2011 INFINITI QX56 torque

TM-16
< SYSTEM DESCRIPTION >[7AT: RE7R01B]
STRUCTURE AND OPERATION
STRUCTURE AND OPERATION
TRANSMISSION
TRANSMISSION : Cross-Sectional ViewINFOID:0000000006226762
2WD MODELS
4WD MODELS
1. Low brake 2. Drum support 3. Reverse brake
4. Direct clutch 5. High and low reverse clutch 6. 2nd one-way clutch
7.
*1Rear carrier 8. Mid carrier 9. Input clutch
10.
*2Front sun gear 11 .*3Front carrier 12. Under drive carrier
13. 1st one-way clutch 14. Front brake 15. 2346 brake
16.
*4Input shaft 17. Torque converter 18. Oil pump
19.
*2Under drive sun gear 20.*3Under drive internal gear21.*4Front internal gear
22. Mid sun gear 23.
*1Mid internal gear 24. Rear sun gear
25. Rear internal gear 26. High and low reverse clutch hub 27. Control valve & TCM
28. Parking gear 29. Adapter case 30. Output shaft
*1: 7 and 23 are one unit.
*2: 10 and 19 are one unit.
*3: 11 and 20 are one unit.
*4: 16 and 21 are one unit.
JSDIA1852ZZ
Revision: 2010 May2011 QX56

STRUCTURE AND OPERATIONTM-17
< SYSTEM DESCRIPTION > [7AT: RE7R01B]
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EF
G H
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M A
B
TM
N
O P
1. Low brake 2. Drum support 3. Reverse brake
4. Direct clutch 5. High and low reverse clutch 6. 2nd one-way clutch
7.
*1Rear carrier 8. Mid carrier 9. Input clutch
10.
*2Front sun gear 11 .*3Front carrier 12. Under drive carrier
13. 1st one-way clutch 14. Front brake 15. 2346 brake
16.
*4Input shaft 17. Torque converter 18. Oil pump
19.
*2Under drive sun gear 20.*3Under drive internal gear21.*4Front internal gear
22. Mid sun gear 23.
*1Mid internal gear 24. Rear sun gear
25. Rear internal gear 26. High and low reverse clutch hub 27. Control valve & TCM
28. Parking gear 29. Adapter case 30. Output shaft
*1: 7 and 23 are one unit.
*2: 10 and 19 are one unit.
*3: 11 and 20 are one unit.
*4: 16 and 21 are one unit.
JSDIA1774ZZ
Revision: 2010 May2011 QX56

TM-20
< SYSTEM DESCRIPTION >[7AT: RE7R01B]
STRUCTURE AND OPERATION
Since the low brake is released, torque from the input
shaft drive is not transmitted to the output shaft.
“P” Position
JSDIA0880GB
Revision: 2010 May2011 QX56

STRUCTURE AND OPERATIONTM-21
< SYSTEM DESCRIPTION > [7AT: RE7R01B]
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B
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N
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 The same as for the “N” position, since the low brake is released, so torque from the input shaft drive is not
transmitted to the output shaft.
 The parking pawl linked with the selector lever mes hes with the parking gear and fastens the output shaft
mechanically.
“D1” Position
JSDIA1277GB
Revision: 2010 May2011 QX56

STRUCTURE AND OPERATIONTM-41
< SYSTEM DESCRIPTION > [7AT: RE7R01B]
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G H
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M A
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 Each planetary gear enters the state described below.
Front planetary gear
Under drive planetary gear
Rear planetary gear
Mid planetary gear
TRANSMISSION : Component DescriptionINFOID:0000000006226765
FLUID COOLER & FLUID WARMER SYSTEM
FLUID COOLER & FLUID WARMER SYSTEM : System DescriptionINFOID:0000000006226766
The A/T fluid temperature is controlled to an appropriate level by the A/T fluid cooler and A/T fluid warmer.
Name Front sun gear Front carrier Front internal gear
Condition — Output Input
Direction of rotation Counterclockwise revolution Clockwise revolution Clockwise revolution
Number of revolutions Deceleration from front internal
gear Deceleration from front internal
gear Same number of revolution as the
input shaft
Name Under drive sun gear Under drive carrier Under drive internal gear
Condition — Fixed Input/Output
Direction of rotation Counterclockwi se revolution — Clockwise revolution
Number of revolutions Acceleration from under drive inter-
nal gear —Same number of revolution as the
front carrier
Name Rear sun gear Rear carrier Rear internal gear
Condition Output Fixed Input
Direction of rotation Counterclockwi se revolution — Clockwise revolution
Number of revolutions Acceleration from rear internal
gear —Same number of revolution as the
under drive internal gear
Name Mid sun gear Mid carrier Mid internal gear
Condition Input Output Fixed
Direction of rotation Counterclockwise revolution Counterclockwise revolution —
Number of revolutions Same number of revolution as the
rear sun gear Deceleration from mid sun gear —
Name of the Part (Abbreviation) Function
Front brake (FR/B) Fastens the under drive carrier.
Input clutch (I/C) Connects the input shaft, the mid internal gear and the rear carrier.
Direct clutch (D/C) Connects the rear carrier and the rear sun gear.
High and low reverse clutch (HLR/C) Connects the rear sun gear and the mid sun gear.
Reverse brake (R/B) Fastens the rear carrier.
Low brake (L/B) Fastens the mid sun gear.
2346 brake (2346/B) Fastens the under drive sun gear.
1st one-way clutch (1st OWC) Allows the under drive carrier to turn freely in the forward direction but fastens it for reverse
rotation.
2nd one-way clutch (2nd OWC) Allows the rear sun gear to turn freely in the forward direction but fastens it for reverse ro-
tation.
Torque converter Amplifies driving force the engine, and transmits it to transmission input shaft.
Oil pump Driven by the engine, oil pump supplies oil to torque converter, control valve assembly, and
each lubricating system.
Revision: 2010 May2011 QX56

TM-44
< SYSTEM DESCRIPTION >[7AT: RE7R01B]
SYSTEM
SYSTEM
A/T CONTROL SYSTEM
A/T CONTROL SYSTEM : System DiagramINFOID:0000000006226767
A/T CONTROL SYSTEM : System DescriptionINFOID:0000000006226768
INPUT/OUTPUT SIGNAL CHART
SYSTEM DESCRIPTION
 The A/T senses vehicle operating conditions through vari
ous sensors or signals. It always controls the opti-
mum shift position and reduces shifting and lock-up shocks.
 Receive input signals transmitted from various switches and sensors.
 Determine required line pressure, shifting point, lock-up operation, etc.
JSDIA1853GB
Sensor (or signal)
⇒TCM function
⇒Actuator
Transmission range switch
Accelerator pedal position signal
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Output speed sensor
Vehicle speed signal
Manual mode switch signal
Stop lamp switch signal
Input speed sensor 1, 2
Yaw rate/side/decel G sensor
Tow mode switch signal Line pressure control (
TM-48
)
Shift change control ( TM-50
)
Shift pattern control ( TM-54
)
Lock-up control ( TM-56
)
Fail-safe control ( TM-45
)
Self-diagnosis ( TM-61
)
CONSULT-III communication line ( TM-61
)
CAN communication line ( TM-103
)Input clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch solenoid valve
Low brake solenoid valve
Torque converter clutch solenoid valve
Line pressure solenoid valve
Anti-interlock solenoid valve
2346 brake solenoid valve
A/T CHECK indicator lamp
Tow mode indicator lamp
Shift position indicator
Back-up lamp relay
Starter relay
Revision: 2010 May2011 QX56

SYSTEMTM-47
< SYSTEM DESCRIPTION > [7AT: RE7R01B]
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A/T CONTROL SYSTEM : Protection ControlINFOID:0000000006226770
The TCM becomes the protection control status temporar ily to protect the safety when the safety of TCM and
transmission is lost. It automatically returns to the normal status if the safety is secured.
The TCM has the following protection control.
REVERSE INHIBIT CONTROL
Intercepts the torque transmission and shift to the neutral stat us if the selector lever is shifted to “R” position
while the vehicle moves forward at the vehicle speed 10 km/h (7 MPH) or more.
1ST ENGINE BRAKE PROTECTION CONTROL
Controls the engine brake so as not to make effective by turning the front brake solenoid output to OFF when
each solenoid becomes the electricity pattern of 1st engine brake during driving at the vehicle speed 25 km/h
or more in any positions other than “R” position and 1GR.
TCM HIGH TEMPERATURE PROTECTION CONTROL
Limit the accelerator opening and forcibly control the vehi cle to the low torque driving when the electronic sub-
strate in TCM reaches the high temperature.
P1730 —  Neutral
 Manual mode is prohibited  The shifting between the gears
of 1 - 2 - 3 can be performed
 Manual mode is prohibited Locks in 1GR
 The shifting between the gears
of 2 - 3 - 4 can be performed
 The shifting between the gears
of 3 - 4 can be performed
 The shifting between the gears of 4 - 5 - 6 can be performed
 Manual mode is prohibited
P1815 — Manual mode is prohibited — Manual mode is prohibited
U0300
U1000 Between
the gears of 1 - 2 - 3  The shifting between the gears
of 1 - 2 - 3 can be performed
 Manual mode is prohibited —
 The shifting between the gears
of 1 - 2 - 3 can be performed
 Line pressure is set to the maxi-
mum hydraulic pressure
 Manual mode is prohibited
Between
the gears of 4 - 5 - 6 - 7  Fix the gear at driving
 Manual mode is prohibited
—
P0720 and
P1721 — Locks in 5GR — Locks in 5GR
DTC
Veh ic le
condition Vehicle behavior for 1st fail-safe Vehicle behavior for 2nd fail-safe Vehicle behavior for final fail-safe
Malfunction detection condition Vehicle speed: 10 km/h (7 MPH) or more
Control at malfunction Neutral
Normal return condition  Vehicle speed: 8 km/h (5 MPH) or less
and
 Engine speed: 2,200 rpm or less
Vehicle behavior  The torque transmission cannot be performed
 There is a shock just before a vehicle stop
Malfunction detection condition Select lever and gear: Any position other than “R” position and 1GR
and
 Vehicle speed: More than 25 km/h (16 MPH)
Control at malfunction Front brake solenoid output signal; OFF
Normal return condition Other than detection condition of malfunction
Vehicle behavior Does not exist
Revision: 2010 May2011 QX56

TM-48
< SYSTEM DESCRIPTION >[7AT: RE7R01B]
SYSTEM
LINE PRESSURE CONTROL
LINE PRESSURE CONTROL : System DiagramINFOID:0000000006226771
LINE PRESSURE CONTROL : System DescriptionINFOID:0000000006226772
 When an engine and A/T integrated control signal (engine
torque) equivalent to the engine drive force is
transmitted from the ECM to the TCM, the TC M controls the line pressure solenoid valve.
This line pressure solenoid controls the pressure regul ator valve as the signal pressure and adjusts the pres-
sure of the operating oil discharged from the oil pump to the line pressure most appropriate to the driving
state.
 The TCM has stored in memory a number of patterns fo r the optimum line pressure characteristic for the
driving state.
 In order to obtain the most appropriate line pressure char acteristic to meet the current driving state, the TCM
controls the line pressure solenoid current value 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)
Malfunction detection conditionTCM electronic substrate temperature
145
°C (293 °F) and 120 seconds
or
150 °C (302 °F)
Control at malfunction Accelerator opening: 0.5/8 or less
Normal return condition  TCM electronic substrate temperature: Less than 140
°C (284 °F)
and
 Vehicle speed: 5 km/h (3 MPH) or less
Vehicle behavior Accelerator opening: output torque of approximately 0.5/8
JSDIA1345GB
PCIA0008E
Revision: 2010 May2011 QX56