oil pressure NISSAN X-TRAIL 2003 Electronic Repair Manual

AT-4
Differential Side Oil Seal Replacement .................457
Revolution Sensor Replacement ..........................457
REMOVAL AND INSTALLATION ...........................458
Removal ...............................................................458
Installation .............................................................459
OVERHAUL .............................................................461
Components .........................................................461
Oil Channel ...........................................................464
Locations of Adjusting Shims, Needle Bearings,
Thrust Washers and Snap Rings ..........................465
DISASSEMBLY .......................................................466
Disassembly .........................................................466
REPAIR FOR COMPONENT PARTS ......................482
Manual Shaft ........................................................482
Oil Pump ...............................................................485
Control Valve Assembly ........................................489
Control Valve Upper Body ....................................498
Control Valve Lower Body ....................................502
Reverse Clutch .....................................................504
High Clutch ...........................................................507
Forward and Overrun Clutches ............................512
Low & Reverse Brake ...........................................518
Rear Internal Gear, Forward Clutch Hub and Over-
run Clutch Hub ......................................................521
Output Shaft, Idler Gear, Reduction Pinion Gear and
Bearing Retainer ...................................................525
Band Servo Piston Assembly ...............................530
Final Drive ............................................................535ASSEMBLY ............................................................. 540
Assembly (1) ......................................................... 540
Adjustment (1) ....................................................... 541
Assembly (2) ......................................................... 546
Adjustment (2) ....................................................... 553
Assembly (3) ......................................................... 556
SERVICE DATA AND SPECIFICATIONS (SDS) .... 563
General Specifications .......................................... 563
Shift Schedule ....................................................... 563
Stall Revolution ..................................................... 563
Line Pressure ........................................................ 563
Control Valves ....................................................... 564
Accumulator .......................................................... 564
Clutch and Brakes ................................................. 564
Final Drive ............................................................. 566
Planetary Carrier and Oil Pump ............................ 567
Input Shaft ............................................................. 568
Reduction Pinion Gear .......................................... 568
Band Servo ........................................................... 569
Output Shaft .......................................................... 569
Bearing Retainer ................................................... 569
Total End Play ....................................................... 569
Reverse Clutch End Play ...................................... 570
Removal and Installation ....................................... 570
Shift Solenoid Valves ............................................ 570
Solenoid Valves .................................................... 570
A/T Fluid Temperature Sensor .............................. 570
Revolution Sensor ................................................. 571
Dropping Resistor ................................................. 571

PREPARATION
AT-9
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PREPARATIONPFP:00100
Special Service ToolsECS004Q5
Tool number
To o l n a m eDescription
KV381054S0 Puller
lRemoving differential side oil seals
lRemoving differential side bearing outer race
lRemoving idler gear bearing outer race
a: 250 mm (9.84 in)
b: 160 mm (6.30 in)
ST33400001 Drift
lInstalling differential side oil seal
F04B
lInstalling oil seal on oil pump housing
a: 60 mm (2.36 in) dia.
b: 47 mm (1.85 in) dia.
ST2505S001 Oil
pressure gauge set 1
ST25051001 Oil
pressure gauge 2
ST25052000 Hose 3
ST25053000 Joint pipe
4 ST25054000 Adapter
5 ST25055000 Adapter
lMeasuring line pressure
ST27180001 Puller
lRemoving idler gear
a: 100 mm (3.94 in)
b: 110 mm (4.33 in)
c: M8 x 1.25P
ST23540000 Pin punch
lRemoving and installing parking rod plate and
manual plate pins
a: 2.3 mm (0.091 in) dia.
b: 4 mm (0.16 in) dia.
ST25710000 Pin punch
lAligning groove of manual shaft and hole of
transmission case
a: 2 mm (0.08 in) dia.
NT414
NT086
NT097
NT424
NT442
NT410

AT-20
OVERALL SYSTEM
l*1: Operates when overdrive control switch is set in “OFF” position.
l*2: Oil pressure is applied to both 2nd “apply” side and 3rd “release” side of band servo piston. However, brake band does not con-
tract because oil pressure area on the “release” side is greater than that on the “apply” side.
l*3: Oil pressure is applied to 4th “apply” side in condition *2 above, and brake band contracts.
l*4: A/T will not shift to 4th when overdrive control switch is set in “OFF” position.
l*5: Operates when overdrive control switch is “OFF”.
l:Operates.
lA: Operates when throttle opening is less than 3/16, activating engine brake.
lB: Operates during “progressive” acceleration.
lC: Operates but does not affect power transmission.
lD: Operates when throttle opening is less than 3/16, but does not affect engine brake.
POWER TRANSMISSION
“N” and “P” Positions
l“N” position
Power from the input shaft is not transmitted to the output shaft because the clutches do not operate.
l“P” position
NNEUTRAL
POSITION
D*41st *1D B B
Automatic
shift
1Û2Û3Û
4 2nd *1A B
3rd *1A *2C C B
*5
4th C *3C C
21st D B BAutomatic
shift
1Û2 2nd A B
11stBLocks (held
stationary) in
1st speed
1Ü2 2ndB Shift positionRever
se
clutch
5High
clutch
6For-
ward
clutch
15Over-
run
clutch
17Band servo
Forward
one-way
clutch
16Low
one-
way
clutch
18Low &
revers
e
brake
19Lock-
upRemarks
2nd
apply3rd
releas
e4th
apply

OVERALL SYSTEM
AT-31
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Control of Shift Valves A and B
Pilot pressure generated by the operation of shift solenoid valves A and B is applied to the end face of shift
valves A and B.
The drawing above shows the operation of shift valve B. When the shift solenoid valve is “ON”, pilot pressure
applied to the end face of the shift valve overcomes spring force, moving the valve upward.
LOCK-UP CONTROL
The torque converter clutch piston in the torque converter is locked to eliminate torque converter slip to
increase power transmission efficiency. The solenoid valve is controlled by an ON-OFF duty signal sent from
the TCM. The signal is converted to an oil pressure signal which controls the torque converter clutch piston.
Conditions for Lock-up Operation
When vehicle is driven in 4th gear position, vehicle speed and throttle opening are detected. If the detected
values fall within the lock-up zone memorized in the TCM, lock-up is performed.
Torque Converter Clutch Solenoid Valve Control
The torque converter clutch solenoid valve is controlled by the TCM.
The plunger closes the drain circuit during the “OFF” period, and
opens the circuit during the “ON” period. If the percentage of OFF-
time increases in one cycle, the pilot pressure drain time is reduced
and pilot pressure remains high.
SAT009J
Overdrive control switch ON OFF
Selector lever “D” position
Gear position D
4D3
Vehicle speed sensor More than set value
Throttle position sensor Less than set opening
Closed throttle position switch OFF
A/T fluid temperature sensor More than 40°C(104°F)
SAT010J

OVERALL SYSTEM
AT-33
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Overrun Clutch Solenoid Valve Control
TheoverrunclutchsolenoidvalveisoperatedbyanON-OFFsignal
transmitted by the TCM to provide overrun clutch control (engine
brake control).
When this solenoid valve is “ON”, the pilot pressure drain port
closes. When it is “OFF”, the drain port opens.
During the solenoid valve “ON” pilot pressure is applied to the end
face of the overrun clutch control valve.
Overrun Clutch Control Valve Operation
When the solenoid valve is “ON”, pilot pressure is applied to the
overrun clutch control valve. This pushes up the overrun clutch con-
trol valve. The line pressure is then shut off so that the clutch does
not engage.
When the solenoid valve is “OFF”, pilot pressure is not generated. At
this point, the overrun clutch control valve moves downward by
spring force. As a result, overrun clutch operation pressure is pro-
vided by the overrun clutch reducing valve. This causes the overrun
clutch to engage.
In the 1 position, the overrun clutch control valve remains pushed
down so that the overrun clutch is engaged at all times.
Control ValveECS004QG
FUNCTION OF CONTROL VALVES
SAT015J
SAT016J
Valve name Function
Pressure regulator valve, plug
and sleeveRegulates oil discharged from the oil pump to provide optimum line pressure for all driving condi-
tions.
Pressure modifier valve and
sleeveUsed as a signal supplementary valve to the pressure regulator valve. Regulates pressure-modi-
fier pressure (signal pressure) which controls optimum line pressure for all driving conditions.
Pilot valve Regulates line pressure to maintain a constant pilot pressure level which controls lock-up mecha-
nism, overrun clutch, shift timing.
Accumulator control valve Regulates accumulator back-pressure to pressure suited to driving conditions.
Manual valve Directs line pressure to oil circuits corresponding to select positions.
Hydraulic pressure drains when the shift lever is in Neutral.
Shift valve A Simultaneously switches four oil circuits using output pressure of shift solenoid valve A to meet
driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and up-shifting (1st®2nd®3rd®4th gears/4th®3rd®2nd
®1st gears) in combination with shift valve B.
Shift valve B Simultaneously switches three oil circuits using output pressure of shift solenoid valve B in rela-
tion to driving conditions (vehicle speed, throttle opening, etc.).
Provides automatic downshifting and up-shifting (1st®2nd®3rd®4th gears/4th®3rd®2nd
®1st gears) in combination with shift valve A.

AT-34
OVERALL SYSTEM
Overrun clutch control valve Switches hydraulic circuits to prevent engagement of the overrun clutch simultaneously with appli-
cation of the brake band in D
4. (Interlocking occurs if the overrun clutch engages during D4.)
1st reducing valve Reduces low & reverse brake pressure to dampen engine-brake shock when down-shifting from
the “1” position 1
2to 11.
Overrun clutch reducing valve Reduces oil pressure directed to the overrun clutch and prevents engine-brake shock.
In “1” and “2” positions, line pressure acts on the overrun clutch reducing valve to increase the
pressure-regulating point, with resultant engine brake capability.
Torque converter relief valve Prevents an excessive rise in torque converter pressure.
Torque converter clutch control
valve, plug and sleeveActivates or inactivates the lock-up function.
Also provides smooth lock-up through transient application and release of the lock-up system.
1-2 accumulator valve and piston Dampens the shock encountered when 2nd gear band servo contracts, and provides smooth
shifting.
3-2 timing valve Switches oil pressure with 3-2 timing valve according to throttle opening.
Shuttle control valve Reduces shock when down-shifting from 3rd to 2nd and regulates overrun clutch.
Cooler check valve Regulates oil pressure which causes lock-up when driving at low speeds.Valve name Function

AT-68
[EURO-OBD]
TROUBLE DIAGNOSIS — BASIC INSPECTION
Line Pressure Test
ECS004QS
LINE PRESSURE TEST PORTS
Location of line pressure test ports are shown in the illustration.
lAlways replace pressure plugs as they are self-sealing
bolts.
LINE PRESSURE TEST PROCEDURE
1. Check A/T fluid and engine oil levels. If necessary, add fluid or
oil.
2. Drive vehicle for approx. 10 minutes or until engine oil and ATF
reach operating temperature.
3. Install pressure gauge to corresponding line pressure port.
4. Set parking brake and block wheels.
lContinue to depress brake pedal fully while line pressure
test is being performed at stall speed.
SCIA0709E
ATF operating temperature: 50 - 80°C (122 -176°F)
SAT647B
UAT008
UAT008

TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-69
[EURO-OBD]
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5. Start engine and measure line pressure at idle and stall speed.
lWhen measuring line pressure at stall speed, follow the
stall test procedure.
Line pressure: Refer toAT-563, "
SERVICE DATA AND SPECIFI-
CATIONS (SDS)".
JUDGEMENT OF LINE PRESSURE TEST
Road TestECS004QT
DESCRIPTION
lThe purpose of the test is to determine overall performance of A/
T and analyze causes of problems.
lThe road test consists of the following three parts:
1. Check before engine is started
2. Check at idle
SAT493G
Judgement Suspected parts
At idleLine pressure is low in all positions.
lOil pump wear
lControl piston damage
lPressure regulator valve or plug sticking
lSpring for pressure regulator valve damaged
lFluid pressure leakage between oil strainer and pressure regulator valve
lClogged strainer
Line pressure is low in particular posi-
tion.
lFluid pressure leakage between manual valve and particular clutch
lFor example, line pressure is:
-Low in “R” and “1” positions, but
-Normal in “D” and “2” positions.
Therefore, fluid leakage exists at or around low and reverse brake circuit.
Refer to “CLUTCH AND BAND CHART”,AT-19, "
CLUTCH AND BAND
CHART".
Line pressure is high.
lMaladjustment of throttle position sensor
lA/T fluid temperature sensor damaged
lLine pressure solenoid valve sticking
lShort circuit of line pressure solenoid valve circuit
lPressure modifier valve sticking
lPressure regulator valve or plug sticking
lOpen in dropping resistor circuit
At stall
speedLine pressure is low.
lMaladjustment of throttle position sensor
lLine pressure solenoid valve sticking
lShort circuit of line pressure solenoid valve circuit
lPressure regulator valve or plug sticking
lPressure modifier valve sticking
lPilot valve sticking
SAT786A

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
AT-87
[EURO-OBD]
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Transaxle noise in “P” and “N” posi-
tions.ON vehicle1. Fluid levelAT-64,
"FLUID
LEVEL
CHECK"
¬
2. Line pressure testAT-68, "
Line
Pressure
Te s t"
¬
3. Throttle position sensor (Accelerator
pedal position (App) sensor) AjustmentEC-154, "
DTC P0121 APP
SENSOR"
4. Vehicle speed sensor·A/T (Revolution
sensor) and vehicle speed sensor·MTRAT-392,
"VEHICLE
SPEED
SENSOR·A/
T(REVO-
LUTION
SENSOR)",
AT-397,
"DTC VEHI-
CLE
SPEED
SENSOR
MTR"
AT-142,
"DTC P0720
VEHICLE
SPEED
SENSOR·A/
T(REVO-
LUTION
SENSOR)",
AT-222,
"DTC VEHI-
CLE SPEED
SENSOR
MTR"
5. Engine speed signalAT-432,"ENGINE
SPEED
SIGNAL"
AT-147,
"DTC P0725
ENGINE
SPEED
SIGNAL"
OFF vehicle6. Oil pumpAT-485, "
Oil
Pump"¬
7. Torque converterAT-465,
"Locations
of Adjusting
Shims, Nee-
dle Bear-
ings, Thrust
Washers
and Snap
Rings"
¬
Vehicle moves when changing into
“P” position, or parking gear does
not disengage when shifted out of
“P” position.
AT- 2 3 4 , "
3. In“P”Position, Vehicle
Moves Forward Or Backward When
Pushed"
ON vehicle 1. Control cable adjustmentAT-456,"Control
Cable
Adjustment"
¬
OFF vehicle 2. Parking componentsAT-461,
"Compo-
nents",AT-
482,
"REPAIR
FOR COM-
PONENT
PA R T S"
¬ Symptom Condition Diagnostic ItemReference Page
Except for
Euro-OBDEURO-OBD

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
AT-93
[EURO-OBD]
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Clutches or brakes slip somewhat in
starting.ON vehicle1. Fluid levelAT-64,
"FLUID
LEVEL
CHECK"
¬
2. Control cable adjustmentAT-456,
"Control
Cable
Adjustment"
¬
3. Throttle position sensor (Accelerator
pedal position (App) sensor) AdjustmentEC-154, "
DTC P0121 APP
SENSOR"
4. Line pressure testAT-68, "
Line
Pressure
Te s t"
¬
5. Line pressure solenoid valveAT-436,
"LINE
PRES-
SURE
SOLENOID
VA LV E"
AT-186,
"DTC P0745
LINE PRES-
SURE
SOLENOID
VA LV E"
6. Control valve assemblyAT-454,
"Control
Va lv e
Assembly
and Accu-
mulators"
¬
7. Accumulator N-DAT-454,
"Control
Va lv e
Assembly
and Accu-
mulators"
¬
OFF vehicle8. Forward clutchAT-512,
"Forward
and Overrun
Clutches"
¬
9. Reverse clutchAT-504,
"Reverse
Clutch"
¬
10. Low & reverse brakeAT-518,
"Low&
Reverse
Brake"
¬
11. Oil pumpAT-485, "
Oil
Pump"¬
12. Torque converterAT-465,
"Locations
of Adjusting
Shims, Nee-
dle Bear-
ings, Thrust
Washers
and Snap
Rings"
¬ Symptom Condition Diagnostic ItemReference Page
Except for
Euro-OBDEURO-OBD