2006 INFINITI FX35 engine control system

A/T CONTROL SYSTEM AT-25
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Revision: 2006 December 2006 FX35/FX45
“M1” Position

The front brake fastens the front sun gear.

The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.

High and low reverse clutch connects the rear sun gear and the mid sun gear.

The low coast brake fastens the mid sun gear.

During deceleration, the low coast brake regulates forward rotation of the mid sun gear and the engine
brake functions.
1. Front brake 2. Input clutch 3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear 12. Input shaft
13. Mid internal gear 14. Front internal gear 15. Rear carrier
16. Rear sun gear 17. Mid sun gear 18. Front carrier
19. Mid carrier 20. Rear internal gear 21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1513E

AT-26
A/T CONTROL SYSTEM
Revision: 2006 December 2006 FX35/FX45
“D2 ” Position

The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.

The 3rd one-way clutch regulates reverse rotation of the front sun gear.

The direct clutch is coupled, and the rear carrier and rear sun gear are connected.

During deceleration, the mid sun gear turns forward, so the forward one-way clutch idles and engine
brake is not activated.
1. Front brake 2. Input clutch 3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear 12. Input shaft
13. Mid internal gear 14. Front internal gear 15. Rear carrier
16. Rear sun gear 17. Mid sun gear 18. Front carrier
19. Mid carrier 20. Rear internal gear 21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1514E

A/T CONTROL SYSTEM AT-27
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Revision: 2006 December 2006 FX35/FX45
“M2” Position

The front brake fastens the front sun gear.

The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.

The direct clutch is coupled, and the rear carrier and rear sun gear are connected.

The low coast brake fastens the mid sun gear.

During deceleration, the low coast brake regulates forward rotation of the mid sun gear and the engine
brake functions.
1. Front brake 2. Input clutch 3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear 12. Input shaft
13. Mid internal gear 14. Front internal gear 15. Rear carrier
16. Rear sun gear 17. Mid sun gear 18. Front carrier
19. Mid carrier 20. Rear internal gear 21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1515E

AT-32
A/T CONTROL SYSTEM
Revision: 2006 December 2006 FX35/FX45
TCM FunctionNCS001AZ
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 signal
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Revolution sensor
Vehicle speed signal
Manual mode switch signal
Stop lamp switch signal
Turbine revolution sensor
ATF pressure switch Shift 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 system Input 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
Starter relay
Back-up lamp relay
SCIA5325E

A/T CONTROL SYSTEM AT-33
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Revision: 2006 December 2006 FX35/FX45
CAN CommunicationNCS001B0
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 TCMNCS001B1
*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: Used as a condition for starting self-diagnostics; if self-diagnostics are not started, it is judged that there is some kin d of error.
*5: Input by CAN communications
*6: Output by CAN communications Control item
Line
pressure control Vehicle
speed
control Shift
control Lock-up
control Engine
brake
control Fail-safe
function (*3) Self-diag-
nostics
function
Input Accelerator pedal position signal
(*5)XXXXXXX
Vehicle speed sensor A/T
(revolution sensor) XXXXXXX
Vehicle speed sensor MTR
(*1) (*5)X
Closed throttle position signal
(*5)X (*2) X X X X (*4)
Wide open throttle position signal
(*5)XX (*4)
Turbine revolution sensor 1 X X X X X
Turbine revolution sensor 2
(for 4th speed only) X XXXX
Engine speed signals
(*5)XXXXXXX
Stop lamp switch signal
(*5)XXX X (*4)
A/T fluid temperature sensors 1, 2XXXX XX
ASCD or
ICC Operation signal
(*5)XXX
Overdrive cancel
signal
(*5)X
Out-
put Direct 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 XXXXXXX
TCC solenoid X X X
Self-diagnostics table
(*6)X
Sta rter rela y XX

AT-34
A/T CONTROL SYSTEM
Revision: 2006 December 2006 FX35/FX45
Line Pressure ControlNCS001B2

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.

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.
LINE PRESSURE CONTROL IS BASED ON THE TCM LINE PRESSURE CHARACTERISTIC
PATTERN

The TCM has stored in memory a number of patterns for the optimum line pressure characteristic for the
driving state.

In order to obtain the most appropriate line pressure characteristic to meet the current driving state, the
TCM controls the line pressure solenoid current valve and thus controls the line pressure.
Normal Control
Each clutch is adjusted to the necessary pressure to match the
engine drive force.
Back-up Control (Engine Brake)
When the select operation is performed during driving and the trans-
mission is shifted down, the line pressure is set according to the
vehicle speed.
PCIA0007E
PCIA0008E
PCIA0009E

A/T CONTROL SYSTEM AT-35
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Revision: 2006 December 2006 FX35/FX45
During Shift Change
The necessary and adequate line pressure for shift change is set.
For this reason, line pressure pattern setting corresponds to input
torque and gearshift selection. Also, line pressure characteristic is
set according to engine speed, during engine brake operation.
At Low Fluid Temperature
When the A/T fluid temperature drops below the prescribed tempera-
ture, in order to speed up the action of each friction element, the line
pressure is set higher than the normal line pressure characteristic.
Shift ControlNCS001B3
The clutch pressure control solenoid is controlled by the signals from the switches and sensors. Thus, the
clutch pressure is adjusted to be appropriate to the engine load state and vehicle driving state. It becomes
possible to finely control the clutch hydraulic pressure with high precision and a smoother shift change charac-
teristic is attained.
SHIFT CHANGE
The clutch is controlled with the optimum timing and oil pressure by the engine speed, engine torque informa-
tion, etc.
PCIA0010E
PCIA0011E
PCIA0012E

AT-36
A/T CONTROL SYSTEM
Revision: 2006 December 2006 FX35/FX45
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.
BLIPPING CONTROL
This system makes transmission clutch engage readily by controlling (synchronizing) engine revolution
according to the (calculation of) engine revolution after shifting down.

“BLIPPING CONTROL” functions.
–When downshifting by accelerator pedal depression at “D” position.
–When downshifting under the manual mode.

TCM selects “BLIPPING CONTROL” or “NORMAL SHIFT CONTROL” according to the gear position, the
select lever position, the engine torque and the speed when accelerating by accelerator pedal depression.

Revolution control demand signal is transmitted from TCM to ECM under “BLIPPING CONTROL”.

TCM synchronizes engine revolution according to the revolution control demand signal.
Shift Change System Diagram
PCIA0013E
SCIA6483E