sensor MAZDA 626 1987 Workshop Manual

10 OUTLINE
86U10X-004
1. Steering wheel
2. Steering shaft
3. Intermediate shaft
4. Steering gear assembly
5. Pressure hose
6. Return hose
7. Oil pump
8. Solenoid valve
9. Control unit
10. Reserve tank
11. Steering angle sensor
12. Check connector
Note
Electronically - controlled power steering is abbreviated ECPS.
10—4

OUTLINE 10
86U10X-005
1. Reserve tank
2. Oil pump
3. Front steering gear assembly
4. Speed sensor
5. Control unit
6. Steering angle transfer shaft
7. Solenoid valves
8. Rear steering gear assembly
9. Steering wheel
10. Steering shaft
11. Relay and timer
Note
4-wheel steering is abbreviated 4WS.
10—5

4-WHEEL STEERING GEAR AND LINKAGE 1 0
4-WHEEL STEERING GEAR AND LINKAGE
STRUCTURAL VIEW
1. Reserve tank
2. Oil pump
3. Front steering gear assembly
4. Speed sensor
5. Control unit
6. Steering angle transfer shaft
7. Solenoid valve
8. Rear steering gear assembly
9. Steering wheel
10. Steering shaft
11. Relay and timer
86U10X-056
10—31

1 0 4-WHEEL STEERING GEAR AND LINKAGE
86U10X-085
Rear Steering Gear and Linkage
1. Check the following and replace the rear steering
gear assembly if necessary.
(a) Damaged or cracked case
(b) Faulty stepper motor or rear-to-front steering
ratio sensor
(c) Sticking bearings
(d) Oil leakage
Note
There is no fluid in a new replacement rear
steering gear assembly, add fluid to the spe-
cified level. (Refer to 10—12.)
2. Check and tighten bolts and nuts, if necessary.
3. Check the following and replace any faulty parts.
(a) Cracked, damaged, or deteriorated rear stee-
ring gear boots and bands
(b) Cracked or damaged oil pan
(c) Malfunctioning solenoid valve
86U10X-086
10-46

ELECTRICAL COMPONENTS OF ELECTRONICALLY-CONTROLLED POWER STEERING (ECPS) 1 0
Diagnosis Table
Condition Output pattern Malfunction Flow chart
No.
4.4V
0V-
10 seconds Power steering sole-noid valve or wiring harness (Control unit to Solenoid valve)
P/S—1
Refer to page
10-91
4.4V
0V-
Wiring harness (Con-
trol unit to Ignition coil) P/S—2 Refer to page 10-91
Steering wheel in straight-ahead po-sition with engine idling.
4.4V
OV-
Steering wheel angle sensor or wiring har-ness (Control unit to Angle sensor)
P/S—3 Refer to page 10-92
4.4V
ov-
Normal operation
Wiring harness (Fuse box to Control unit or Control unit to Body ground)
P/S—5 Refer to page 10—93
OV
10 seconds Power steering sole-
noid valve or wiring
harness (Control unit
to Solenoid valve)
P/S—1 Refer to page 10—91
B Steering wheel turned 45° left and right from center with engine idling
4.4V
0V
Wiring harness (Con-
trol unit to Ignition coil)
P/S—2 Refer to page 10-91
4.4V
0V'
Normal operation
4.4V
0V-
Steering wheel angle
sensor or wiring har-
ness (Control unit to
Angle sensor)
P/S—3 Refer to page 10—92
76G10X-023
10-89

1 0 ELECTRICAL COMPONENTS OF ELECTRONICALLY-CONTROLLED POWER STEERING (ECPS)
Condition Output pattern Malfunction Flow chart No.
B Cont'd
OV
Wiring harness (Fuse
box to Control unit or
Control unit to Body
ground)
P/S—5 Refer to page 10-93
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
4.4V —
1 3 s econds Power steering sole-noid valve or wiring harness (Control unit to Solenoid valve)
P/S—1 Refer to page 10-91
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
uv
Power steering sole-noid valve or wiring harness (Control unit to Solenoid valve)
P/S—1 Refer to page 10-91
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
4.4V
n\i
—
Wiring harness (Con-trol unit to Ignition coil) P/S—2 Refer to page 10-91
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
Wiring harness (Con-trol unit to Ignition coil) P/S—2 Refer to page 10-91
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
4.4V
Steering wheel angle sensor or wiring har-ness (Control unit to Angle sensor)
P/S-3 Refer to page 10—92
C
Front wheels driv-en at more than 10 km/h (6.2 mph)

V
Steering wheel angle sensor or wiring har-ness (Control unit to Angle sensor)
P/S-3 Refer to page 10—92
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
4.4V
Vehicle speed sensor or wiring harness
(Control unit to Meter)
P/S—4 Refer to page 10-92
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
uv
Vehicle speed sensor or wiring harness
(Control unit to Meter)
P/S—4 Refer to page 10-92
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
4.4V
OV —
Normal operation —
C
Front wheels driv-en at more than 10 km/h (6.2 mph)
OV
Wiring harness (Fuse box to Control unit or Control unit to Body ground)
P/S—5 Refer to page 10-93
76G10X-024
10-90

1 0 ELECTRICAL COMPONENTS OF ELECTRONICALLY-CONTROLLED POWER STEERING (ECPS)
OK
Check for continuity between each terminals of steer-ing angle sensor and control unit harness side con-nector.
Terminal Continuity Angle sensor Control unit Continuity
(G) KG) Yes
(GY) H(GY) Yes
(GW) J(GW) Yes
Repair wiring harness (Control unit to angle sensor).
OK
Replace control unit.
OK
Replace control unit.
76G10X-043
10—92

ELECTRICAL COMPONENTS OF ELECTRONICALLY-CONTROLLED POWER STEERING (ECPS) 1 0
Broken wiring harness (Fuse box
P/S—5 to Control unit, Control unit or to Body ground)
Measure voltage between terminal of control unit
connector and body ground with ignition ON.
Terminal Voltage UK Replace the control unit.
E(BG) Approx. 12V
D(B) Approx. OV
NG
Replace METER 10A fuse or repair wiring harnesses (Fuse box to Control unit or Control unit to Body ground).
86U10X-218
86U10X-219
Power Steering Solenoid Valve
Inspection
1. Listen for actuation sound of the solenoid valve
when applying 12V between A and B terminals.
2. If no sound is heard, check the resistance of the
solenoid valve with an ohmmeter.
Terminals Resistance
A — B 3.4—6.9 Q
3.
If
there is no continuity, replace the solenoid valve.
Steering Angle Sensor
Inspection
Refer to page 15—16.
Vehicle Speed Sensor
Inspection
Refer to page 15—88.
76G10X-044
10-93

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