steering NISSAN TEANA 2008 Service Manual

ST-34
< ON-VEHICLE REPAIR >
HYDRAULIC LINE
HYDRAULIC LINE
Exploded ViewINFOID:0000000003806330
VQ25DE Models
JSGIA0401GB
1. Reservoir tank bracket 2. Bushing 3. Reservoir tank
4. Suction hose 5. Clamp 6. Copper washer
7. High pressure piping 8. Steering gear assembly 9. O-ring
10. Eye bolt 11. Pressure sensor
A. To power steering oil pump suction
hose.B. To power steering oil pump.
: Vehicle front
Refer to GI-4, "
Components" for symbols not described on the above.

HYDRAULIC LINE
ST-35
< ON-VEHICLE REPAIR >
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VQ35DE Models
Removal and InstallationINFOID:0000000003806331
CAUTION:
 Never apply fluid to the hose (1) and tube (2).
 Insert hose securely until it contacts spool (A) of tube.
 Leave clearance (L) when installing clamp (3).
JSGIA0402GB
1. Reservoir tank bracket 2. Bushing 3. Reservoir tank
4. Suction hose 5. Clamp 6. Copper washer
7. High pressure piping 8. Steering gear assembly 9. O-ring
10. Eye bolt 11. Pressure sensor
A. To power steering oil pump suction
hose.B. To power steering oil pump.
: Vehicle front
Refer to GI-4, "
Components" for symbols not described on the above.
Standard
L : 3 – 8 mm (0.12 – 0.31 in)
JSGIA0118ZZ

SERVICE DATA AND SPECIFICATIONS (SDS)
ST-37
< SERVICE DATA AND SPECIFICATIONS (SDS)
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SERVICE DATA AND SPECIFICATIONS (SDS)
SERVICE DATA AND SPECIFICATIONS (SDS)
General SpecificationsINFOID:0000000003806332
Steering Wheel Axial End Play and PlayINFOID:0000000003806333
Unit: mm (in)
Steering Wheel Turning ForceINFOID:0000000003806334
Unit: N·m (kg-m, in-lb)
Steering AngleINFOID:0000000003806335
Unit: Degree minute (Decimal degree)
Steering Column LengthINFOID:0000000003826226
Unit: mm (in)
Steering Column Mounting DimensionsINFOID:0000000003826227
Unit: mm (in)
Steering Column Operating RangeINFOID:0000000003806336
Steering gear modelPR26AF
Fluid capacity (Approx.)
(lmp qt)1.0 (7/8)
Item Standard
Steering wheel axial end play 0 (0)
Steering wheel play on the outer circumference 0 – 35 (0 – 1.38)
Item Standard
Steering wheel turning force 7.45 (0.76, 66)
ItemStandard
Tire size: 205/65R16 Tire size: 215/55R17
Inner wheelMinimum 38°00′ (38.0°)34°00′ (34.0°)
Nominal 41°00′ (41.0°)37°00′ (37.0°)
Maximum 42°30′ (42.5°)38°30′ (38.5°)
Outer wheel Nominal 33°00′ (31.0°)31°00′ (31.0°)
Item Standard
Column length484 – 486 (19.06 – 19.13)
Item Standard
Mounting dimension 19.5 (0.768) or less
Item Standard
Tilt operating range 37 mm (1.46 in)
Rotating torque 0.49 N·m (0.05 kg-m, 4 in-lb)

STC-1
STEERING
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SECTION STC
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CONTENTS
STEERING CONTROL SYSTEM
BASIC INSPECTION ....... .............................2
DIAGNOSIS AND REPAIR WORK FLOW .... .....2
Work Flow ........................................................... ......2
FUNCTION DIAGNOSIS ...............................3
EPS SYSTEM ... .............................................. .....3
System Diagram .................................................. ......3
System Description ...................................................3
Component Parts Location ........................................5
Component Description .............................................5
COMPONENT DIAGNOSIS ..........................6
POWER SUPPLY AND GROUND CIRCUIT .. .....6
Description .......................................................... ......6
Diagnosis Procedure .................................................6
POWER STEERING SOLENOID VALVE ...........7
Description .......................................................... ......7
Diagnosis Procedure .................................................7
Component Inspection ..............................................8
ENGINE SPEED SIGNAL CIRCUIT ............... .....9
Description .......................................................... ......9
Diagnosis Procedure .................................................9
VEHICLE SPEED SIGNAL CIRCUIT .................11
Description .......................................................... ....11
Diagnosis Procedure ...............................................11
ECU DIAGNOSIS .........................................13
POWER STEERING CONTROL UNIT ..............13
Reference Value .................................................. ....13
Wiring Diagram - ELECTRONICALLY CON-
TROLLED POWER STEERING SYSTEM - ............
14
Fail-Safe .............................................................. ....15
SYMPTOM DIAGNOSIS ..............................17
UNBALANCE STEERING WHEEL TURNING
FORCE (TORQUE VARIATION) .......................
17
Description ........................................................... ....17
Diagnosis Procedure ...............................................17
PRECAUTION ..............................................18
PRECAUTIONS .................................................18
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ............................................................. ....
18
Precaution Necessary for Steering Wheel Rota-
tion after Battery Disconnect ...................................
18
ON-VEHICLE REPAIR .................................19
POWER STEERING CONTROL UNIT ..............19
Exploded View ..................................................... ....19
Removal and Installation .........................................19

STC-2
< BASIC INSPECTION >
DIAGNOSIS AND REPAIR WORK FLOW
BASIC INSPECTION
DIAGNOSIS AND REPAIR WORK FLOW
Work FlowINFOID:0000000003893521
DETAILED FLOW
1.COLLECT THE INFORMATION FROM THE CUSTOMER
It is also important to clarify customer complaints before inspection. First of all, reproduce symptoms and
understand them fully. Ask customer about his/her complaints carefully. In some cases, it is necessary to
check symptoms by driving vehicle with customer.
CAUTION:
Customers are not professional. It is dangerous to make an easy guess like “maybe the customer
means that...,” or “maybe the customer mentions this symptom”.
>> GO TO 2.
2.CHECK THE STATUS
1. Check the power steering fluid leakage and power steering fluid level. Refer to ST-7, "
Inspection".
2. Check the drive belt tension. Refer to EM-12, "
Checking".
3. Check the power steering gear for damages, cracks and fluid leakage. Refer to ST-26, "
Inspection".
4. Check the relief oil pressure. Refer to ST-32, "
Inspection".
>> GO TO 3.
3.DIAGNOSIS CHART BY SYMPTOM
Perform the diagnosis by symptom. Refer to STC-17, "
Diagnosis Procedure".
>> GO TO 4.
4.FINAL CHECK
Check the input/output standard values for the power steering control unit.
Are the power steering control unit input/output values within standard ranges respectively?
YES >> INSPECTION END
NO >> GO TO 2.

EPS SYSTEM
STC-3
< FUNCTION DIAGNOSIS >
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FUNCTION DIAGNOSIS
EPS SYSTEM
System DiagramINFOID:0000000003893522
CONTROL DIAGRAM
CROSS-SECTIONAL VIEW
System DescriptionINFOID:0000000003893523
• The EPS system controls the power steering solenoid valve through the power steering control unit.
JSGIA0119GB
1. Combination meter 2. Power steering control unit 3. Power steering solenoid valve
4. Steering gear assembly 5. Gear housing assembly 6. Gear sub-assembly
7. Pinion 8. Power steering oil pump 9. Reservoir tank
JSGIA0376ZZ

STC-4
< FUNCTION DIAGNOSIS >
EPS SYSTEM
 The valve driving voltage to control the power steering solenoid
valve varies according to the vehicle speed.
OPERATION PRINCIPLE
During Parking (When Turning The Steering Wheel To The Right.)
1. Power steering solenoid valve is closed while a vehicle is stopped.
2. Pinion “1R”, “2R” and “3R” are closed depending on steering torque of steering wheel.
3. Oil pressure “P” in the gear housing assembly is the sum of oil pressures occurred in “2R” and “3R”. This
results in a light steering force because of high pressure.
During High-speed Operation
1. Power steering solenoid valve is opened during high-speed operation.
2. Pinion “1R”, “2R” and “3R” are closed depending on steering torque of steering wheel.
3. Oil pressure “2R” does not occur because the power steering solenoid valve is on full throttle.
4. Oil pressure “P” in the gear housing assembly includes only oil pressure occurred in “3R” and results in a
heavy steering force.
JSGIA0374GB
JSGIA0020GB
JSGIA0021GB

EPS SYSTEM
STC-5
< FUNCTION DIAGNOSIS >
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Component Parts LocationINFOID:0000000003893524
Component DescriptionINFOID:0000000003893525
1. Power steering solenoid valve 2. Power steering control unit
A. Steering gear assembly B. Glove box assembly removed
: Vehicle front
JSGIA0406ZZ
Component parts Reference/Function
Power steering control unit Signals from various sensors control the driving voltage to the power steering solenoid valve.
 The power steering control unit controls the driving voltage to the power steering solenoid valve
for maintaining the power steering assist force when the fail-safe function is activated. (The en-
gine speed signals control EPS system if any vehicle speed signal error is detected.)
Combination meterSTC-11, "
Description"
ECMSTC-9, "Description"
Power steering solenoid valveSTC-7, "Description"

STC-6
< COMPONENT DIAGNOSIS >
POWER SUPPLY AND GROUND CIRCUIT
COMPONENT DIAGNOSIS
POWER SUPPLY AND GROUND CIRCUIT
DescriptionINFOID:0000000003893526
Power supply to EPS system
Diagnosis ProcedureINFOID:0000000003893527
1.CHECK POWER SUPPLY
1. Turn the ignition switch OFF.
2. Disconnect power steering control unit harness connector.
3. Check voltage between power steering control unit harness connector and ground.
4. Turn the ignition switch ON.
CAUTION:
Never start the engine.
5. Check voltage between power steering control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> Check the following. If any items are damaged, repair or replace damaged parts.
 10A fuses (#3) open
- Harness for short or open between ignition switch and power steering control unit harness con-
nector No. 3 terminal.
- Ignition switch. Refer to PCS-64, "
Component Inspection".
2.CHECK GROUND CIRCUIT
1. Turn the ignition switch OFF.
2. Check continuity between power steering control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair open circuit or short to power in harness or connectors.
3.CHECK TERMINALS AND HARNESS CONNECTORS
Check power steering control unit pin terminals for damage or loose connection with harness connector.
Is the inspection result normal?
YES >> INSPECTION END
NO >> Repair or replace damaged parts.
Power steering control unit
—Voltage
Connector Terminal
M61 3 Ground 0 V
Power steering control unit
— Voltage
Connector Terminal
M61 3 Ground Battery voltage
Power steering control unit
—Continuity
Connector Terminal
M61 6 Ground Existed

POWER STEERING SOLENOID VALVE
STC-7
< COMPONENT DIAGNOSIS >
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POWER STEERING SOLENOID VALVE
DescriptionINFOID:0000000003893528
Power steering solenoid valve controls the power steering oil pressure in the gear housing assembly.
Diagnosis ProcedureINFOID:0000000003893529
1.CHECK POWER STEERING SOLENOID VALVE SIGNAL
1. Turn the ignition switch OFF.
2. Check voltage between power steering control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 4.
2.CHECK HARNESS BETWEEN POWER STEERING SOLENOID VALVE AND POWER STEERING CON-
TROL UNIT
1. Turn the ignition switch OFF.
2. Disconnect power steering solenoid valve harness connector.
3. Disconnect power steering control unit harness connector.
4. Check the continuity between power steering solenoid valve harness connector and the power steering
control unit harness connector.
5. Check continuity between power steering control unit harness connector and ground.
Is the inspection result normal?
YES >> GO TO 3.
NO >> Repair or replace damaged parts.
3.CHECK POWER STEERING SOLENOID VALVE
Check power steering solenoid valve. Refer to STC-8, "
Component Inspection".
Is the inspection result normal?
YES >> GO TO 4.
NO >> Replace gear-sub assembly. Refer to ST-18, "
Exploded View".
4.CHECK TERMINALS AND HARNESS CONNECTORS
 Check power steering control unit pin terminals for damage or loose connection with harness connector.
 Check power steering solenoid valve pin terminals for damage or loose connection with harness connector.
Is the inspection result normal?
Power steering control unit
— Condition Voltage (Approx.)
Connector Terminal
M61 1 GroundVehicle speed: 0 km/h (0 MPH)
(Engine is running)4.4 – 6.6 V
Vehicle speed: 100 km/h (62 MPH) 2.4 – 3.6 V
Power steering solenoid valve Power steering control unit
Continuity
Connector Terminal Connector Terminal
E52 1 M61 1 Existed
E52 2 M61 5 Existed
Power steering control unit
—Continuity
Connector Terminal
M61 1
Ground Not existed
M61 5