2007 INFINITI QX56 check engine

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

A/T FLUID
AT-13
< SERVICE INFORMATION >
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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

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

ON BOARD DIAGNOSTIC (OBD) SYSTEM
AT-39
< SERVICE INFORMATION >
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ON BOARD DIAGNOSTIC (OBD) SYSTEM
IntroductionINFOID:0000000003532238
The A/T system has two self-diagnostic systems.
The first is the emission-related on board diagnostic system (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MIL (malfunction indicator lamp) and is stored as a DTC in
the ECM memory but not the TCM memory.
The second is the TCM original self-diagnosis indicated by the A/T CHECK indicator lamp. The malfunction is
stored in the TCM memory. The detected items are overlapped with OBD-II self-diagnostic items. For detail,
refer to AT-83, "
CONSULT-II Function (A/T)".
OBD-II Function for A/T SystemINFOID:0000000003532239
The ECM provides emission-related on board diagnostic (OBD-II) functions for the A/T system. One function
is to receive a signal from the TCM used with OBD-related parts of the A/T system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-related part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indicator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to A/T system parts.
One or Two Trip Detection Logic of OBD-IIINFOID:0000000003532240
ONE TRIP DETECTION LOGIC
If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC
When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — 1st Trip
If the same malfunction as that experienced during the first test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd Trip
The “Trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC)INFOID:0000000003532241
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-II or GST) CONSULT-II or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)
•1st trip DTC No. is the same as DTC No.
•Output of the diagnostic trouble code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring or
occurred in the past and returned to normal.
CONSULT-II can identify them as shown below, therefore, CONSULT-II (if available) is recommended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown
on the next page. DTC or 1st trip DTC of a malfunction is displayed
in SELF-DIAGNOSTIC RESULTS mode for “ENGINE” with CON-
SULT-II. Time data indicates how many times the vehicle was driven
after the last detection of a DTC.
BCIA0030E

AT-42
< SERVICE INFORMATION >
ON BOARD DIAGNOSTIC (OBD) SYSTEM
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned “ON” with-
out the engine running. This is a bulb check.
• If the MIL does not light up, refer to DI-26
.
2. When the engine is started, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.
SEF217U

TROUBLE DIAGNOSIS
AT-45
< SERVICE INFORMATION >
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It is much more difficult to diagnose a error that occurs intermittently
rather than continuously. Most intermittent errors are caused by poor
electric connections or improper wiring. In this case, careful check-
ing of suspected circuits may help prevent the replacement of good
parts.
A visual check only may not find the cause of the errors. A road test
with CONSULT-II (or GST) or a circuit tester connected should be
performed. Follow the "WORK FLOW".
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” as shown on
the example (Refer to "Diagnostic Worksheet Chart") should be
used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
WORK FLOW
A good understanding of the malfunction conditions can make troubleshooting faster and more accurate.
In general, each customer feels differently about a malfunction. It is important to fully understand the symp-
toms or conditions for a customer complaint.
Make good use of the two sheets provided, “Information From Customer” (Refer to "Information From Cus-
tomer") and “Diagnostic Worksheet” (Refer to "Diagnostic Worksheet Chart"), to perform the best trouble-
shooting possible.
Work Flow Chart
SAT632I
SEF234G

AT-48
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
4o Perform all road tests and enter checks in required inspection items.AT- 5 1
4-1.Check before engine is started
AT- 5 5
o AT- 1 6 7 , "A/T Check Indicator Lamp Does Not Come On".
o Perform self-diagnostics Enter checks for detected items. AT- 8 3
o AT- 9 1
o AT- 9 4
o AT- 9 8
o AT- 9 9
o AT- 1 0 3
o AT- 1 0 5
o AT- 1 0 9
o AT- 111
o AT- 11 3
o AT- 11 5
o AT- 11 7
o AT- 11 9
o AT- 1 2 4
o AT- 1 2 6
o AT- 1 2 8
o AT- 1 3 0
o AT- 1 3 2
o AT- 1 3 4
o AT- 1 3 6
o AT- 1 3 8
o AT- 1 4 0
o AT- 1 4 2
o AT- 1 4 4
o AT- 1 4 6
o AT- 1 4 8
o AT- 1 5 0
o AT- 1 5 2
o AT- 1 5 4
o AT- 1 5 6
4-2.Idle inspection
AT- 5 5
o AT- 1 6 8 , "Engine Cannot Be Started in "P" or "N" Position"
o AT- 1 6 8 , "In "P" Position, Vehicle Moves When Pushed"
o AT- 1 6 9 , "In "N" Position, Vehicle Moves"
o AT- 1 7 0 , "Large Shock ("N" to "D" Position)"
o AT- 1 7 2 , "Vehicle Does Not Creep Backward in "R" Position"
o AT- 1 7 5 , "Vehicle Does Not Creep Forward in "D" Position"
4-3.Driving tests
AT- 5 6
Part 1
o AT- 1 7 7 , "
Vehicle Cannot Be Started from D1"
o AT- 1 7 9 , "A/T Does Not Shift: D1→ D2"
o AT- 1 8 1 , "A/T Does Not Shift: D2→ D3"
o AT- 1 8 3 , "A/T Does Not Shift: D3→ D4"
o AT- 1 8 5 , "A/T Does Not Shift: D4→ D5"
o AT- 1 8 7 , "A/T Does Not Perform Lock-up"
o AT- 1 8 9 , "A/T Does Not Hold Lock-up Condition"
o AT- 1 9 0 , "Lock-up Is Not Released"
o AT- 1 9 1 , "Engine Speed Does Not Return to Idle"