1987 MAZDA 626 Workshop Manual

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
ABS-9
Possible failure
Relay box, Hydraulic unit, Harness
Disconnect Q-01 (17-pin) connector. Disconnect battery. Turn ignition switch
ON.
Check continuity
at
harness side.
Q-01 (17-pin) Continuity
RY (B) BG (G) No

NG
OK

Check that resistance between
LO
(C)
of
harness side
and
ground changes when reversing
© and
© test-leads.
NG

Check relay box. (Refer
to
page 11—87.)

OK

Repair harness.
(Control unit—Relay box-Hydraulic unit)

NG
Replace relay box.

OK

Check continuity
at
harness side.
Q-01 (17-pin) Continuity
RY (B) Ground Yes

OK

Relay control unit.

NG
Disconnect Q-09 connector. Check continuity
at
motor side.
Q-09 Continuity
RY Ground Yes

NG
Repair harness. (Motor—Ground)

OK

Check continuity
at
motor side.
Q-09 Continuity
RY B Yes

NG
Replace hydraulic unit.

OK

Repair harness. (Control unit—Relay box-Hydraulic unit)

76G11X-056
11-81

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
86U11X-154
ABS-11
Possible failure
Relay box, Hydraulic unit, Harness
Disconnect Q-01 (17-pin) connector. Disconnect battery. Check continuity
at
harness side.
Q-01 (17-pin) Continuity
LO(C) BG (G) No

OK

Q-01 (17-pin) Resistance
BL (E) Ground Aoorox. 7512

OK

Replace control unit.
Check resistance
at
harness side.

NG
Check relay box. (Refer
to
page 11—87.)

OK

Repair harness. (Control unit—Relay box-Hydraulic unit)

NG

Q-08 Continuitv
BL Ground No

OK

Repair harness. (Control unit—Relay box-Hydraulic unit)

NG
Replace relay box.
Disconnect Q-08 connector. Check continuity
at
relay side.
NG
76G11X-057
86U11X-156
11-82

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
ABS-13
Possible failure
Relay box, Hydraulic unit, Harness
Check Q-10, Q-06, and Q-08 con-
nectors
for
proper connection.

OK

Q-01 (17-pin) Resistance
BL (E) BG (G) approx. 75
Q
OK

Q-01 (17-pin) Resistance
LO (C) © probe YG(J) © probe approx.
65 Q

Q-08 (6-pin) Q-08 (2-Din) Continuity
BG LR Yes

OK

Disconnect Q-09 and Q-08 (2-pin) connectors. Check continuity
at
harness side.
Q-09 Q-08 (2-pin) Continuity
RY RY Yes
Q-09 Continuity
RY I Ground No
Q-09 Resistance
RY B approx. 0.1
Si
NG

Disconnect Q-01 (17-pin) connector. Disconnect battery. Measure resistance at harness side.
NG

Check resistance between BL (C)
and
YG
(J)
of
harness side.

OK

Check continuity
at
hydraulic unit side.

NG
OK

Turn ignition switch ON.
Check continuity
at
harness side.
Repair connector.
Check relay box. (Refer
to
page 11 —87)

NG
Replace relay box.

OK

Repair harness.
(Control unit—Relay box
or
Ignition switch—Hydraulic unit)

NG
Repair harness. (Relay box—Battery)

NG
Repair harness. (Hydraulic unit—Relay box)

NG
OK

Replace hydraulic unit
Check relay box. (Refer
to
page 11—87.)

OK
Replace control unit.

NG

Replace relay box

76G11X-058
11-83

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
ABS-15
Possible failure
Control unit, Harness, Hydraulic unit
Disconnect Q-10 and Q-01 (17-pin and 11-pin) connectors. Check continuity
at
hydraulic unit side.
Q-10 Continuity
BR
|
Ground No

OK

Disconnect Q-06 connector.
Check continuity
at
hydraulic side.
Q-10 Continuity
BR Ground No
Q-06 Q-10 Resistance
Br
BW L
YG BR approx.
3 J)

YR YW

NG
NG
OK

Check Q-06 connector for proper connection.

| OK

Disconnect Q-06 connector. Meas-ure resistance
at
hydraulic unit side.

OK
NG

Replace hydraulic unit.
Repair harness. (Hydraulic unit-Control unit)
Replace hydraulic unit.

NG
Repair Q-06 connector.
Connect
Q-06 and Q-10 con-
nectors.
Check continuity
at
harness side.
Q-01 (17-pin) Continuity
Br (K) BW (0) L(R) YG(J) YR (M) YW (Q)
LO (C)
Yes
(Less than
100 Q)

NG
Repair harness.
(Control unit—Hydraulic unit)

OK
Replace control unit.

76G11X-095
11—84

ANTI-LOCK BRAKE SYSTEM
(ABS) 1 1

ABS-16
Possible failure
Control unit, Harness
Disconnect Q-01 (17-pin) and Q-10 connectors.
Check that hydraulic unit and har-ness resistance does not fluctuate when moving harness.
Q-01 17-pin) Q-10 Resistance
Br (K) BW
(0)
L(R) YG(J) YR (M) YW (Q)
BR Must
be
constant

NG
Repair connector
or
harness. (Q-01 (17-pin), Q-10)

OK
Replace control unit.

86U11X-160
ABS-17
Possible failure
ABS-17
Control unit
Replace control unit.

ABS-18
Possible failure
ABS-18
Control unit
Replace control unit.

86U11X-161

11-85

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
DIAGNOSIS INDICATION MODE
To obtain the diagnosis indication mode, proceed as
follows:
1. Remove the driver's seat.
2. Connect terminal wires (GB) and (B) of the check
connector (at control unit) with a jumper wire.
3. Start the engine.
Note
The system is now in the diagnosis indication
mode.
86U11X-162
4. Observe the warning light for illumination or count
flashing.
5. Connect an analog voltmeter to terminal wire (GR),
and count the times voltage is output.
Note
a) The voltmeter will fluctuate between OV and
approx. 12V.
b) Determine the failure and flow chart num-
ber with the Diagnosis Table. (Refer to page
11—75.)
76G11X-059
86U11X-164
86U11X-165
MEMORY CANCEL
Note
Failures are contained in the control unit mem-
ory. They are not erased when the battery is
disconnected. Follow the procedure below to
erase them.
1. Connect the terminal wires (GR) and (GB) of the
check connector with a jumper wire.
2. Turn the ignition switch ON.
3. Check that the warning light is illuminated, and wait
1—2 seconds.
4. Turn the ignition switch OFF.
5. Disconnect the jumper wire from terminal wire (GR).
6. Start the engine and wait for the warning light to
go OFF.
Note
a) One failure memory is erased each time the
above steps are taken.
b) If the warning light illuminates or blinks af-
ter step 6, read and note diagnosis indica-
tion. The memory has the capacity for
storing 32 failures.
7. Turn the ignition switch OFF.
8. Remove the jumper wire.
11-86

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
86U11X-1C
Q-08
Q-08
Fail-safe relay
B B BG
(Q-08)(Q-09)

V
BL BR
Motor relay
B BR (Q-09)
LO RY
View from male-pin side
86U11X-167
76G11X-096
ABS WARNING LIGHT
Inspection for No Illumination
1. Check that other warning lights illuminate. If not,
check the METER 10A fuse for burning out.
2. Turn the ignition switch ON.
3. Ground the LY terminal
of
the check connector with
a jumper wire.
4. Check that the ABS warning light illuminates.
If not illuminated, check the bulb and harness (bat-
tery -» check connector).
5. Check for 12V at F (LY) terminal of the control unit
connector.
If the voltage is not as specified, check the harness
(bulb control unit).
If the voltage is as specified, replace the relay box
and the control unit.
RELAY BOX
Inspection of Fail-safe Relay
1. Check for continuity of the relay with an ohmmeter.
Replace the relay box if necessary.
Connecting to BR B (Q-08) B (Q-09) 12V Ground BR B (Q-08) B (Q-09)
— — O— —O
BG BL O— —O
O—O: Indicates continuity
2. Check that the resistance between terminal wire
(BR) and terminal wire (LY) changes when revers-
ing the © and © test-leads. Replace the relay
box if necessary.
Inspection of Motor Relay
1. Check for continuity of the relay with an ohmmeter.
Replace the relay box if necessary.
Connecting to RY B (Q-09) 12V Ground RY B (Q-09)
-—
BR LO o— O
O—O: Indicates continuity
2. Check that the resistance between terminal wire
(BR) and terminal wire (LO) changes when revers-
ing the © and © test-leads. Replace the relay
box if necessary.
WHEEL SPEED SENSOR
Inspection
1. Measure the resistance of the sensor with an
ohmmeter.
Resistance: 800—1,200 0
2. If the resistance is not within specification, replace
the sensor.
3. Check that the harness is not twisted and does not
contact other objects when turning the steering
wheel is turned fully.
11-87