2007 INFINITI QX56 check transmission fluid

AT-1
TRANSMISSION/TRANSAXLE
D
E
F
G
H
I
J
K
L
M
SECTION AT
A
B
AT
N
O
P
CONTENTS
AUTOMATIC TRANSMISSION
SERVICE INFORMATION ............................6
INDEX FOR DTC .................................................6
Alphabetical Index .....................................................6
DTC No. Index ..........................................................6
PRECAUTIONS ...................................................8
Precaution for Supplemental Restraint System
(SRS) "AIR BAG" and "SEAT BELT PRE-TEN-
SIONER" ...................................................................
8
Precaution for On Board Diagnosis (OBD) System
of A/T and Engine .....................................................
8
Precaution .................................................................8
Service Notice or Precaution .....................................9
PREPARATION ..................................................11
Special Service Tool ...............................................11
Commercial Service Tool ........................................12
A/T FLUID ...........................................................13
Changing Automatic Transmission Fluid (ATF) ......13
Checking Automatic Transmission Fluid (ATF) .......13
A/T Fluid Cooler Cleaning .......................................15
A/T CONTROL SYSTEM ....................................19
Cross-Sectional View (2WD models) ......................19
Cross-Sectional View (4WD models) ......................20
Shift Mechanism ......................................................20
TCM Function ..........................................................31
CAN Communication ...............................................32
Input/Output Signal of TCM .....................................33
Line Pressure Control .............................................33
Shift Control ............................................................35
Lock-up Control .......................................................36
Engine Brake Control ..............................................37
Control Valve ...........................................................37
ON BOARD DIAGNOSTIC (OBD) SYSTEM ......39
Introduction .............................................................39
OBD-II Function for A/T System ..............................39
One or Two Trip Detection Logic of OBD-II ............39
OBD-II Diagnostic Trouble Code (DTC) ..................39
Malfunction Indicator Lamp (MIL) ............................41
TROUBLE DIAGNOSIS ....................................43
DTC Inspection Priority Chart ..................................43
Fail-Safe ..................................................................43
How To Perform Trouble Diagnosis for Quick and
Accurate Repair .......................................................
44
A/T Electrical Parts Location ...................................50
Circuit Diagram ........................................................51
Inspections Before Trouble Diagnosis .....................51
Check Before Engine Is Started ..............................55
Check at Idle ............................................................55
Cruise Test - Part 1 .................................................56
Cruise Test - Part 2 .................................................58
Cruise Test - Part 3 .................................................59
Vehicle Speed When Shifting Gears .......................59
Vehicle Speed When Performing and Releasing
Complete Lock-up ...................................................
60
Vehicle Speed When Performing and Releasing
Slip Lock-up .............................................................
60
Symptom Chart ........................................................60
TCM Input/Output Signal Reference Value .............82
CONSULT-II Function (A/T) ....................................83
DTC U1000 CAN COMMUNICATION LINE .....91
Description ...............................................................91
On Board Diagnosis Logic .......................................91
Possible Cause ........................................................91
DTC Confirmation Procedure ..................................91
Wiring Diagram - AT - CAN .....................................92
Diagnosis Procedure ...............................................93
DTC P0615 START SIGNAL CIRCUIT .............94
Description ...............................................................94
CONSULT-II Reference Value in Data Monitor
Mode ........................................................................
94
On Board Diagnosis Logic .......................................94
Possible Cause ........................................................94
DTC Confirmation Procedure ..................................94
Wiring Diagram - AT - STSIG ..................................95
Diagnosis Procedure ...............................................95

AT-4
DTC Confirmation Procedure ................................152
Diagnosis Procedure .............................................152
DTC P1845 ATF PRESSURE SWITCH 5 ........154
Description .............................................................154
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
154
On Board Diagnosis Logic .....................................154
Possible Cause ......................................................154
DTC Confirmation Procedure ................................154
Diagnosis Procedure .............................................154
DTC P1846 ATF PRESSURE SWITCH 6 ........156
Description .............................................................156
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
156
On Board Diagnosis Logic .....................................156
Possible Cause ......................................................156
DTC Confirmation Procedure ................................156
Diagnosis Procedure .............................................156
MAIN POWER SUPPLY AND GROUND CIR-
CUIT .................................................................
158
Wiring Diagram - AT - MAIN ..................................158
Diagnosis Procedure .............................................159
CLOSED THROTTLE POSITION AND WIDE
OPEN THROTTLE POSITION CIRCUIT .........
161
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
161
Diagnosis Procedure .............................................161
BRAKE SIGNAL CIRCUIT ..............................162
CONSULT-II Reference Value in Data Monitor
Mode ......................................................................
162
Diagnosis Procedure .............................................162
TOW MODE SWITCH ......................................163
Description .............................................................163
Wiring Diagram - AT - TMSW ................................163
Diagnosis Procedure .............................................164
TROUBLE DIAGNOSIS FOR SYMPTOMS .....165
Wiring Diagram - AT - NONDTC ............................165
A/T Check Indicator Lamp Does Not Come On .....167
Engine Cannot Be Started in "P" or "N" Position ...168
In "P" Position, Vehicle Moves When Pushed .......168
In "N" Position, Vehicle Moves ..............................169
Large Shock ("N" to "D" Position) ..........................170
Vehicle Does Not Creep Backward in "R" Position ..172
Vehicle Does Not Creep Forward in "D" Position ..175
Vehicle Cannot Be Started from D1 .......................177
A/T Does Not Shift: D1→ D2 ..................................179
A/T Does Not Shift: D2→ D3 ..................................181
A/T Does Not Shift: D3→ D4 ..................................183
A/T Does Not Shift: D4→ D5 ..................................185
A/T Does Not Perform Lock-up .............................187
A/T Does Not Hold Lock-up Condition ...................189
Lock-up Is Not Released .......................................190
Engine Speed Does Not Return to Idle .................191
A/T Does Not Shift: 5th gear → 4th gear ..............192
A/T Does Not Shift: 4th gear → 3rd gear ..............194
A/T Does Not Shift: 3rd gear → 2nd gear .............196
A/T Does Not Shift: 2nd gear → 1st gear .............197
Vehicle Does Not Decelerate By Engine Brake ....199
A/T SHIFT LOCK SYSTEM ..............................202
Description ............................................................202
Shift Lock System Electrical Parts Location ..........202
Wiring Diagram - AT - SHIFT ................................203
Shift Lock Control Unit Reference Value ..............204
Component Inspection ..........................................204
SHIFT CONTROL SYSTEM .............................207
Control Device Removal and Installation ..............207
Adjustment of A/T Position ....................................208
Checking of A/T Position .......................................208
ON-VEHICLE SERVICE ...................................209
Oil Pan ..................................................................209
Control Valve with TCM and A/T Fluid Tempera-
ture Sensor 2 ........................................................
210
Rear Oil Seal .........................................................219
AIR BREATHER HOSE ....................................221
Removal and Installation .......................................221
TRANSMISSION ASSEMBLY ..........................223
Removal and Installation (2WD) ...........................223
Removal and Installation (4WD) ...........................225
OVERHAUL ......................................................228
Component ...........................................................228
Oil Channel ...........................................................235
Location of Adjusting Shims, Needle Bearings,
Thrust Washers and Snap Rings ..........................
237
DISASSEMBLY ................................................240
Disassembly ..........................................................240
REPAIR FOR COMPONENT PARTS ..............258
Oil Pump ...............................................................258
Front Sun Gear, 3rd One-Way Clutch ...................260
Front Carrier, Input Clutch, Rear Internal Gear .....262
Mid Sun Gear, Rear Sun Gear, High and Low Re-
verse Clutch Hub ..................................................
267
High and Low Reverse Clutch ..............................272
Direct Clutch .........................................................274
ASSEMBLY ......................................................277
Assembly (1) .........................................................277
Adjustment ............................................................290
Assembly (2) .........................................................292
SERVICE DATA AND SPECIFICATIONS
(SDS) ................................................................
298
General Specification ............................................298
Vehicle Speed When Shifting Gears .....................298
Vehicle Speed When Performing and Releasing
Complete Lock-up .................................................
299
Stall Speed ............................................................299

PRECAUTIONS
AT-9
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
•After performing each TROUBLE DIAGNOSIS, perform “DTC
(Diagnostic Trouble Code) CONFIRMATION PROCEDURE”.
If the repair is completed the DTC should not be displayed in
the “DTC CONFIRMATION PROCEDURE”.
• Always use the specified brand of ATF. Refer to MA-10
.
• Use paper rags not cloth rags during work.
• After replacing the ATF, dispose of the waste oil using the methods prescribed by law, ordinance, etc.
• Before proceeding with disassembly, thoroughly clean the outside of the transmission. It is important to pre-
vent the internal parts from becoming contaminated by dirt or other foreign matter.
• Disassembly should be done in a clean work area.
• Use lint-free cloth or towels for wiping parts clean. Common shop rags can leave fibers that could interfere
with the operation of the transmission.
• Place disassembled parts in order for easier and proper assembly.
• All parts should be carefully cleaned with a general purpose, non-flammable solvent before inspection or
reassembly.
• Gaskets, seals and O-rings should be replaced any time the transmission is disassembled.
• It is very important to perform functional tests whenever they are indicated.
• The valve body contains precision parts and requires extreme care when parts are removed and serviced.
Place disassembled valve body parts in order for easier and proper assembly. Care will also prevent springs
and small parts from becoming scattered or lost.
• Properly installed valves, sleeves, plugs, etc. will slide along bores in valve body under their own weight.
• Before assembly, apply a coat of recommended ATF to all parts. Apply petroleum jelly to protect O-rings and
seals, or hold bearings and washers in place during assembly. Do not use grease.
• Extreme care should be taken to avoid damage to O-rings, seals and gaskets when assembling.
• Clean or replace ATF cooler if excessive foreign material is found in oil pan or clogging strainer. Refer to AT-
15, "A/T Fluid Cooler Cleaning".
• After overhaul, refill the transmission with new ATF.
• When the A/T drain plug is removed, only some of the fluid is drained. Old A/T fluid will remain in torque con-
verter and ATF cooling system.
Always follow the procedures under “Changing A/T Fluid” in the AT section when changing A/T fluid. Refer to
AT-13, "
Changing Automatic Transmission Fluid (ATF)", AT-13, "Checking Automatic Transmission Fluid
(ATF)".
Service Notice or PrecautionINFOID:0000000003532221
ATF COOLER SERVICE
If A/T fluid contains frictional material (clutches, bands, etc.), or if an A/T is repaired, overhauled, or replaced,
inspect and clean the A/T fluid cooler mounted in the radiator or replace the radiator. Flush cooler lines using
cleaning solvent and compressed air after repair. For A/T fluid cooler cleaning procedure, refer to AT-15, "
A/T
Fluid Cooler Cleaning". For radiator replacement, refer to CO-13.
CHECKING AND CHANGING A/T FLUID SERVICE
Increase ATF temperature by 80°C (176°F) once, and then check ATF level in 65°C (149°F) when adjusting
ATF level.
NOTE:
JA60 uses both systems of a water-cooling and of an air-cooling. Air-cooling system has a by-pass valve.
When ATF temperature is not over 50°C (122°F) with water-cooling system OFF, it does not flow to air-cooling
system. If ATF level is set without the flow of ATF, the level will be 10mm lower than the standard. Therefore,
piping should be filled with ATF when adjusting level.
OBD-II SELF-DIAGNOSIS
• A/T self-diagnosis is performed by the TCM in combination with the ECM. Refer to the table on AT-83,
"CONSULT-II Function (A/T)" for the indicator used to display each self-diagnostic result.
SEF217U

A/T FLUID
AT-13
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
A/T FLUID
Changing Automatic Transmission Fluid (ATF)INFOID:0000000003532224
1. Drive the vehicle to warm up the ATF to 80° C (176° F).
2. Stop the engine.
3. Remove the ATF level gauge bolt.
4. Drain the ATF from the drain plug hole and then install the drain
plug with a new gasket. Refill the transmission with new ATF.
Always refill with the same volume as the drained ATF. Use the
ATF level gauge to check the ATF level as shown. Add ATF as
necessary.
• To flush out the old ATF from the coolers, pour new ATF into the charging pipe with the engine idling and
at the same time drain the old ATF from the auxiliary transmission oil cooler hose return line.
• When the color of the ATF coming out of the auxiliary transmission oil cooler hose return line is about
the same as the color of the new ATF, flushing out the old ATF is complete. The amount of new trans-
mission ATF used for flushing should be 30% to 50% increase of the specified capacity.
CAUTION:
• Use only the specified ATF. Do not mix with other fluids.
• Using an ATF other than the specified ATF will cause deterioration in driveability and automatic
transmission durability, and may damage the automatic transmission, which is not covered by
the warranty.
• When filling the transmission with ATF, do not spill the ATF on any heat generating parts such as
the exhaust manifold.
• Do not reuse the drain plug gasket.
5. Install the ATF level gauge in the ATF charging pipe and tighten the ATF level gauge bolt to specification.
6. Drive the vehicle to warm up the ATF to 80° C (176° F).
7. Check the ATF level and condition. Refer to AT-13, "
Checking Automatic Transmission Fluid (ATF)". If the
ATF is still dirty, repeat steps 2 through 5.
Checking Automatic Transmission Fluid (ATF)INFOID:0000000003532225
1. Remove the ATF level gauge bolt.Drain plug : Refer to AT-228, "
Component".
WLIA0014E
ATF type and capacity : Refer to MA-10, "Fluids and Lubricants".
Drain plug : Refer to AT-228, "
Component".
ATF level gauge bolt : Refer to AT-223, "
Removal and Installation (2WD)",
AT-225, "
Removal and Installation (4WD)".

AT-14
< SERVICE INFORMATION >
A/T FLUID
2. Before driving, the ATF level can be checked at ATF tempera-
tures of 30° to 50°C (86° to 122°F) using the “COLD” range on
the ATF level gauge as follows:
a. Park the vehicle on a level surface and set the parking brake.
b. Start the engine and move the selector lever through each gear
position. Shift the selector lever into the “P” position.
c. Check the ATF level with the engine idling.
d. Remove the ATF level gauge and wipe it clean with a lint-free
paper.
CAUTION:
When wiping the ATF from the ATF level gauge, always use
a lint-free paper, not a cloth.
e. Re-insert the ATF level gauge into the charging pipe until the
cap contacts the top of the charging pipe as shown.
CAUTION:
To check ATF level, insert the ATF level gauge until the cap
contacts the top of the charging pipe, with the gauge
reversed from the normal inserted position.
f. Remove the ATF level gauge and note the ATF level. If the ATF
level is at low side of range, add ATF to the transmission
through the charging pipe.
CAUTION:
Do not overfill the transmission with ATF.
g. Install the ATF level gauge and the ATF level gauge bolt.
3. Warm up the engine.
4. Check for any ATF leaks.
5. Drive the vehicle to increase the ATF temperature to 80° C (176° F).
6. Allow the ATF temperature to fall to approximately 65°C (149°F). Use the CONSULT-II to monitor the ATF
temperature as follows:
NOTE:
ATF level will be greatly affected by temperature as shown. Therefore monitor the ATF temperature data
using the CONSULT-II.
a. Connect CONSULT-II to data link connector.
b. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T” with CONSULT-II.
c. Read out the value of “ATF TEMP 1”.
WLIA0014E
ATF level gauge bolt : Refer to AT-223, "Removal and Installation (2WD)",
AT-225, "
Removal and Installation (4WD)".
SCIA1684E
SLIA0016E

A/T FLUID
AT-15
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
7. Re-check the ATF level at ATF temperatures of approximately
65°C (149°F) using the “HOT” range on the ATF level gauge as
shown.
CAUTION:
• When wiping the ATF from the ATF level gauge, always
use lint-free paper, not a cloth.
• To check the ATF level, insert the ATF level gauge until the
cap contacts the top of the charging pipe, with the gauge
reversed from the normal inserted position as shown.
8. Check the ATF condition.
• If the ATF is very dark or has some burned smell, there may be an internal problem with the transmis-
sion. Refer to AT-165
. Flush the transmission cooling system after repairing the transmission.
• If the ATF contains frictional material (clutches, bands, etc.), replace the radiator and flush the transmis-
sion cooler lines using cleaning solvent and compressed air after repairing the transmission.
9. Install the ATF level gauge in the ATF charging pipe and install the ATF level gauge bolt.
10. Tighten the level gauge bolt to specification.
A/T Fluid Cooler CleaningINFOID:0000000003532226
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.
WLIA0014E
SCIA1684E
ATF level gauge
bolt:: Refer to AT-223, "Removal and Installation (2WD)",
AT-225, "
Removal and Installation (4WD)".

AT-32
< SERVICE INFORMATION >
A/T CONTROL SYSTEM
CONTROL SYSTEM DIAGRAM
CAN CommunicationINFOID:0000000003532231
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,
"CAN Communication System".
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 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
SCIA5624E

TROUBLE DIAGNOSIS
AT-51
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
Circuit DiagramINFOID:0000000003532247
Inspections Before Trouble DiagnosisINFOID:0000000003532248
A/T FLUID CHECK
Fluid Leakage and Fluid Level Check
• Inspect for fluid leakage and check the fluid level. Refer to AT-13, "Changing Automatic Transmission Fluid
(ATF)".
BCWA0496E