2010 INFINITI QX56 engine

TM-6
< BASIC INSPECTION >
DIAGNOSIS AND REPAIR WORKFLOW
>> GO TO 3.
3.CHECK DTC
1. Check DTC.
2. Perform the following procedure if DTC is detected.
• Record DTC.
• Erase DTC. Refer to TM-30, "
OBD-II Diagnostic Trouble Code (DTC)".
Is any DTC detected?
YES >> GO TO 4.
NO >> GO TO 6.
4.PERFORM DIAGNOSTIC PROCEDURE
Perform “Diagnosis Procedure” for the displayed DTC.
>> GO TO 5.
5.PERFORM DTC CONFIRMATION PROCEDURE
Perform “DTC CONFIRMATION PROCEDURE”.
Is DTC detected?
YES >> GO TO 4.
NO >> GO TO 6.
6.CHECK SYMPTOM 2
Try to confirm the symptom described by the customer.
Is any malfunction present?
YES >> GO TO 7.
NO >> INSPECTION END
7.ROAD TEST
Perform “ROAD TEST”. Refer to TM-159, "
Description".
>> GO TO 8.
8.CHECK SYMPTOM 3
Try to confirm the symptom described by the customer.
Is any malfunction present?
YES >> GO TO 2.
NO >> INSPECTION END
Diagnostic Work SheetINFOID:0000000005148506
INFORMATION FROM CUSTOMER
KEY POINTS• WHAT ..... Vehicle and A/T model
• WHEN ..... Date, Frequencies
• WHERE ..... Road conditions
• HOW ..... Operating conditions, Symptoms
Customer name MR/MS Model and Year VIN
Trans. Model EngineMileage
Malfunction Date Manuf. DateIn Service Date
Frequency † Continuous † Intermittent ( times a day)
Revision: April 20092010 QX56

DIAGNOSIS AND REPAIR WORKFLOWTM-7
< BASIC INSPECTION >
CEF
G H
I
J
K L
M A
B
TM
N
O P
DIAGNOSTIC WORK SHEET
Symptoms † Vehicle does not move. ( † Any position † Particular position)
† No up-shift ( † 1st → 2nd † 2nd → 3rd † 3rd → 4th † 4th → 5th)
† No down-shift ( † 5th → 4th † 4th → 3rd † 3rd → 2nd † 2nd → 1st)
† Lock-up malfunction
† Shift point too high or too low.
† Shift shock or slip ( † N → D † N → R † Lock-up † Any drive position)
† Noise or vibration
† No kick down
† No pattern select
† Others
()
A/T CHECK indicator lamp † Continuously lit † Not lit
Malfunction indicator lamp (MIL) † Continuously lit † Not lit
1 †
Read the item on cautions concerning fail-safe and understand the customer's com-
plaint. TM-117
2†
A/T fluid inspection, stall test and line pressure test
† A/T fluid inspection
TM-148
† Leak (Repair leak location.)
† Sta te
† Amount
† Stall test
TM-155
† Torque converter one-way clutch
† Front brake
† High and low reverse clutch
† Low coast brake
† Forward brake
† Reverse brake
† Forward one-way clutch †
1st one-way
clutch
† 3rd one-way
clutch
† Engine
† Line pressure low
† Except for input
clutch and direct
clutch, clutches and
brakes OK
† Line pressure test - Suspected part: TM-157
3†
Perform self-diagnosis. — Check detected items to repair or replace malfunctioning
part. TM-32
4†
Perform road test.
5-1 † Check before engine is started TM-159
5-2† Check at idle TM-159
5-3Cruise test †
Part 1 TM-160† Part 2 TM-162
† Part 3 TM-162
† Check malfunction phenomena to repair or replace malfunctioning part after completing all road test.
Refer to TM-121, "
Symptom Table".
5 † Drive vehicle to check that the malfunction phenomenon has been resolved.
6 † Erase the results of the self-diagnosis from the TCM and the ECM. TM-30
Revision: April 20092010 QX56

TM-12
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
Since both the forward brake and the reverse brake are released, torque from the input shaft drive is not trans-
mitted to the output shaft.
“P” Position
• The same as for the “N” position, both the forward br ake and the reverse brake are released, so torque from
the input shaft drive is not transmitted to the output shaft.
• The parking pawl linked with the select lever meshes with the parking gear and fastens the output shaft mechanically.
“D”, “4”, “3”, “2” Positions 1GR
• The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.
• The 1st one-way clutch regulates reverse rotation of the rear sun gear.
• The 3rd one-way clutch regulates reverse rotation of the front sun gear.
• During deceleration, the mid sun gear turns forward, so the forward one-way clutch idles and the engine
brake is not activated.
1. Front brake 2. Input clutch3. 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 gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
PCIA0003J
Revision: April 20092010 QX56

A/T CONTROL SYSTEMTM-13
< FUNCTION DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
“1” Position 1GR
• 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 clutch3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1512E
Revision: April 20092010 QX56

TM-14
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
“D”, “4”, “3” Positions 2GR
• 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 clutch3. 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 gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1513E
Revision: April 20092010 QX56

A/T CONTROL SYSTEMTM-15
< FUNCTION DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
“2”, “1” Positions 2GR
• 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 clutch3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1514E
Revision: April 20092010 QX56

TM-20
< FUNCTION DIAGNOSIS >
A/T CONTROL SYSTEM
TCM Function
INFOID:0000000005148510
The function of the TCM is to:
• Receive input signals sent from various switches and sensors.
• Determine required line pressure, shifting poi nt, 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 vari ous sensors or signals. It always
controls the optimum shift position and reduces shifting and lock-up shocks.
1. Front brake 2. Input clutch3. 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 gear12. Input shaft
13. Mid internal gear 14. Front internal gear15. Rear carrier
16. Rear sun gear 17. Mid sun gear18. Front carrier
19. Mid carrier 20. Rear internal gear21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1519E
Revision: April 20092010 QX56

A/T CONTROL SYSTEMTM-21
< FUNCTION DIAGNOSIS >
CEF
G H
I
J
K L
M A
B
TM
N
O P
CONTROL SYSTEM DIAGRAM
CAN CommunicationINFOID:0000000005148511
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-4,
"System Description".
SENSORS (or SIGNALS)
⇒TCM
⇒ACTUATORS
Transmission range switch
Accelerator pedal position sensor
Closed throttle position signal
Wide open throttle position signal
Engine speed signal
A/T fluid temperature sensor
Output speed sensor
Vehicle speed signal
Stop lamp switch signal
Input speed sensor
1st position switch signal
4th position switch signal
ATF pressure switch 2 signal
Tow mode switch signal Shift control
Line pressure control
Lock-up control
Engine brake control
Timing control
Fail-safe control
Self-diagnosis
CONSULT-III co
mmunication
line
Duet-EA control
CAN system Input clutch solenoid valve
Direct clutch solenoid valve
Front brake solenoid valve
High and low reverse clutch sole-
noid 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
JSDIA1315GB
Revision: April 20092010 QX56