circuit
1. Start the engine, and run it for 10 seconds.
2. Disconnect the connectors from the control unit. Check the connector at the harness side as shown
in the table below.
Terminal Connection or measured item Check item Tester connection Condition Voltage or
resistance

Q-01 11 -pins
2A (W),
2B (R)
Wheel speed sensor
Left front Voltage (AC) 2A (W)
- 2B
(R) Turn wheel
1
revolution
per second More than 0.25V (AC)
Q-01 11 -pins
2A (W),
2B (R)
Wheel speed sensor
Left front
Resistance
2A (W)
- 2B
(R)

—
800-1.2000
Q-01 11 -pins
2C (Y),
2D
(0)
Wheel speed sensor
Right front Voltage (AC) 2C (Y)
-
2D (0) Turn wheel
1
revolution
per second More than 0.25V (AC)
Q-01 11 -pins
2C (Y),
2D
(0)
Wheel speed sensor
Right front
Resistance
2C (Y)
-
2D (0)

—
800-1,2000
Q-01 11 -pins 2E (YG),
2F (YL)
Wheel speed sensor
Left rear Voltage (AC) 2E (YG)
- 2F
(YL) Turn wheel
1
revolution
per second More than 0.25V (AC) Q-01 11 -pins 2E (YG),
2F (YL)
Wheel speed sensor
Left rear
Resistance
2E (YG)
- 2F
(YL)

—
800-1,200G
Q-01 11 -pins
2H (G).
2J
(L)

Wheel speed sensor
Right rear Voltage (AC) 2H (G)
- 2J
(GR)
Turn wheel
1
revolution
per second More than 0.25V (AC)
Q-01 11 -pins
2H (G).
2J
(L)

Wheel speed sensor
Right rear
Resistance
2H (G)
- 2J
(GR)

_
800-1,200fl
Q-01 11 -pins
21 (GR) Low pressure switch Continuity 21 (GR)
-
Ground
—
Continuity
Q-01 11 -pins
2K (LB) High pressure switch Continuity 2K (LB)
-
Ground
—
Continuity
Q-01 11 -pins
2L (WB) Alternator output Voltage 2L (WB)
-
Ground Run engine Approx.
14V

Q-01
17-pins
A (WG) Brake light switch Voltage A (WG)
-
Ground Depress brake pedal 12V
Q-01
17-pins
B (RY) Motor Continuity B (RY)
—
Ground
—
Continuity
Q-01
17-pins
C (LO) Motor relay Resistance C (Lo)(© test-lead)-J
—
Approx. 60—700
Q-01
17-pins
D (GR) Check connector Continuity D (GR)
- A
(GR, Q-07)
—
Continuity
Q-01
17-pins
E (BL) Fail-safe relay Resistance E (BL)
- G
(BG)
—
Approx. 70-800
Q-01
17-pins
F (LY) Warning light Continuity F (LY)
-
Ground
—
Continuitv Q-01
17-pins G (BG) Battery Voltage G (BG)
—
Ground Turn ianition
SW ON
12V Q-01
17-pins H (GB) Check connector Continuitv H (GB)
- B
(GB. Q-07)
—
Continuitv
Q-01
17-pins
J (YG) Solenoid valve
Resistance
JfYG)
- K
(Br)

-
Approx.
5.5—7.00
Q-01
17-pins
K (Br) Solenoid valve
Resistance
JfYG)
- K
(Br)

-
Approx.
5.5—7.00
Q-01
17-pins
M (YR) Solenoid valve Resistance M (YR)
- 0
(BW)
-
Approx.
5.5—7.00
Q-01
17-pins
0 (BW) Solenoid valve Resistance M (YR)
- 0
(BW)
-
Approx.
5.5—7.00
Q-01
17-pins
Q (YW) Solenoid valve
Resistance
Q (YW)
- R
(L)

-
Approx.
5.5—7.00
Q-01
17-pins
R (L) Solenoid valve
Resistance
Q (YW)
- R
(L)

-
Approx.
5.5—7.00
Q-01
17-pins
L (B)
Ground circuit Continuity
L (B)
—
Ground
Continuity
Q-01
17-pins
N
(B)
Ground circuit Continuity N (B)
—
Ground Continuity
Q-01
17-pins
P (B)
Ground circuit Continuity
P (B)
—
Ground
C (B.Q-07)
-
Ground
Continuity
4-pins C(B)
Ground circuit Continuity
P (B)
—
Ground
C (B.Q-07)
-
Ground
Continuity

Control Unit Connector View from harness side
Q-01 (11-pin)

LB
GR YG Y W
>1 ,1 U;.l Ki -X
1 L G VL rf
Q-01 (17-pin)
Q-01 ABS Control Unit [R]
YW BW YR Br 8G BL LO WG
icL olL
MIL
ICL G(=L tl ij^" llyl
>1
CjJ
Lt|J JCjJ fiC|3 H«|3
L B B B ffi SB L* GS RY
Check connector (4-pin)
Q-07 Check Connector [RJ
B GR
LY GB
86U11X-199
11—99