check engine light MAZDA 626 1987 Owner's Guide

1 0 4-WHEEL STEERING GEAR AND LINKAGE
(Example) ^"in)
-I
8 mm (0.31 in)
1 1111111
- ^Center
10 mm (0.39 in)
86U10X-309
(8) The center position can be determined from
the left/right measurements in (5) and (7) above.
Example:
Right rotation.... 10 mm (0.39 in)
Left rotation....8 mm (0.31 in)
Center = Right 1 mm (0.04 in)
(9) Check that the center is within specification.
Specification
= R 5 mm (0.4 in ) to L 5 mm (0.4 in)
(10) If not correct, adjust the steering angle trans-
fer shaft.
2. Steering Inspection
With the vehicle stopped and the engine running,
check that the rear wheels turn in the opposite
direction when the steering wheel is turned and that
there is no abnormal noise.
86U10X-310
3.4WS Electric System Inspection
Drive the vehicle and check that the 4WS warning
light does not come on at over 40 km/h (25mph).
86U10X-311
10—34

1 0 ELECTRICAL COMPONENTS OF ELECTRONICALLY-CONTROLLED POWER STEERING (ECPS)
76G10X-020
76G10X-021
Checking Condition
Condition A
1. Turn the ignition switch OFF.
2. Start the engine and let it idle.
3. Turn the steering wheel to the straight-ahead po-
sition, and check the output pattern.
Refer to page 10—89 for other patterns and indi-
cated failure points.
Condition B
1. Turn the ignition switch OFF.
2. Start the engine and let it idle.
3. Turn the steering wheel 45° left and right from the
center, and check the output pattern.
Refer to page 10—89 for other patterns and indi-
cated failure points.
Condition C
1. Turn the ignition switch OFF.
2. Place the vehicle on a chassis roller tester. Block
the rear wheels, and secure it with chains.
3. Start the engine. Put the transmission in gear and
operate the vehicle at more than 10 km/h (6.2
mph).
4.Check the output pattern.
76G10X-022
Normal pattern
4 4V
Normal pattern Normal pattern
uV
Refer to page 10—90 for other patterns and indi-
cated failure points.
Note
For vehicles equipped with ABS, the ABS
warning light may come on. This is not a fail-
ure. The light will go off when turning the ig-
nition switch OFF and back ON.
86U10X-213
10—88

ELECTRICAL COMPONENTS OF 4-WHEEL STEERING 1 0
TROUBLESHOOTING GUIDE
Self-Diagnosis Function
The four-wheel steering (4WS) control unit contains a self-diagnosis function to detect malfunctions
within itself, the 4WS electrical components and circuits.
If a malfunction is detected, the control unit indicates where the problem is located and the 4WS warn-
ing light in the instrument cluster will flash for one minute with a specific pattern,
Troubleshoot the 4WS system according to the following flow chart.
Symptom of problem
76G10X-026
TROUBLESHOOTING
Checking Condition
Condition A
1. Turn the ignition switch OFF.
2. Start the engine after the ignition switch has been
OFF for at least 10 seconds, and check if the 4WS
warning light flashes or illuminates within 60
seconds.
3.
If
flashing or illumination occurs, inspect the circuit.
(Refer to page 10—95.)
76G10X-027
10—95

1 0 ELECTRICAL COMPONENTS OF 4-WHEEL STEERING
Condition B
1. Place the vehicle on a chassis roller tester. Block
the rear wheels, and secure it with chains.
2. Turn the ignition switch OFF.
3. Start the engine after the ignition switch has been
OFF for at least 10 seconds. Put the transmission
in gear and operate the vehicle at more than 40
km/h (25 mph).
4. Check if the 4WS warning light flashes or il-
luminates within 60 seconds.
5.
If
flashing or illumination occurs, inspect the circuit
by referring to the table below.
76G10X045
Diagnosis Output Pattern
Warning light output pattern
0.5 sec —i 2.5 sec
Malfunction
Normal operation, control unit or wir-ing harness
Speed sensors or
wiring harness
Flow chart
No.
4WS—0
4WS—1
Rear steering gear
assembly
Solenoid valve or wiring harness
Stepper motor or wiring harness
Rear-to-front steer-ing ratio sensor or wiring harness
4WS—2
4WS—3
4WS—4
4WS—5
86U10X-225
10-96

1 0 ELECTRICAL COMPONENTS OF 4-WHEEL STEERING
4WS-0 Normal operation or failure of con-trol unit or harness
Start engine.
Disconnect R-01 (7-pin) connector. Check that 4WS warning light flashes or illuminates.
NG
Repair harness. (Fuse box to Control unit or Control unit to Body ground).
YES No electrical problem.
NO
Reconnect connector.
Check voltage between terminals and body ground.
Terminal Voltage
G(B) OV
H(B) OV
K(G) Approx. 12V
L(G) Approx. 12V
N(B) OV
OK Replace control unit.
4WS-1 Failure of speed sensors or wiring
harness
Check speed sensor at transaxle. (Referring to page 10—103)
OK
NG Replace speed sensor.
Check for continuity between terminal of transaxle speed sensor and R (O) terminal of the control unit connector.
NG^ Repair wiring harness (Control unit to Transaxle
speed sensor).
Cont'd 76G10X-028
10—98

1 0 ELECTRICAL COMPONENTS OF 4-WHEEL STEERING
flashes
Replace control unit
4WS-9 Failure of control unit, alternator, or wiring harness
Start engine,
I
Check voltage between terminal of control unit con-nector and body ground.
Terminal Voltage
G(B) OV
H (B) OV
K(G) Approx. 12V
L (G) Approx. 12V
N(B) OV
OK
NG
Check 4WS relay and timer (Refer to page 10—103) -
OK
Check battery, harness, and alternator.
NG
Turn ignition switch OFF. Start engine. Check if 4WS warning light flashes or illuminates.
NO
Momentary problem (If warning light often flashes or illuminates, check battery and alter-nator. Replace control unit if necessary).
YES
Replace control unit.
Replace relay and timer
76G10X-031
4WS WARNING LIGHT
1. Turn the ignition switch OFF.
2. Turn the ignition switch ON, and check that the
4WS warning light illuminates.
3. If there is no illumination, check the warning light
bulb and wiring harness.
Replace the control unit if necessary.
86U10X-232
10-102

POWER BRAKE UNIT 1 1
86U11X-038
0
o
X
\ V^ Third
Second
^ First
86U11X-039
O X

fiSy

V
86U11X-040
Pedal-depression Pre!tur!9au9e
force gauge
^Intake manifold
86U11X-041
POWER BRAKE UNIT
FUNCTION CHECK
Simple Method
First step
1. With the engine stopped, depress the pedal a few
times.
2. With the pedal depressed, start the engine
3. If immediately after the engine starts the pedal
moves down slightly, the unit is operating.
Second step
1. Start the engine.
2. Stop the engine after it has run for
1
or 2 minutes.
3. Depress the pedal with the usual force.
4.
If
the first pedal stroke is long and becomes short-
er with subsequent strokes, the unit is operating.
5. If a problem is found, inspect for damage of the
check valve or vacuum hose, and examine the in-
stallation condition. Repair if necessary, and inspect
it once again.
Third step
1. Start the engine.
2. Depress the pedal with the usual force.
3. Stop the engine with the pedal still depressed.
4. Hold the pedal down for about 30 seconds.
5. If the pedal height does not change, the unit is
operating.
6. If there is a problem, check for damage to the
check valve or vacuum hose, and check the con-
nection. Repair if necessary, and check once
again.
If the nature of the problem is still not clear after fol-
lowing the 3 steps above, follow the more detailed
check described in "Method using tester".
Method Using Tester
Connect a pressure gauge, vacuum gauge, and ped-
al depression force gauge as shown in the figure. Af-
ter bleeding the air from the pressure gauge, conduct
the test as described in the 3 steps below.
Note
Use commercially available gauges and ped-
al depression force gauge.
11—27

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
TROUBLESHOOTING
Precaution
Conditions that are not malfunctions
1. It may happen that vibration is felt in the steering wheel, body, and/or brake pedal when the ABS
is functioning; such vibration is simply an indication that the system is functioning.
2. Sound of the pump motor operating, accumulator pressure being released, or the relay operating
may be heard from the engine compartment when the engine is started as the system is being auto-
matically checked.
3. The ABS pump motor may be automatically activated even though the ABS is not operating.
4. The ABS warning light may illuminate under any of the following conditions:
• When the vehicle is traveling on snow or ice with the parking brake activated or a brake dragging
at one wheel.
• When different-sized tires are used.
• When tires of different gripping performance are used.
• When (while the vehicle is jacked up or stuck) only the front wheels are spun for 20 seconds or more.
• When there is insufficient battery voltage.
Note
Under the above conditions, the warning light will not illuminate a second time when the
ignition is switched OFF then back ON, and there will be no memory entry to the control
unit of a problem.
Troubleshooting notes
The ABS is composed of electrical components, mechanical components (hydraulic unit), and the com-
ponents of the standard brake system.
Fundamentally, malfunction of the ABS electrical or mechanical components is judged by the self-
diagnosis function within the ABS control unit. And malfunctions are indicated by the warning light
in the instrument panel.
The location
of
a malfunction is indicated by the technician switching the system to the diagnosis-indication
mode.
The self-diagnosis and indication functions must be used when malfunctions of the ABS are being
diagnosed.
76G11X-091
11—73

1 1 ANTI-LOCK BRAKE SYSTEM (ABS)
Troubleshooting Main Flow Chart
Check that the ABS warning light operates.

• Turn ignition switch OFF
to
ON, and check that ABS warning light illuminates constantly.

Flashing (Past failure)
OK
Check the ABS for failure.
• Start engine, and observe flashing
of
warning light.
Does not
illuminate
constantly
Warning light Possible cause
Does
not il-

luminate
at all

Refer
to
page 11—86.

ON
Alternator
L
ter-minal output Wiring harness (ALT-control unit) Control unit

OFF
1 sec

Alternator
L
ter-minal output Wiring harness (ALT-control unit) Control unit

ON
Relay box wiring harness (warning light-control unit) Control unit

OFF
1 sec

Relay box wiring harness (warning light-control unit) Control unit

No illumination
(Not diagnosed)
Illuminates constantly
(Present failure)
ABS is usually operating cor-rectly.
Consult table below when ABS failure
is
still suspected.
System Possible cause
ABS Brake light switch
Both rear wheel speed sensors
Control unit Proportioning
valve
in hy-
draulic unit
Other than Refer
to

ABS troubleshoot-ing guide
on

page 11—5.

Repair failures with flow
chart. (Refer to page
11—76.)
76G11X-054
11-74

ANTI-LOCK BRAKE SYSTEM (ABS) 1 1
Diagnosis Table
Note
Flashing of the warning light shows past failure, and its illumination shows present failure.
Diagnosis indication Possible failure Flow chart
No. Warning light Voltmeter Possible failure Flow chart
No.
ON
n
i2vn
OV

Hydraulic unit Harness
Right front wheel speed
sensor ABS-1
ON
n nn
Hydraulic unit Harness Left front wheel speed sensor ABS-2

OFF

Hydraulic unit Harness Left front wheel speed sensor ABS-2

OFF
nnn

Hydraulic unit Harness
Rear wheel speed sensor ABS-3

n
nnnn
Right front sensor rotor ABS-4

n
nnnnn
Left front sensor rotor ABS-5

JLilTUITLTL
Right rear sensor rotor ABS-6

jirLruiJum
Left rear sensor rotor ABS-7

J n
Hydraulic unit Harness
Control unit connector (11-pin)
ABS-8

nnnn

Hydraulic unit Harness
Control unit connector (11-pin)
ABS-8

J nn

Relay box
Hydraulic unit
Harness
ABS-9

jumruiTL

Relay box
Hydraulic unit
Harness
ABS-10

j nnn
Relay box
Hydraulic unit
Harness
ABS-11

jinnjuuL

Relay box
Hydraulic unit
Harness ABS-12

j nnnn

Relay box
Hydraulic unit
Harness
ABS-13

jiruuirirL

Relay box
Hydraulic unit
Harness
ABS-14

j nnnnn
Hydraulic unit Harness Control unit
ABS-15

juuuiruL

Hydraulic unit Harness Control unit ABS-16

j JinjiruifL.
Control unit
ABS-17

jiruinjiri—
JinjiruifL.
Control unit
ABS-18

j
No signal; failure condi-tions not stored
in
memory
Control unit Control unit connector (17-pin) Battery capacity Alternator output voltage Wiring harness (warning light-control unit-check connector)
Inspect, and repair or replace as necessary
j
No signal; failure condi-tions not stored
in
memory
No problem When warning light does
not
illuminate with engine running and
no
jumper wire

76G11X092
11-75