Nissan Murano Z50 (2006 year). Manual — part 57

CVT FLUID

CVT-17

CVT

Revision: 2006 August

2006 Murano

CVT Fluid Cooler Cleaning

NCS0012F

Whenever an automatic transaxle is repaired, overhauled, or replaced, the CVT fluid cooler mounted in the
radiator must be inspected and cleaned.
Metal debris and friction material, if present, can be trapped or become deposit in the CVT fluid cooler. This
debris can contaminate the newly serviced CVT or, in severe cases, can block or restrict the flow of CVT fluid.
In either case, malfunction of the newly serviced CVT may occur.
Debris, if present, may deposit as CVT fluid enters the cooler inlet. It will be necessary to back flush the cooler
through the cooler outlet in order to flush out any built up debris.

CVT FLUID COOLER CLEANING PROCEDURE

Position an oil pan under the transaxle's inlet and outlet cooler hoses.

Identify the inlet and outlet fluid cooler hoses.

Disconnect the fluid cooler inlet and outlet rubber hoses from the
steel cooler tubes or bypass valve.

NOTE:
Replace the cooler hoses if rubber material from the hose
remains on the tube fitting.

Allow any CVT fluid that remains in the cooler hoses to drain into
the oil pan.

Insert the extension adapter hose of a can of Transmission
Cooler Cleaner (Nissan P/N 999MP-AM006) into the cooler out-
let hose.

CAUTION:

●

Wear safety glasses and rubber gloves when spraying
the Transmission Cooler Cleaner.

●

Spray Transmission Cooler Cleaner only with adequate
ventilation.

●

Avoid contact with eyes and skin.

●

Do not breath vapors or spray mist.

Hold the hose and can as high as possible and spray Transmis-
sion Cooler Cleaner in a continuous stream into the cooler outlet hose until CVT fluid flows out of the
cooler inlet hose for 5 seconds.

Insert the tip of an air gun into the end of the cooler outlet hose.

Wrap a shop rag around the air gun tip and of the cooler outlet
hose.

Blow compressed air regulated to 5 to 9 kg/cm

(70 to 130 psi)

through the cooler outlet hose for 10 seconds to force out any
remaining CVT fluid.

10. Repeat steps 5 through 9 three additional times.

11. Position an oil pan under the banjo bolts that connect the CVT

fluid cooler steel lines to the transaxle.

12. Remove the banjo bolts.

13. Flush each steel line from the cooler side back toward the tran-

saxle by spraying Transmission Cooler Cleaner in a continuous stream for 5 seconds.

14. Blow compressed air regulated to 5 to 9 kg/cm

(70 to 130 psi) through each steel line from the cooler

side back toward the transaxle for 10 seconds to force out any remaining CVT fluid.

15. Ensure all debris is removed from the steel cooler lines.

16. Ensure all debris is removed from the banjo bolts and fittings.
17. Perform

CVT-18, "CVT FLUID COOLER DIAGNOSIS PROCEDURE"

SCIA4421E

SCIA4422E

SCIA4423E

CVT-18

CVT FLUID

Revision: 2006 August

2006 Murano

CVT FLUID COOLER DIAGNOSIS PROCEDURE

NOTE:
Insufficient cleaning of the cooler inlet hose exterior may lead to inaccurate debris identification.
1.

Position an oil pan under the transaxle's inlet and outlet cooler hoses.

Clean the exterior and tip of the cooler inlet hose.

Insert the extension adapter hose of a can of Transmission
Cooler Cleaner (Nissan P/N 999MP-AM006) into the cooler out-
let hose.

CAUTION:

●

Wear safety glasses and rubber gloves when spraying
the Transmission Cooler Cleaner.

●

Spray Transmission Cooler Cleaner only with adequate
ventilation.

●

Avoid contact with eyes and skin.

●

Do not breath vapors or spray mist.

Hold the hose and can as high as possible and spray Transmis-
sion Cooler Cleaner in a continuous stream into the cooler outlet hose until CVT fluid flows out of the
cooler inlet hose for 5 seconds.

Tie a common white, basket-type coffee filter to the end of the
cooler inlet hose.

Insert the tip of an air gun into the end of the cooler outlet hose.

Wrap a shop rag around the air gun tip and end of cooler outlet
hose.

Blow compressed air regulated to 5 to 9 kg/cm

(70 to 130 psi)

through the cooler outlet hose to force any remaining CVT fluid
into the coffee filter.

Remove the coffee filter from the end of the cooler inlet hose.

10. Perform

CVT-19, "CVT FLUID COOLER INSPECTION PROCE-

DURE"

SCIA4421E

SCIA4424E

SCIA4425E

CVT FLUID

CVT-19

CVT

Revision: 2006 August

2006 Murano

CVT FLUID COOLER INSPECTION PROCEDURE

Inspect the coffee filter for debris.

If small metal debris less than 1 mm (0.040 in) in size or metal
powder is found in the coffee filter, this is normal. If normal
debris is found, the CVT fluid cooler/radiator can be re-used and
the procedure is ended.

If one or more pieces of debris are found that are over 1 mm
(0.040 in) in size and/or peeled clutch facing material is found in
the coffee filter, the fluid cooler is not serviceable. The radiator/
fluid cooler must be replaced and the inspection procedure is
ended.

CVT FLUID COOLER FINAL INSPECTION

After performing all procedures, ensure that all remaining oil is cleaned from all components.

SCIA2967E

SCIA7031E

CVT-20

CVT SYSTEM

Revision: 2006 August

2006 Murano

CVT SYSTEM

PFP:31036

Cross-sectional View - RE0F09A

NCS0012G

Converter housing

Oil pump

Forward clutch

Reverse brake

Planetary carrier

Primary pulley

Steel belt

Sun gear

Side cover

10. Internal gear

11.

Secondary pulley

12. Final gear

13. Differential case

14. Idler gear

15. Reduction gear

16. Taper roller bearing

17. Output gear

18. Parking gear

19. Input shaft

20. Torque converter

SCIA4837E

CVT SYSTEM

CVT-21

CVT

Revision: 2006 August

2006 Murano

Control System

NCS0012H

SCIA6883E

CVT-22

CVT SYSTEM

Revision: 2006 August

2006 Murano

Hydraulic Control System

NCS0012I

SCIA1807E

CVT SYSTEM

CVT-23

CVT

Revision: 2006 August

2006 Murano

TCM Function

NCS0012J

The function of the TCM is to:

●

Receive input signals sent from various switches and sensors.

●

Determine required line pressure, shifting point, and lock-up operation.

●

Send required output signals to the step motor and the respective solenoids.

CONTROL SYSTEM OUTLINE

The CVT senses vehicle operating conditions through various sensors. It always controls the optimum shift
position and reduces shifting and lock-up shocks.

*: Without manual mode.

CONTROL SYSTEM DIAGRAM

SENSORS (or SIGNAL)

TCM

ACTUATORS

PNP switch
Accelerator pedal position signal
Closed throttle position signal
Engine speed signal
CVT fluid temperature sensor
Vehicle speed signal
Manual mode signal
Second position signal*
Stop lamp switch signal
Primary speed sensor
Secondary speed sensor
Primary pressure sensor
Secondary pressure sensor

Shift control
Line pressure control
Primary pressure control
Secondary pressure control
Lock-up control
Engine brake control
Vehicle speed control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN system
On board diagnosis

Step motor
Torque converter clutch solenoid
valve
Lock-up select solenoid valve
Line pressure solenoid valve
Secondary pressure solenoid
valve
Manual mode indicator
Second position indicator*
CVT position indicator
CVT indicator lamp
Starter relay

SCIA7495E

CVT-24

CVT SYSTEM

Revision: 2006 August

2006 Murano

CAN Communication

NCS0012K

SYSTEM DESCRIPTION

CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN-H line, CAN-L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only. For details, refer to

LAN-32,

"CAN Communication Unit"

Input/Output Signal of TCM

NCS0012L

*1: Input by CAN communications.
*2: If these input and output signals are different, the TCM triggers the fail-safe function.
*3: Without manual mode.

Control item

Fluid

pressure

control

Select con-

trol

Shift con-

trol

Lock-up

control

CAN com-

munication

control

Fail-safe

function

(*2)

Input

PNP switch

Accelerator pedal position signal

(*1)

Closed throttle position signal

(*1)

Engine speed signal

(*1)

CVT fluid temperature sensor

Manual mode signal

(*1)

Second position signal

(*1)

(*3)

Stop lamp switch signal

(*1)

Primary speed sensor

Secondary speed sensor

Primary pressure sensor

Secondary pressure sensor

TCM power supply voltage signal

Out-
put

Step motor

TCC solenoid valve

Lock-up select solenoid valve

Line pressure solenoid valve

Secondary pressure solenoid valve

CVT SYSTEM

CVT-25

CVT

Revision: 2006 August

2006 Murano

Line Pressure and Secondary Pressure Control

NCS0012M

●

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 Control

NCS0012N

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

SCIA8097E

CVT-26

CVT SYSTEM

Revision: 2006 August

2006 Murano

NOTE:
The gear ratio is set for every position separately.

“D” POSITION

Shifting over all the ranges of gear ratios from the lowest to the high-
est.

“S” POSITION (WITHOUT MANUAL MODE)

Use this position for the improved engine braking.

“L” POSITION (WITHOUT MANUAL MODE)

By limiting the gear range to the lowest position, the strong driving
force and the engine brake can be secured.

“M” POSITION

When the selector lever is put in the manual shift gate side, the fixed
changing gear line is set. By moving the selector lever to + side or -
side, the manual mode switch is changed over, and shift change like
M/T becomes possible following the changing gear set line step by
step.

DOWNHILL ENGINE BRAKE CONTROL (AUTO ENGINE BRAKE CONTROL)

When downhill is detected with the accelerator pedal released, the engine brake will be strengthened up by
downshifting so as not to accelerate the vehicle more than necessary.

ACCELERATION CONTROL

According to vehicle speed and a change of accelerator pedal angle, driver's request for acceleration and driv-
ing scene are judged. This function assists improvement in acceleration feeling by making the engine speed
proportionate to the vehicle speed. And a shift map which can gain a larger driving force is available for com-
patibility of mileage with driveability.

SCIA1953E

SCIA1955E

SCIA4582E

CVT SYSTEM

CVT-27

CVT

Revision: 2006 August

2006 Murano

Lock-up and Select Control

NCS0012O

●

The torque converter clutch piston in the torque converter is engaged to eliminate torque converter slip to
increase power transmission efficiency.

●

The torque converter clutch control valve operation is controlled by the torque converter clutch solenoid
valve, which is controlled by a signal from TCM. The torque converter clutch control valve engages or
releases the torque converter clutch piston.

●

When shifting between “N” (“P”)

⇔

“D” (“R”), torque converter clutch solenoid controls engagement power

of forward clutch and reverse brake.

●

The lock-up applied gear range was expanded by locking up the
torque converter at a lower vehicle speed than conventional
CVT models.

TORQUE CONVERTER CLUTCH AND SELECT CONTROL VALVE CONTROL
Lock-up and Select Control System Diagram

Lock-up Released

In the lock-up released state, the torque converter clutch control valve is set into the unlocked state by the
torque converter clutch solenoid and the lock-up apply pressure is drained.
In this way, the torque converter clutch piston is not coupled.

Lock-up Applied

In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the torque
converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.

Select Control

When shifting between “N” (“P”)

⇔

“D” (“R”), optimize the operating pressure on the basis of the throttle posi-

tion, the engine speed, and the secondary pulley (output) revolution speed to lessen the shift shock.

SCIA1958E

SCIA2374E

CVT-28

CVT SYSTEM

Revision: 2006 August

2006 Murano

Control Valve

NCS0012P

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 valve

Controls 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 valve

Controls 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 valve

Transmits 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 valve

Switches 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.

ON BOARD DIAGNOSTIC (OBD) SYSTEM

CVT-29

CVT

Revision: 2006 August

2006 Murano

ON BOARD DIAGNOSTIC (OBD) SYSTEM

PFP:00028

Introduction

NCS0012Q

The CVT system has two self-diagnostic systems.
The first is the emission-related on board diagnostic system (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MIL (malfunction indicator lamp) and is stored as a DTC in
the ECM memory, and the TCM memory.
The second is the TCM original self-diagnosis performed by the TCM. The malfunction is stored in the TCM
memory. The detected items are overlapped with OBD-II self-diagnostic items. For detail, refer to

CVT-65,

"Display Items List"

OBD-II Function for CVT System

NCS0012R

The ECM provides emission-related on board diagnostic (OBD-II) functions for the CVT system. One function
is to receive a signal from the TCM used with OBD-related parts of the CVT system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-related part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indicator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to CVT system parts.

One or Two Trip Detection Logic of OBD-II

NCS0012S

ONE TRIP DETECTION LOGIC

If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.

TWO TRIP DETECTION LOGIC

When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — 1st trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd trip
The “trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.

OBD-II Diagnostic Trouble Code (DTC)

NCS0012T

HOW TO READ DTC AND 1ST TRIP DTC

DTC and 1st trip DTC can be read by the following methods.
(

with CONSULT-II or

GST) CONSULT-II or GST (Generic Scan Tool) Examples: P0705, P0720 etc.

These DTC are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)

●

1st trip DTC No. is the same as DTC No.

●

Output of the diagnostic trouble code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring
or occurred in the past and returned to normal.
CONSULT-II can identify them as shown below, therefore, CONSULT-II (if available) is recom-
mended.

A sample of CONSULT-II display for DTC and 1st trip DTC is shown
on the next page. DTC or 1st trip DTC of a malfunction is displayed
in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with CON-
SULT-II. Time data indicates how many times the vehicle was driven
after the last detection of a DTC.

BCIA0030E

CVT-30

ON BOARD DIAGNOSTIC (OBD) SYSTEM

Revision: 2006 August

2006 Murano

If the DTC is being detected currently, the time data will be “0”.

If a 1st trip DTC is stored in the ECM, the time data will be “1t”.

Freeze Frame Data and 1st Trip Freeze Frame Data

The ECM has a memory function, which stores the driving condition such as fuel system status, calculated
load value, engine coolant temperature, short term fuel trim, long term fuel trim, engine speed and vehicle
speed at the moment the ECM detects a malfunction.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data,
and the data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II
or GST. The 1st trip freeze frame data can only be displayed on the CONSULT-II screen, not on the GST. For
details, refer to

EC-112, "CONSULT-II Function (ENGINE)"

Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data, and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.

Both 1st trip freeze frame data and freeze frame data (along with the DTC) are cleared when the ECM mem-
ory is erased.

HOW TO ERASE DTC

The diagnostic trouble code can be erased by CONSULT-II, GST or ECM DIAGNOSTIC TEST MODE as
described following.

●

If the battery cable is disconnected, the diagnostic trouble code will be lost within 24 hours.

●

When you erase the DTC, using CONSULT-II or GST is easier and quicker than switching the mode
selector on the ECM.

The following emission-related diagnostic information is cleared from the ECM memory when erasing DTC
related to OBD-II. For details, refer to

EC-46, "Emission-Related Diagnostic Information"

●

Diagnostic trouble codes (DTC)

●

1st trip diagnostic trouble codes (1st trip DTC)

●

Freeze frame data

SAT015K

SAT016K

Priority

Items

Freeze frame data

Misfire — DTC: P0300 - P0306
Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175

Except the above items (Includes CVT related items)

1st trip freeze frame data

ON BOARD DIAGNOSTIC (OBD) SYSTEM

CVT-31

CVT

Revision: 2006 August

2006 Murano

●

1st trip freeze frame data

●

System readiness test (SRT) codes

●

Test values

HOW TO ERASE DTC (WITH CONSULT-II)

●

If a DTC is displayed for both ECM and TCM, it is necessary to be erased for both ECM and TCM.

If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.

Turn CONSULT-II ON and touch “TRANSMISSION”.

Touch “SELF-DIAG RESULTS”.

Touch “ERASE”. (The DTC in the TCM will be erased.) Then touch “BACK” twice.

Touch “ENGINE”.

Touch “SELF-DIAG RESULTS”.

Touch “ERASE”. (The DTC in the ECM will be erased.)

HOW TO ERASE DTC (WITH GST)

If the ignition switch stays ON after repair work, be sure to turn ignition switch OFF once. Wait at least 10
seconds and then turn it ON (engine stopped) again.

Select Mode 4 with GST (Generic Scan Tool). For details, refer to

EC-124, "Generic Scan Tool (GST)

Function"

SCIA7508E