2001 NISSAN X-TRAIL oil pressure

AT-34
OVERALL SYSTEM
Control Valve
ECS004QG
FUNCTION OF CONTROL VALVES
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.
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
2 to 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.

TROUBLE DIAGNOSIS — BASIC INSPECTION
AT-67
[EURO-OBD]
D
E
F
G
H
I
J
K
L
MA
B
AT
Line Pressure TestECS004QS
LINE PRESSURE TEST PORTS
Location of line pressure test ports are shown in the illustration.
●Always 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 AT F
reach operating temperature.
3. Install pressure gauge to corresponding line pressure port.
4. Set parking brake and block wheels.
●Continue 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

AT-68
[EURO-OBD]
TROUBLE DIAGNOSIS — BASIC INSPECTION
5. Start engine and measure line pressure at idle and stall speed.
●When measuring line pressure at stall speed, follow the
stall test procedure.
Line pressure: Refer to AT- 5 2 1 , "
SERVICE DATA AND SPECIFI-
CATIONS (SDS)" .
JUDGEMENT OF LINE PRESSURE TEST
Road TestECS004QT
DESCRIPTION
●The purpose of the test is to determine overall performance of A/
T and analyze causes of problems.
●The 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.
●Oil pump wear
●Control piston damage
●Pressure regulator valve or plug sticking
●Spring for pressure regulator valve damaged
●Fluid pressure leakage between oil strainer and pressure regulator valve
●Clogged strainer
Line pressure is low in particular posi-
tion.
●Fluid pressure leakage between manual valve and particular clutch
●For 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 AT- 1 9 , "
CLUTCH AND BAND CHART" .
Line pressure is high.
●Maladjustment of throttle position sensor
●A/T fluid temperature sensor damaged
●Line pressure solenoid valve sticking
●Short circuit of line pressure solenoid valve circuit
●Pressure modifier valve sticking
●Pressure regulator valve or plug sticking
●Open in dropping resistor circuit
At stall
speedLine pressure is low.
●Maladjustment of throttle position sensor
●Line pressure solenoid valve sticking
●Short circuit of line pressure solenoid valve circuit
●Pressure regulator valve or plug sticking
●Pressure modifier valve sticking
●Pilot valve sticking
SAT786A

AT-86
[EURO-OBD]
TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
PFP:00000
Symptom ChartECS004QU
Numbers are arranged in order of inspection.
Perform inspections starting with number one and work up.
Symptom Condition Diagnostic ItemReference Page
EURO-OBD
Engine cannot start in “P” and “N”
positions.
AT- 2 11 , "
Engine Cannot Be Started
In “P” and “N” Position"
ON vehicle1. Ignition switch and starterPG-2, "
POWER SUPPLY
ROUTING",SC-20,
"STARTING SYSTEM"
2. Control cable adjustmentAT-416, "Control Cable
Adjustment"
3. PNP switchAT- 11 0 , "
DTC P0705
PARK/NEUTRAL POSI-
TION (PNP) SWITCH"
Engine starts in position other than
“N” and “P” positions.
AT- 2 11 , "
Engine Cannot Be Started
In “P” and “N” Position"
ON vehicle1. Control cable adjustmentAT-416, "
Control Cable
Adjustment"
2. PNP switchAT- 11 0 , "
DTC P0705
PARK/NEUTRAL POSI-
TION (PNP) SWITCH"
Transaxle noise in “P” and “N” posi-
tions.ON vehicle1. Fluid levelAT- 6 3 , "
FLUID LEVEL
CHECK"
2. Line pressure testAT- 6 7 , "Line Pressure Test"
3. Accelerator pedal position (APP) sensorAT-180, "
DTC P1705
ACCELERATOR PEDAL
POSITION (APP) SEN-
SOR"
4. Vehicle speed sensor·A/T (Revolution
sensor) and vehicle speed sensor·MTRAT-122, "
DTC P0720 VEHI-
CLE SPEED SENSOR·A/T
(REVOLUTION SEN-
SOR)",
AT-199, "
DTC VEHICLE
SPEED SENSOR MTR"
OFF vehicle5. Oil pumpAT-444, "
Oil Pump"
6. Torque converterAT-425, "
Locations of
Adjusting Shims, Needle
Bearings, 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 1 2 , "
In “P” Position, Vehicle
Moves Forward Or Backward When
Pushed"
ON vehicle 1. Control cable adjustmentAT-416, "Control Cable
Adjustment"
OFF vehicle 2. Parking componentsAT-421, "
Components",AT-
441, "REPAIR FOR COM-
PONENT PARTS"
Vehicle runs in “N” position.
AT- 2 1 3 , "
In “N” Position, Vehicle
Moves"
ON vehicle 1. Control cable adjustmentAT-416, "Control Cable
Adjustment"
OFF vehicle2. Forward clutchAT-471, "
Forward and
Overrun Clutches"
3. Reverse clutchAT-463, "Reverse Clutch"
4. Overrun clutchAT-471, "Forward and
Overrun Clutches"

TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
AT-89
[EURO-OBD]
D
E
F
G
H
I
J
K
L
MA
B
AT
Vehicle will not run in “D”, “1”, “2”
positions (but runs in “R” position).
Clutch slips. Very poor acceleration.
AT-218, "
Vehicle Does Not Creep
Forward In “D”,“2” Or “1” Position"
OFF vehicle7. Reverse clutchAT-463, "
Reverse Clutch"
8. High clutchAT-466, "High Clutch"
9. Forward clutchAT-471, "Forward and
Overrun Clutches"
10. Forward one-way clutchAT-421, "OVERHAUL"
11. Low one-way clutchAT-421, "
OVERHAUL",AT-
425, "Locations of Adjust-
ing Shims, Needle Bear-
ings, Thrust Washers and
Snap Rings"
Clutches or brakes slip somewhat in
starting.ON vehicle1. Fluid levelAT-63, "
FLUID LEVEL
CHECK"
2. Control cable adjustmentAT-416, "Control Cable
Adjustment"
3. Accelerator pedal position (APP) sensorAT-180, "
DTC P1705
ACCELERATOR PEDAL
POSITION (APP) SEN-
SOR"
4. Line pressure testAT-67, "Line Pressure Test"
5. Line pressure solenoid valveAT-163, "
DTC P0745 LINE
PRESSURE SOLENOID
VA LV E"
6. Control valve assemblyAT-414, "
Control Valve
Assembly and Accumula-
tors"
7. Accumulator N-DAT-414, "
Control Valve
Assembly and Accumula-
tors"
8. Shift solenoid valve AAT-170, "
DTC P0750
SHIFT SOLENOID VALVE
A"
9. Shift solenoid valve BAT-175, "
DTC P0755
SHIFT SOLENOID VALVE
B"
10. Overrun clutch solenoid valveAT-185, "
DTC P1760
OVERRUN CLUTCH
SOLENOID VALVE"
11. Torque converter clutch solenoid valveAT-158, "
DTC P0740
TORQUE CONVERTER
CLUTCH SOLENOID
VA LV E"
OFF vehicle12. Forward clutchAT-471, "
Forward and
Overrun Clutches"
13. Reverse clutchAT-463, "Reverse Clutch"
14. Low & reverse brakeAT-476, "Low & Reverse
Brake"
15. Oil pumpAT-444, "Oil Pump"
16. Torque converterAT-425, "
Locations of
Adjusting Shims, Needle
Bearings, Thrust Washers
and Snap Rings"
Symptom Condition Diagnostic ItemReference Page
EURO-OBD

AT-90
[EURO-OBD]
TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
Excessive creep. ON vehicle 1. Engine idling rpmEC-38
[QR25 (WITH
EURO-OBD)], EC-448
[QR25 (WITHOUT EURO-
OBD)], EC-771
[QR20
(WITH EURO-OBD)], EC-
1135 [QR20 (WITHOUT
EURO-OBD)]
No creep at all.
AT- 2 1 5 , "
Vehicle Does Not Creep
Backward In “R” Position" and AT-
218, "Vehicle Does Not Creep For-
ward In “D”,“2” Or “1” Position"
ON vehicle1. Fluid levelAT- 6 3 , "
FLUID LEVEL
CHECK"
2. Line pressure testAT-396, "LINE PRES-
SURE SOLENOID VALVE"
3. Control valve assemblyAT-414, "
Control Valve
Assembly and Accumula-
tors"
OFF vehicle4. Forward clutchAT-471, "
Forward and
Overrun Clutches"
5. Oil pumpAT-444, "Oil Pump"
6. Torque converterAT-425, "
Locations of
Adjusting Shims, Needle
Bearings, Thrust Washers
and Snap Rings"
Failure to change gear from “D1 ” to
“D
2 ”.ON vehicle1. Control cable adjustmentAT-416, "
Control Cable
Adjustment"
2. Shift solenoid valve AAT-170, "
DTC P0750
SHIFT SOLENOID VALVE
A"
3. Control valve assemblyAT-414, "
Control Valve
Assembly and Accumula-
tors"
4. Vehicle speed sensor·A/T (Revolution
sensor) and vehicle speed sensor·MTRAT-122, "
DTC P0720 VEHI-
CLE SPEED SENSOR·A/T
(REVOLUTION SEN-
SOR)",AT- 1 9 9 , "DTC
VEHICLE SPEED SEN-
SOR MTR"
5. Accelerator pedal position (APP) sensorAT-180, "
DTC P1705
ACCELERATOR PEDAL
POSITION (APP) SEN-
SOR"
OFF vehicle 6. Brake bandAT-488, "Band Servo Pis-
ton Assembly"
Symptom Condition Diagnostic ItemReference Page
EURO-OBD

AT-100
[EURO-OBD]
TROUBLE DIAGNOSIS — GENERAL DESCRIPTION
Races extremely fast or slips in
changing from “D
4 ” or “D3 ” to “D1 ”
when depressing pedal.ON vehicle1. Fluid levelAT- 6 3 , "
FLUID LEVEL
CHECK"
2. Accelerator pedal position (APP) sensorAT-180, "
DTC P1705
ACCELERATOR PEDAL
POSITION (APP) SEN-
SOR"
3. Line pressure testAT- 6 7 , "Line Pressure Test"
4. Line pressure solenoid valveAT-163, "
DTC P0745 LINE
PRESSURE SOLENOID
VA LV E"
5. Shift solenoid valve AAT-170, "
DTC P0750
SHIFT SOLENOID VALVE
A"
6. Shift solenoid valve BAT-175, "
DTC P0755
SHIFT SOLENOID VALVE
B"
7. Control valve assemblyAT-414, "
Control Valve
Assembly and Accumula-
tors"
OFF vehicle8. Forward clutchAT-471, "
Forward and
Overrun Clutches"
9. Forward one-way clutchAT-421, "OVERHAUL"
10. Low one-way clutchAT-421, "
OVERHAUL",AT-
425, "Locations of Adjust-
ing Shims, Needle Bear-
ings, Thrust Washers and
Snap Rings"
Vehicle will not run in any position.ON vehicle1. Fluid levelAT- 6 3 , "
FLUID LEVEL
CHECK"
2. Control cable adjustmentAT-416, "Control Cable
Adjustment"
3. Line pressure testAT- 6 7 , "Line Pressure Test"
4. Line pressure solenoid valveAT-163, "
DTC P0745 LINE
PRESSURE SOLENOID
VA LV E"
OFF vehicle5. Oil pumpAT-444, "
Oil Pump"
6. Torque converterAT-425, "
Locations of
Adjusting Shims, Needle
Bearings, Thrust Washers
and Snap Rings"
7. Parking componentsAT-421, "Components"
Transmission noise in “D”, “2”, “1”
and “R” positions.ON vehicle 1. Fluid levelAT- 6 3 , "
FLUID LEVEL
CHECK"
OFF vehicle 2. Torque converterAT-425, "
Locations of
Adjusting Shims, Needle
Bearings, Thrust Washers
and Snap Rings"
Symptom Condition Diagnostic ItemReference Page
EURO-OBD

DTC P0734 A/T 4TH GEAR FUNCTION
AT-149
[EURO-OBD]
D
E
F
G
H
I
J
K
L
MA
B
AT
DTC P0734 A/T 4TH GEAR FUNCTIONPFP:31940
DescriptionECS004RM
●This malfunction will not be detected while the O/D OFF indicator lamp is indicating another self-diagnosis
malfunction.
●This malfunction is detected when the A/T does not shift into fourth gear position or line pressure is low as
instructed by the TCM. This is not caused by electrical malfunction (circuits open or shorted) but by
mechanical malfunction such as control valve sticking, improper solenoid valve operation, malfunctioning
oil pump or torque converter clutch, etc.
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Remarks: Specification data are reference values.
TCM TERMINALS AND REFERENCE VALUE
Remarks: Specification data are reference values.Gear position 1 2 3 4
Shift solenoid valve A ON (Closed) OFF (Open) OFF (Open) ON (Closed)
Shift solenoid valve B ON (Closed) ON (Closed) OFF (Open) OFF (Open)
Monitor item Condition Specification
Line pressure solenoid valve dutySmall throttle opening
(Low line pressure)
↓
Large throttle opening
(High line pressure)Approximately 24%
↓
Approximately 95%
Te r m i -
nal No.Wire color Item ConditionJudgement stan-
dard
(Approx.)
1R/WLine pressure
solenoid valveWhen releasing accelerator pedal
after warming up engine.1.5 - 3.0V
When depressing accelerator pedal
fully after warming up engine.0V
2P/BLine pressure
solenoid valve
(with dropping
resistor)When releasing accelerator pedal
after warming up engine.5 - 14V
When depressing accelerator pedal
fully after warming up engine.0V
11 L / WShift solenoid
valve AWhen shift solenoid valve A oper-
ates.
(When driving in “D
1 ” or “D4 ”.)Battery voltage
When shift solenoid valve A does not
operate.
(When driving in “D
2 ” or “D3 ”.)0V
12 L/YShift solenoid
valve BWhen shift solenoid valve B oper-
ates.
(When driving in “D
1 ” or “D2 ”.)Battery voltage
When shift solenoid valve B does not
operate.
(When driving in “D
3 ” or “D4 ”.)0V