2006 NISSAN VERSA oil pressure

CVT-26
CVT SYSTEM
Revision: June 20062007 Versa
Line Pressure and Secondary Pressure ControlUCS005XW

When an input torque signal equivalent to the engine drive force is sent from the ECM to the TCM, the
TCM controls the line pressure solenoid valve and secondary pressure solenoid valve.

This line pressure solenoid controls the pressure regulator valve as the signal pressure and adjusts the
pressure of the operating oil discharged from the oil pump to the line pressure most appropriate to the
driving state. Secondary pressure is controlled by decreasing line pressure.
NORMAL CONTROL
Optimize the line pressure and secondary pressure, depending on driving conditions, on the basis of the throt-
tle position, the engine speed, the primary pulley (input) revolution speed, the secondary pulley (output) revo-
lution speed, the brake signal, the PNP switch signal, the lock-up signal, the voltage, the target gear ratio, the
fluid temperature, and the fluid pressure.
FEEDBACK CONTROL
When controlling the normal fluid pressure or the selected fluid pressure, the secondary pressure can be set
more accurately by using the fluid pressure sensor to detect the secondary pressure and controlling the feed-
back.
Shift ControlUCS005XX
In order to select the gear ratio which can obtain the driving force in accordance with driver's intention and the
vehicle condition, TCM monitors the driving conditions, such as the vehicle speed and the throttle position and
selects the optimum gear ratio, and determines the gear change steps to the gear ratio. Then send the com-
mand to the step motor, and control the flow-in/flow-out of line pressure from the primary pulley to determine
the position of the moving-pulley and control the gear ratio.
SCIA1846E
SCIA7958E

CVT SYSTEM
CVT-29
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CVT
Revision: June 20062007 Versa
Control ValveUCS005XZ
FUNCTION OF CONTROL VALVE
Name Function
Torque converter regulator valve Optimizes the supply pressure for the torque converter depending on driving conditions.
Pressure regulator valve Optimizes the discharge pressure from the oil pump depending on driving conditions.
TCC control valve

Activates or deactivate the lock-up.

Lock-up smoothly by opening lock-up operation excessively.
TCC solenoid valve Controls the TCC control valve or select control valve.
Shift control valveControls flow-in/out of line pressure from the primary pulley depending on the stroke dif-
ference between the stepping motor and the primary pulley.
Secondary valveControls the line pressure from the secondary pulley depending on operating condi-
tions.
Clutch regulator valve Adjusts the clutch operating pressure depending on operating conditions.
Secondary pressure solenoid valve Controls the secondary valve.
Line pressure solenoid valve Controls the line pressure control valve.
Step motor Controls the pulley ratio.
Manual valveTransmits the clutch operating pressure to each circuit in accordance with the selected
position.
Select control valve Engages forward clutch, reverse brake smoothly depending on select operation.
Select switch valveSwitches torque converter clutch solenoid valve control pressure use to torque con-
verter clutch control valve or select control valve.
Lock-up select solenoid valve Controls the select switch valve.

CVT-34
TROUBLE DIAGNOSIS
Revision: June 20062007 Versa
TROUBLE DIAGNOSISPFP:00004
DTC Inspection Priority ChartUCS005Y5
If some DTCs are displayed at the same time, perform inspections one by one based on the following priority
chart.
NOTE:
If DTC “U1000 CAN COMM CIRCUIT” is displayed with other DTCs, first perform the trouble diagnosis
for “DTC U1000 CAN COMMUNICATION LINE”. Refer to CVT-68
.
Fail-safeUCS005Y6
The TCM has an electrical fail-safe mode. This mode makes it possible to operate even if there is an error in a
main electronic control input/output signal circuit.
FAIL -S AFE F UN CTI ON
If any malfunction occurs in a sensor or solenoid, this function controls the CVT to make driving possible.
Output Speed Sensor (Secondary Speed Sensor)
The shift pattern is changed in accordance with throttle position when an unexpected signal is sent from the
output speed sensor (secondary speed sensor) to the TCM. The overdrive-off mode is inhibited, and the tran-
saxle is put in “D”.
Input Speed Sensor (Primary Speed Sensor)
The shift pattern is changed in accordance with throttle position and secondary speed (vehicle speed) when
an unexpected signal is sent from the input speed sensor (primary speed sensor) to the TCM. The sport mode
is inhibited, and the transaxle is put in “D”.
PNP Switch
If an unexpected signal is sent from the PNP switch to the TCM, the transaxle is put in “D”.
CVT Fluid Temperature Sensor
If an unexpected signal is sent from the CVT fluid temperature sensor to the TCM, the gear ratio in use before
receiving the unexpected signal is maintained or the gear ratio is controlled to keep engine speed under 3500
rpm.
Transmission Fluid Pressure Sensor A (Secondary Pressure Sensor)

If an unexpected signal is sent from the transmission fluid pressure sensor A (secondary pressure sensor)
to the TCM, the secondary pressure feedback control is stopped and the offset value obtained before the
non-standard condition occurs is used to control line pressure.

If transmission fluid pressure sensor A (secondary pressure sensor) error signal is input to TCM, second-
ary pressure feedback control stops, but line pressure is controlled normally.
Pressure Control Solenoid A (Line Pressure Solenoid)
If an unexpected signal is sent from the solenoid to the TCM, the pressure control solenoid A (line pressure
solenoid) is turned OFF to achieve the maximum fluid pressure.
Pressure Control Solenoid B (Secondary Pressure Solenoid)
If an unexpected signal is sent from the solenoid to the TCM, the pressure control solenoid B (secondary pres-
sure solenoid) is turned OFF to achieve the maximum fluid pressure.
Torque Converter Clutch Solenoid
If an unexpected signal is sent from the solenoid to the TCM, the torque converter clutch solenoid is turned
OFF to cancel the lock-up.
Step Motor
If an unexpected signal is sent from the step motor to the TCM, the step motor coil phases “A” through “D” are
all turned OFF to hold the gear ratio used right before the non-standard condition occurred.
Priority Detected items (DTC)
1 U1000 CAN communication line
2 Except above

TROUBLE DIAGNOSIS
CVT-45
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CVT
Revision: June 20062007 Versa
LINE PRESSURE TEST
Line Pressure Test Port
Line Pressure Test Procedure
1. Inspect the amount of engine oil and replenish if necessary.
2. Drive the car for about 10 minutes to warm it up so that the CVT fluid reaches in the range of 50 to 80°C
(122 to 176°F), then inspect the amount of CVT fluid and replenish if necessary.
NOTE:
The CVT fluid temperature rises in the range of 50 - 80°C (122 - 176°F) during 10 minutes of driving.
3. After warming up CVT, remove the oil pressure detection plug and install the oil pressure gauge [special
service tool: - (OTC3492)].
CAUTION:
When using the oil pressure gauge, be sure to use the O-ring attached to the oil pressure detec-
tion plug.
4. Securely engage the parking brake so that the tires do not turn.
5. Start the engine, and then measure the line pressure at both idle
and the stall speed.
CAUTION:

Keep the brake pedal pressed all the way down during
measurement.

When measuring the line pressure at the stall speed,
refer to CVT-43, "
STALL TEST" .
6. After the measurements are complete, install the oil pressure
detection plug and tighten to the specified torque below.
CAUTION:

Do not reuse O-ring.

Apply CVT fluid to O-ring.
SCIA6184E
SAT5 1 3G
: 7.5 N·m (0.77 kg-m, 66 in-lb)SAT4 9 3G

CVT-46
TROUBLE DIAGNOSIS
Revision: June 20062007 Versa
Line Pressure
*: Reference values
Judgement of Line Pressure Test
Road TestUCS005YC
DESCRIPTION

The purpose of the test is to determine overall performance of
CVT and analyze causes of problems.

The road test consists of the following three parts:
1. “Check Before Engine Is Started” CVT-49
.
2. “Check at Idle” CVT-49
.
3. “Cruise Test” CVT-50
.
Engine speed Line pressure kPa (kg/cm
2 , psi)
“R”, “D” and “L” positions
At idle 650 (6.63, 94.3)
At stall 4,250 (43.35, 616.3)*
Judgement Possible cause
Idle speedLow for all positions
(“P”, “R”, “N”, “D”, “L”)Possible causes include malfunctions in the pressure supply system and low oil pump output.
For example

Oil pump wear

Pressure regulator valve or plug sticking or spring fatigue

Oil strainer
oil pump
pressure regulator valve passage oil leak

Engine idle speed too low
Only low for a specific
positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.
HighPossible causes include a sensor malfunction or malfunction in the line pressure adjustment
function.
For example

Accelerator pedal position signal malfunction

CVT fluid temperature sensor malfunction

Pressure control solenoid A (line pressure solenoid) malfunction (sticking in OFF state, filter
clog, cut line)

Pressure regulator valve or plug sticking
Stall speedLine pressure does
not rise higher than
the line pressure for
idle.Possible causes include a sensor malfunction or malfunction in the pressure adjustment func-
tion.
For example

Accelerator pedal position signal malfunction

TCM malfunction

Pressure control solenoid A (line pressure solenoid) malfunction (shorting, sticking in ON
state)

Pressure regulator valve or plug sticking
The pressure rises,
but does not enter the
standard position.Possible causes include malfunctions in the pressure supply system and malfunction in the
pressure adjustment function.
For example

Accelerator pedal position signal malfunction

Pressure control solenoid A (line pressure solenoid) malfunction (sticking, filter clog)

Pressure regulator valve or plug sticking
Only low for a specific
positionPossible causes include an oil pressure leak in a passage or device related to the position after
the pressure is distributed by the manual valve.
SAT7 8 6A

TROUBLE DIAGNOSIS
CVT-63
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CVT
Revision: June 20062007 Versa
*1: Refer to CVT-33, "Malfunction Indicator Lamp (MIL)" .
*2: Models without ABS does not indicate.
How to Erase Self-diagnostic Results
1. Touch “SELF-DIAG RESULTS” on “SELECT DIAG MODE”.
2. Touch “ERASE”. (The self-diagnostic results will be erased.)
L/PRESS CON-
TROLTCM detects the unexpected line pressure P1745 —CVT-163
STEP MOTR
CIRCEach coil of the step motor is not energized properly due to
an open or a shortP1777 P1777CVT-164
STEP MOTR/FNCThere is a great difference between the number of steps for
the stepping motor and for the actual gear ratioP1778 P1778CVT-168
NO DTC IS
DETECTED: FUR-
THER TESTING
MAY BE
REQUIREDNo NG item has been detected X X — Items (CONSULT-
II screen terms)Malfunction is detected when...TCM self-
diagnosisOBD-II (DTC)
Reference
page “TRANS-
MISSION”
with CON-
SULT-IIMIL indicator
lamp*1,
“ENGINE” with
CONSULT-II or
GST
BCIA0031E
SCIA4614E

DTC P0745 LINE PRESSURE SOLENOID VALVE
CVT-113
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CVT
Revision: June 20062007 Versa
DTC P0745 LINE PRESSURE SOLENOID VALVEPFP:31940
DescriptionUCS0060N

The pressure control solenoid valve A (line pressure solenoid valve) in included in the control valve
assembly.

The pressure control solenoid valve A (line pressure solenoid valve) regulates the oil pump discharge
pressure to suit the driving condition in response to a signal sent from the TCM.
CONSULT-II Reference ValueUCS0060O
Remarks: Specification data are reference values.
On Board Diagnosis LogicUCS0060P

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P0745 L/PRESS SOL/CIRC” with CONSULT-II is detected under the following
conditions.
–TCM detects an improper voltage drop when it tries to operate the solenoid valve.
–When TCM compares target value with monitor value and detects an irregularity.
Possible CauseUCS0060Q

Harness or connectors
(Solenoid circuit is open or shorted.)

Pressure control solenoid valve A (Line pressure solenoid valve)
DTC Confirmation ProcedureUCS0060R
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode for
“TRANSMISSION” with CONSULT-II.
2. Start engine and wait at least 5 seconds.
3. If DTC is detected, go to CVT-115, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II”.
Item name Condition Display value (Approx.)
ISOLT2Release your foot from the accelerator pedal. 0.8 A
Press the accelerator pedal all the way down. 0.0 A
BCIA0031E

CVT-118
DTC P0746 PRESSURE CONTROL SOLENOID A PERFORMANCE (LINE PRES-
SURE SOLENOID VALVE)
Revision: June 20062007 Versa
DTC P0746 PRESSURE CONTROL SOLENOID A PERFORMANCE (LINE PRES-
SURE SOLENOID VALVE)
PFP:31941
DescriptionUCS0060V

The pressure control solenoid valve A (line pressure solenoid valve) are included in the control valve
assembly.

The pressure control solenoid valve A (line pressure solenoid valve) regulates the oil pump discharge
pressure to suit the driving condition in response to a signal sent from the TCM.
CONSULT-II Reference ValueUCS0060W
Remarks: Specification data are reference values.
On Board Diagnosis LogicUCS0060X

This is an OBD-II self-diagnostic item.

Diagnostic trouble code “P0746 PRS CNT SOL/A FCTN” with CONSULT-II is detected under the following
conditions.
–Unexpected gear ratio was detected in the LOW side due to excessively low line pressure.
Possible CauseUCS0060Y

Line pressure control system

Output speed sensor (Secondary speed sensor)

Input speed sensor (Primary speed sensor)
DTC Confirmation ProcedureUCS0060Z
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch OFF and
wait at least 10 seconds before performing the next test.
After the repair, touch “ERASE” on “SELF-DIAG RESULTS” and then perform the following procedure to con-
firm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch ON and select “DATA MONITOR” mode for
“TRANSMISSION” with CONSULT-II.
2. Start engine and maintain the following conditions for at least 10
consecutive seconds. Test start from 0 km/h (0 MPH).
ATF TEMP SEN: 1.0 - 2.0 V
ACC PEDAL OPEN: More than 1.0/8
RANGE: “D” position
VEHICLE SPEED: 10 km/h (6 MPH) More than
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
3. If DTC is detected, go to CVT-119, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II”.
Item name Condition Display value (Approx.)
PRI PRESS “N” position idle 0.4 MPa
BCIA0031E