lock INFINITI QX4 2005 Factory User Guide

PREPARATION
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—
(J-47002)
Transmission jack adapter kit
1. —
(J-47002-2)
Center bracket
2. —
(J-47002-3)
Adapter plate
3. —
(J-47002-4)
Adapter blockAssist in removal of transmission and transfer
case as one assembly using only one trans-
mission jack.
—
(J-47245)
Ring gear stopperRemoving and installing crankshaft pulley Tool number
(Kent-Moore No.)
Tool nameDescription
W CIA0499E
LBIA0451E

A/T FLUID
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A/T FLUIDPFP:KLE40
Changing A/T FluidECS00CDQ
Refer to MA-24, "Changing A/T Fluid" .
Checking A/T FluidECS0 0CD R
Refer to MA-22, "Checking A/T Fluid" .
A/T Fluid Cooler CleaningECS00CDS
Whenever an automatic transmission is repaired, overhauled, or replaced, the A/T fluid cooler mounted in the
radiator must be inspected and cleaned.
Metal debris and friction material, if present, can become trapped in the A/T fluid cooler. This debris can con-
taminate the newly serviced A/T or, in severe cases, can block or restrict the flow of A/T fluid. In either case,
malfunction of the newly serviced A/T may result.
Debris, if present, may build up as A/T 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.
A/T FLUID COOLER CLEANING PROCEDURE
1. Position an oil pan under the automatic transmission's inlet and outlet cooler hoses.
2. Identify the inlet and outlet fluid cooler hoses.
3. 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.
4. Allow any A/T fluid that remains in the cooler hoses to drain into
the oil pan.
5. 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 cooler cleaner only with adequate ventilation.

Avoid contact with eyes and skin.

Do not breath vapors or spray mist.
6. 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 fluid flows out of the cooler inlet hose for 5 seconds.
7. Insert the tip of an air gun into the end of the cooler outlet hose.
8. Wrap a shop rag around the air gun tip and of the cooler outlet
hose.
SCIA3830E
SCIA3831E
SCIA3832E

A/T CONTROL SYSTEM
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CLUTCH AND BAND CHART

—Operates

—Operates during “progressive” acceleration.

—Operates and effects power transmission while coasting.

—Line pressure is applied but does not affect power transmission.

—Operates under conditions shown in HLR/C Operating Condition

—Operates under conditions shown in LC/B Operating Condition. Delay control is applied during D (4,3,2,1)
N shift. Shift position I/C HLR/C D/C R/B FR/B LC/B Fwd/B1st
OWCFwd
OWC3rd
OWCRemarks
PPARK POSITION
RREVERSE
POSITION
NNEUTRAL POSI-
TION
D1st
Automatic shift
1⇔2⇔3⇔4⇔5 2nd
3rd
4th
5th
1st
42nd
Automatic shift
3rd1⇔2⇔3⇔4
4th
31st
Automatic shift
1⇔2⇔3⇐4 2nd
3rd
4th
21st
Automatic shift
1⇔2⇐3⇐4 2nd
3rd
4th
11st
Locks (held sta-
tionary in 1st
gear)
1⇐2⇐3⇐4 2nd
3rd
4th

A/T CONTROL SYSTEM
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TCM FunctionECS00CDW
The function of the TCM is to:

Receive input signals sent from various switches and sensors.

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

Send required output signals to the respective solenoids.
CONTROL SYSTEM OUTLINE
The automatic transmission senses vehicle operating conditions through various sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
CONTROL SYSTEM DIAGRAM
SENSORS (or SIGNALS)


TCM


ACTUATORS
PNP switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Stop lamp switch signal
Turbine revolution sensor
1st position switch signal
4th position switch signal
ATF pressure switch signal
Tow mode switch signalShift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-II communication line
Duet-EA control
CAN systemInput clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch
solenoid valve
Low coast brake solenoid valve
Torque converter clutch solenoid
valve
Line pressure solenoid valve
A/T CHECK indicator lamp
Sta rte r re lay
Back-up lamp relay
SCIA5624E

AT-30
A/T CONTROL SYSTEM
Revision: October 20052005 QX56
CAN CommunicationECS00CDX
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-5,
"CAN COMMUNICATION" .
Input/Output Signal of TCMECS00CDY
*1: Spare for vehicle speed sensor·A/T (revolution sensor)
*2: Spare for accelerator pedal position signal
*3: If these input and output signals are different, the TCM triggers the fail-safe function.
*4: CAN communicationsControl itemLine
pressure
controlVehicle
speed
controlShift
controlLock-up
controlEngine
brake
controlFail-safe
function
(*3)Self-diag-
nostics
function
InputAccelerator pedal position signal
(*4)XXXXXXX
Vehicle speed sensor A/T
(revolution sensor)XXXX XX
Vehicle speed sensor MTR
(*1) (*4)XXXX X
Closed throttle position signal
(*4)(*2) X (*2) X X (*2) X X
Wide open throttle position signal
(*4)(*2) X (*2) X (*2) X X
Turbine revolution sensor 1 X X X X X
Turbine revolution sensor 2
(for 4th speed only)XX X XX
Engine speed signals
(*4)XX
PNP switch XXXXXXX
A/T fluid temperature sensors 1, 2 X X X X X X X
ASCDOperation signal
(*4)XXXX
Overdrive cancel
signal
(*4)XXX
TCM power supply voltage signal X X X X X X
Out-
putDirect clutch solenoid (ATF pres-
sure switch 5)XX XX
Input clutch solenoid (ATF pressure
switch 3)XX XX
High and low reverse clutch sole-
noid (ATF pressure switch 6)XX XX
Front brake solenoid (ATF pressure
switch 1)XX XX
Low coast brake solenoid (ATF
pressure switch 2)XX XXX
Line pressure solenoid X X X X X X X
TCC solenoid X X X
Starte r re la yXX

A/T CONTROL SYSTEM
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Shift Change System Diagram
*1: Full phase real-time feedback control monitors movement of gear ratio at gear change, and controls oil
pressure at real-time to achieve the best gear ratio.
Lock-up ControlECS00CE1
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, and the torque converter clutch control valve engages or releases
the torque converter clutch piston.
Lock-up Operation Condition Table
TORQUE CONVERTER CLUTCH CONTROL VALVE CONTROL
Lock-up 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.
PCIA0013E
Select lever D position 4 position 3 position 2 position
Gear position 5 4 4 3 2
Lock-up×–×××
Slip lock-up××–––
PCIA0014E

AT-34
A/T CONTROL SYSTEM
Revision: October 20052005 QX56
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.
SMOOTH LOCK-UP CONTROL
When shifting from the lock-up released state to the lock-up applied state, the current output to the torque con-
verter clutch solenoid is controlled with the TCM. In this way, when shifting to the lock-up applied state, the
torque converter clutch is temporarily set to the half-clutched state to reduce the shock.
Half-clutched State

The current output from the TCM to the torque converter clutch solenoid is varied to gradually increase
the torque converter clutch solenoid pressure.
In this way, the lock-up apply pressure gradually rises and while the torque converter clutch piston is put
into half-clutched status, the torque converter clutch piston operating pressure is increased and the cou-
pling is completed smoothly.
Slip Lock-up Control

In the slip region, the torque converter clutch solenoid current is controlled with the TCM to put it into the
half-clutched state. This absorbs the engine torque fluctuation and lock-up operates from low speed.
This raises the fuel efficiency for 4th and 5th gears at both low speed and when the accelerator has a low
degree of opening.

A/T CONTROL SYSTEM
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Engine Brake ControlECS00CE2

The forward one-way clutch transmits the drive force from the engine to the rear wheels. But the reverse
drive from the rear wheels is not transmitted to the engine because the one-way clutch is idling.
Therefore, the low coast brake solenoid is operated to prevent the forward one-way clutch from idling and
the engine brake is operated in the same manner as conventionally.

The operation of the low coast brake solenoid switches the low coast brake switching valve and controls
the coupling and releasing of the low coast brake.
The low coast brake reducing valve controls the low coast brake coupling force.
Control ValveECS00CE3
FUNCTION OF CONTROL VALVE
SCIA1520E
Name Function
Torque converter regulator valveIn order to prevent the pressure supplied to the torque converter from being excessive,
the line pressure is adjusted to the optimum pressure (torque converter operating pres-
sure).
Pressure regulator valve
Pressure regulator plug
Pressure regulator sleeveAdjusts the oil discharged from the oil pump to the optimum pressure (line pressure) for
the driving state.
Front brake control valveWhen the front brake is coupled, adjusts the line pressure to the optimum pressure
(front brake pressure) and supplies it to the front brake. (In 1st, 2nd, 3rd, and 5th gears,
adjusts the clutch pressure.)
Accumulator control valveAdjusts the pressure (accumulator control pressure) acting on the accumulator piston
and low coast reducing valve to the pressure appropriate to the driving state.
Pilot valve AAdjusts the line pressure and produces the constant pressure (pilot pressure) required
for line pressure control, shift change control, and lock-up control.
Pilot valve BAdjusts the line pressure and produces the constant pressure (pilot pressure) required
for shift change control.
Low coast brake switching valve During engine braking, supplies the line pressure to the low coast brake reducing valve.
Low coast brake reducing valveWhen the low coast brake is coupled, adjusts the line pressure to the optimum pressure
(low coast brake pressure) and supplies it to the low coast brake.
N-R accumulator Produces the stabilizing pressure for when N-R is selected.
Direct clutch piston switching valve Operates in 4th gear and switches the direct clutch coupling capacity.
High and low reverse clutch control valveWhen the high and low reverse clutch is coupled, adjusts the line pressure to the opti-
mum pressure (high and low reverse clutch pressure) and supplies it to the high and low
reverse clutch. (In 1st, 3rd, 4th and 5th gears, adjusts the clutch pressure.)

AT-36
A/T CONTROL SYSTEM
Revision: October 20052005 QX56
FUNCTION OF PRESSURE SWITCH
Input clutch control valveWhen the input clutch is coupled, adjusts the line pressure to the optimum pressure
(input clutch pressure) and supplies it to the input clutch. (In 4th and 5th gears, adjusts
the clutch pressure.)
Direct clutch control valveWhen the direct clutch is coupled, adjusts the line pressure to the optimum pressure
(direct clutch pressure) and supplies it to the direct clutch. (In 2nd, 3rd, and 4th gears,
adjusts the clutch pressure.)
TCC control valve
TCC control plug
TCC control sleeveSwitches the lock-up to operating or released. Also, by performing the lock-up operation
transiently, lock-up smoothly.
Torque converter lubrication valveOperates during lock-up to switch the torque converter, cooling, and lubrication system
oil path.
Cool bypass valve Allows excess oil to bypass cooler circuit without being fed into it.
Line pressure relief valve Discharges excess oil from line pressure circuit.
N-D accumulator Produces the stabilizing pressure for when N-D is selected.
Manual valveSends line pressure to each circuit according to the select position. The circuits to which
the line pressure is not sent drain. Name Function
Name Function
Pressure switch 1 (FR/B)Detects any malfunction in the front brake hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
Pressure switch 2 (LC/B)Detects any malfunction in the low coast brake hydraulic pressure. When it detects any
malfunction, it puts the system into fail-safe mode.
Pressure switch 3 (I/C)Detects any malfunction in the input clutch hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
Pressure switch 5 (D/C)Detects any malfunction in the direct clutch hydraulic pressure. When it detects any mal-
function, it puts the system into fail-safe mode.
Pressure switch 6 (HLR/C)Detects any malfunction in the high and low reverse clutch hydraulic pressure. When it
detects any malfunction, it puts the system into fail-safe mode.

AT-42
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
A/T Interlock

If there is an A/T interlock judgment malfunction, the transmission is fixed in 2nd gear to make driving pos-
sible.
NOTE:
When the vehicle is driven fixed in 2nd gear, a turbine revolution sensor malfunction is displayed,
but this is not a turbine revolution sensor malfunction.

When the coupling pattern below is detected, the fail-safe action corresponding to the pattern is per-
formed.
A/T INTERLOCK COUPLING PATTERN TABLE

: NG X: OK
A/T 1st Engine Braking

When there is an A/T first gear engine brake judgment malfunction, the low coast brake solenoid is
switched “OFF” to avoid the engine brake operation.
Line Pressure Solenoid

The solenoid is switched “OFF” and the line pressure is set to the maximum hydraulic pressure to make
driving possible.
Torque Converter Clutch Solenoid

The solenoid is switched “OFF” to release the lock-up.
Low Coast Brake Solenoid

When a (electrical or functional) malfunction occurs, in order to make driving possible, the engine brake is
not applied in 1st and 2nd gear.
Input Clutch Solenoid

If a (electrical or functional) malfunction occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4th gear to make driving possible.
Direct Clutch Solenoid

If a (electrical or functional) malfunction occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4th gear to make driving possible.
Front Brake Solenoid

If a (electrical or functional) malfunction occurs with the solenoid “ON”, in order to make driving possible,
the A/T is held in 5th gear; if the solenoid is OFF, 4th gear.
High and Low Reverse Clutch Solenoid

If a (electrical or functional) malfunction occurs with the solenoid either “ON” or “OFF”, the transmission is
held in 4th gear to make driving possible.
Turbine Revolution Sensor 1 or 2

The control is the same as if there were no turbine revolution sensors, 5th gear is prohibited.
Gear positionATF pressure switch output
Fail-safe
functionClutch pressure output pattern after fail-safe func-
tion
SW3
(I/C)SW6
(HLR/
C)SW5
(D/C)SW1
(FR/B)SW2
(LC/B)I/C HLR/C D/C FR/B LC/B L/U
A/T inter-
lock cou-
pling pattern3rd – X X –
Held in
2nd gearOFF OFF ON OFF OFF OFF
4th – X X –
Held in
2nd gearOFF OFF ON OFF OFF OFF
5th X X – X
Held in
2nd gearOFF OFF ON OFF OFF OFF