2010 INFINITI QX56 check transmission fluid

DLN-14
< FUNCTION DIAGNOSIS >[ATX14B]
4WD SYSTEM
• Displays 4LO condition while engine is running. 4LO indicator lamp flashes if transfer gear does not shift
completely under 2WD, AUTO, 4H ⇔4LO. (When 4WD warning lamp is turned on, 4LO indicator lamp is
turned off.)
• Turns ON for approximately 1 second when ignition switch is turned ON, for purpose of lamp check.
4WD WARNING LAMP
Turns on or flashes when there is a malfunction in 4WD system.
Also turns on when ignition switch is turned ON, for purpose of lamp che\
ck. Turns OFF approximately 1 sec-
ond after the engine starts if system is normal.
4WD Warning Lamp Indication
ATP WARNING LAMP
When the A/T selector lever is in P position, the vehicle may move if the transfer case is in neutral. ATP warn-
ing lamp is turned on to indicate this condition to the driver.
LINE PRESSURE SWITCH
• With the transfer system design, control of the oil pressure provides the transmission of drive torque to the
front wheels. The main pressure to control the oil pressure is referred to as the line pressure.
• The line pressure switch determines whether or not adequate line pressure has built up under different oper- ating conditions.
• The line pressure switch closes when line pressure is produced.
• The line pressure switch senses line pressure abnormalities and turns the 4WD warning lamp ON.
CLUTCH PRESSURE SWITCH
• The clutch pressure switch determines whether or not adequate clutch pressure has built up under different
operating conditions.
• The clutch pressure switch closes when clutch pressure is produced.
• The clutch pressure switch senses clutch pressure abnormalities and turns the 4WD warning lamp ON.
WAIT DETECTION SWITCH
• The wait detection switch operates when there is circulating torque produced in the propeller shaft (L→H) or
when there is a phase difference between 2-4 sleeve and clutch drum (H →L). After the release of the circu-
lating torque, the wait detection switch helps provi de the 4WD lock gear (clutch drum) shifts. A difference
may occur between the operation of the 4WD shift swit ch and actual drive mode. At this point, the wait
detection switch senses an actual drive mode.
• The wait detection switch operates as follows.
- 4WD lock gear (clutch drum) locked: ON
- 4WD lock gear (clutch drum) released: OFF
• The wait detection switch senses an actual drive mode and the 4WD shift indicator lamp indicates the vehi-
cle drive mode.
ATP SWITCH
ATP switch detects if transfer case is in neutral by the position of the L-H shift fork.
NOTE:
Transfer case may be in neutral when shifting between 4H-4LO.
NEUTRAL-4LO SWITCH
The neutral-4LO switch detects that transfer gear is in neutral or 4LO (or shifting from neutral to 4LO) condi-
tion by L-H shift fork position.
Condition 4WD warning lamp
System normal OFF
Lamp check Turns ON when ignition switch is turned ON.
Turns OFF after engine start.
4WD system malfunction ON
During self-diagnosis Flashes malfunction mode.
Large difference in diameter of front/
rear tires Flashes slow (1 flash / 2 seconds)
(Continues to flash until the ignition switch is turned OFF)
High fluid temperature in transfer case Flashes rapidly (2 flashes / 1 second)
(Continues to flash until fluid temperature returns to normal)
Revision: April 20092010 QX56

TRANSFER CONTROL UNITDLN-99
< ECU DIAGNOSIS > [ATX14B]
C
EF
G H
I
J
K L
M A
B
DLN
N
O P
CAUTION:
• If CAN COMM CIRCUIT [U1000] or CONTROL UNIT (CAN) [U1010] is displayed with other DTCs, first perform the trouble
diagnosis for CAN communication line.
• If ABS OP SIG [P1830], VDC OP SIG [P1831] or TCS OP SIG [P 1832] is displayed, first perform the trouble diagnosis for ABS
system.
• If VHCL SPEED SEN·AT [P1807] is displayed, firs t perform the trouble diagnosis for A/T system.
NOTE:
• If SHIFT ACT POSI SW [P1818] or SHIFT ACT CIR [P1819] is disp layed, first erase self-diagnostic results. (SHIFT ACT POSI SW
[P1818] or SHIFT ACT CIR [P1819] may be displayed after installing transfer control unit or transfer assembly.)
• If CL PRES SW [P1827] or LINE PRES SW [P1828] is displayed only while driving in reverse, check the continuity of R position o n
transmission range switch. When there is no malfunction found in the electrical system, check the hydraulic system.
FLASH CODE CHART
[P1826] OIL TEMP SEN Signal voltage from transfer fluid temperature sen-
sor is abnormally high (Transfer fluid temperature is
abnormally low) while driving. Refer to
DLN-68.
[P1827] CLUTCH PRES SW • Improper signal from clutch pressure switch is in-
put due to open or short circuit.
• Malfunction occurs in clutch pressure switch or
hydraulic circuit. Refer to
DLN-71
.
[P1828] LINE PRES SW • Improper signal from line pressure switch is input
due to open or short circuit.
• Malfunction occurs in line pressure switch or hy-
draulic circuit. Refer to
DLN-74
.
[P1829] THROTTLE POSI SEN • Malfunction is detected in accelerator pedal posi-
tion signal that is output from ECM through CAN
communication.
• Signal voltage from accelerator pedal position sensor is abnormally high or low. Refer to
DLN-77
.
[P1830] ABS OP SIG Malfunction is detected in ABS operation signal that
is output from ABS actuator and electric unit (control
unit) through CAN communication. Refer to
DLN-78
.
[P1831] VDC OP SIG Malfunction is detected in VDC operation signal that
is output from ABS actuator and electric unit (control
unit) through CAN communication.
Refer to
DLN-79
.
[P1832] TCS OP SIG Malfunction is detected in TCS operation signal that
is output from ABS actuator and electric unit (control
unit) through CAN communication. Refer to
DLN-80
.
DTC CONSULT-III Diagnostic item is detected when... Reference
Flashing pattern
ItemDiagnostic item is detected when... Reference
2 Vehicle speed signal
(from A/T) • Malfunction is detected in output shaft revolution signal
that is output from TCM through CAN communication.
• Improper signal is input while driving. Refer to DLN-27
.
3 Clutch pressure sole-
noid signal Proper voltage is not applied to clutch pressure solenoid
valve due to open or short circuit.
Refer to DLN-54
.
4 2-4WD solenoid signal Proper voltage is not applied to 2-4WD solenoid valve due
to open or short circuit. Refer to DLN-58
.
5 Transfer motor Transfer motor does not operate properly due to open or
short circuit in transfer motor or transfer motor relay.
Refer to DLN-62
.
6 Vehicle speed signal
(from ABS) • Malfunction is detected in vehicle speed signal that is out-
put from ABS actuator and electric unit (control unit)
through CAN communication.
• Improper signal is input while driving. Refer to DLN-28
.
7 CAN communication Malfunction has been detected from CAN communication
line. Refer to LAN-14
.
8 AD converter AD converter system of transfer control unit is malfunction-
ing. Refer to DLN-25
.
Revision: April 20092010 QX56

EM-52
< ON-VEHICLE REPAIR >
TIMING CHAIN
b. Select the one most visible notch of the four on the bolt flange.Corresponding to the selected notch, put a alignment mark
(such as paint) on the crankshaft pulley.
14. Rotate the crankshaft pulley in normal direction (clockwise when viewed from engine front) to check for parts interference.
15. Installation of the remaining components is in the reverse of order of removal.
INSPECTION AFTER INSTALLATION
• Before starting the engine, check oil/fluid levels in cluding engine coolant and engine oil. If the levels are
lower than required quantity, fill to the specified level. Refer to MA-13, "
Fluids and Lubricants".
• Use procedure below to check for fuel leakage.
• Turn ignition switch ON (with engine stopped). With fuel pressure applied to the fuel piping, check for fuel leakage at the connection points.
• Start engine. With engine speed increased, che ck again for fuel leakage at connection points.
• Run engine to check for unusual noise and vibration. NOTE:
If hydraulic pressure inside timing chain tensioner drops after removal and installation, slack in the guide
may generate a pounding noise during and just after engine start. However, this is normal. Noise will stop
after hydraulic pressure rises.
• Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids including engine oil and engine coolant.
• Bleed air from passages in lines and hoses, such as in cooling system.
• After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. Refill to
specified level if necessary.
• Summary of the inspection items:
*Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.
Crankshaft pulley bolt torque
Step 1 : 93.1 N·m (9.5 kg-m, 69 ft-lb)
Step 2 : additional 90 ° (angle tightening)
KBIA2519E
Item Before starting engine Engine runningAfter engine stopped
Engine coolant LevelLeakage Level
Engine oil LevelLeakage Level
Other oils and fluids* LevelLeakage Level
Fuel LeakageLeakageLeakage
Exhaust gas —Leakage —
Revision: April 20092010 QX56

EM-70
< ON-VEHICLE REPAIR >
CYLINDER HEAD
• After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. Refill tospecified level if necessary.
• Summary of the inspection items:
*Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.
Exploded ViewINFOID:0000000005149009
Disassembly and AssemblyINFOID:0000000005149010
DISASSEMBLY
1. Remove the spark plug. Refer to EM-16, "Removal and Installation".
2. Remove the valve lifter. • Identify the installation positions, and store them without mixing them up.
Item Before starting engine Engine runningAfter engine stopped
Engine coolant LevelLeakage Level
Engine oil LevelLeakage Level
Other oils and fluids* LevelLeakage Level
Fuel LeakageLeakageLeakage
Exhaust gas —Leakage —
1. Spark plug 2. Valve lifter3. Valve collet
4. Valve spring retainer 5. Valve spring6. Valve spring seat
7. Valve oil seal 8. Valve guide9. Valve seat
10. Valve (INT) 11. Valve (EXH)12. Cylinder head (LH bank)
13. Spark plug tube 14. Cylinder head (RH bank)
WBIA0470E
Revision: April 20092010 QX56

ENGINE ASSEMBLYEM-81
< REMOVAL AND INSTALLATION >
C
DE
F
G H
I
J
K L
M A
EM
NP
O
• Tighten engine mounting bracket bolts in numerical order as
shown.
CAUTION:
• When replacing an engine or tr ansmission you must make sure the dowels are installed correctly
during re-assembly.
• Improper alignment caused by missing dowels m ay cause vibration, oil leaks or breakage of driv-
etrain components.
INSPECTION AFTER INSTALLATION
• Before starting the engine, check oil/fluid levels including engine coolant and engine oil. If the levels are
lower than required quantity, fill to the specified level. Refer to MA-13, "
Fluids and Lubricants".
• Use procedure below to check for fuel leakage.
• Turn ignition switch ON (with engine stopped). With fuel pressure applied to the fuel piping, check for fuel leakage at the connection points.
• Start engine. With engine speed increased, check again for fuel leakage at connection points.
• Run engine to check for unusual noise and vibration. NOTE:
If hydraulic pressure inside timing chain tensioner drops after removal and installation, slack in the guide
may generate a pounding noise during and just after engine start. However, this is normal. Noise will stop
after hydraulic pressure rises.
• Warm up engine thoroughly to make sure there is no leakage of fuel, exhaust gas, or any oils/fluids including engine oil and engine coolant.
• Bleed air from passages in lines and hoses, such as in cooling system.
• After cooling down the engine, again check oil/fluid levels including engine oil and engine coolant. Refill to
specified level if necessary.
• Summary of the inspection items:
*Transmission/transaxle/CVT fluid, power steering fluid, brake fluid, etc.
Engine mounting bracket
bolts : 49 N·m (5.0 kg-m, 36 ft-lb)
AWBIA0820ZZ
Item
Before starting engine Engine runningAfter engine stopped
Engine coolant LevelLeakage Level
Engine oil LevelLeakage Level
Other oils and fluids* LevelLeakage Level
Fuel LeakageLeakage Leakage
Exhaust gas —Leakage —
Revision: April 20092010 QX56

GI-26
< PRECAUTION >
PRECAUTIONS
• Before starting repairs which do not require battery power:Turn off ignition switch.
Disconnect the negative battery terminal.
• If the battery terminals are disconnected, recorded memory of radio and each control unit is erased.
• To prevent serious burns: Avoid contact with hot metal parts.
Do not remove the radiator cap when the engine is hot.
• Dispose of drained oil or the solvent used for cleaning parts in an appropriate manner.
• Do not attempt to top off the fuel tank after the fuel pump nozzle
shuts off automatically.
Continued refueling may cause fuel overflow, resulting in fuel spray
and possibly a fire.
• Clean all disassembled parts in the designated liquid or solvent prior to inspection or assembly.
• Replace oil seals, gaskets, packings, O-rings, locking washers,
cotter pins, self-locking nuts, etc. with new ones.
• Replace inner and outer races of tapered roller bearings and needle bearings as a set.
• Arrange the disassembled parts in accordance with their assembled locations and sequence.
• Do not touch the terminals of electrical com ponents which use microcomputers (such as ECM).
Static electricity may damage internal electronic components.
• After disconnecting vacuum or air hoses, atta ch a tag to indicate the proper connection.
• Use only the fluids and lubricants specified in this manual.
• Use approved bonding agent, sealants or their equivalents when required.
• Use hand tools, power tools (disassembly only) and recommended special tools where specified for safe and efficient service repairs.
• When repairing the fuel, oil, water, vacuum or exhaust systems, check all affected lines for leaks.
• Before servicing the vehicle: Protect fenders, upholstery and carpeting with appropriate covers.
Take caution that keys, buckles or buttons do not scratch paint.
WARNING:
To prevent ECM from storing the diagnostic tro uble codes, do not carelessly disconnect the harness
connectors which are related to the engine control system and TCM (transmission control module)
SEF289H
SGI233
PBIC0190E
SGI234
Revision: April 20092010 QX56

CHASSIS AND BODY MAINTENANCEMA-27
< ON-VEHICLE MAINTENANCE >
C
DE
F
G H
I
J
K L
M B
MA
N
O A
• If anything is found, repair or replace damaged parts.
A/T FLUID
A/T FLUID : Checking
the A/T Fluid (ATF)INFOID:0000000005403151
CAUTION:
If using the vehicle for towing, the A/T fluid must be replaced as specified. Refer to MA-9, "
Introduc-
tion of Periodic Maintenance".
1. Before driving, the A/T fluid level can be checked at A/T fluid temperatures of 30 ° to 50 ° C (86 ° to 122° F) using the “COLD”
range on the A/T fluid 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 A/T fluid level with the engine idling.
d. Remove the A/T fluid level gauge and wipe it clean with a lint- free paper.
CAUTION:
When wiping the A/T fluid from the A/T fluid level gauge,
always use a lint-free paper, not a cloth.
e. Re-insert the A/T fluid level gauge into the A/T fluid charging pipe until the cap contacts the top of the A/T fluid charging pipe
as shown.
CAUTION:
To check A/T fluid level, insert th e A/T fluid level gauge until
the cap contacts the top of the A/T fluid charging pipe, with
the gauge reversed from the normal inserted position.
f. Remove the A/T fluid level gauge and note the A/T fluid level. If the A/T fluid level is at low side of range, add A/T fluid to the
transmission through the A/T fluid charging pipe.
CAUTION:
Do not overfill the tran smission with A/T fluid.
g. Install the A/T fluid level gauge and the A/T fluid level gauge bolt.
2. Warm up the engine and transmission.
3. Check for any A/T fluid leaks.
4. Drive the vehicle to increase the A/T fluid temperature to 80 ° C (176 ° F).
SMA211A
LLIA0071E
A/T fluid level
gauge bolt : Refer to
TM-186, "Removal and Installation (2WD)" or TM-188, "Removal
and Installation (4WD)"
SCIA2899E
Revision: April 20092010 QX56

MA-28
< ON-VEHICLE MAINTENANCE >
CHASSIS AND BODY MAINTENANCE
5. Allow the A/T fluid temperature to fall to approximately 65°C (149°F). Use the CONSULT-III to monitor the
A/T fluid temperature as follows:
NOTE:
The A/T fluid level will be significantly affected by t he A/T fluid temperature as shown. Therefore monitor
the A/T fluid temperature data using the CONSULT-III.
a. Connect CONSULT-III to data link connector.
b. Select “MAIN SIGNALS” in “DATA MONI TOR” mode for “A/T” with CONSULT-III.
c. Read out the value of “ATF TEMP 1”.
6. Re-check the A/T fluid level at A/T fluid temperatures of approxi- mately 65 °C (149° F) using the “HOT” range on the A/T fluid
level gauge as shown. The HOT range is between 50 ° - 80 ° C
(122° - 176 ° F).
CAUTION:
• When wiping the A/T fluid from the A/T fluid level gauge,
always use lint-free paper, not a cloth.
• To check the A/T fluid level , insert the A/T fluid level
gauge until the cap contacts the top of the A/T fluid charg-
ing pipe, with the gauge reversed from the normal
inserted position as shown.
7. Check the A/T fluid condition. • If the A/T fluid is very dark or has some burned smell, there
may be an internal problem with the transmission. Refer to
TM-152, "
A/T Fluid Cooler Cleaning". Flush the transmission
cooling system after repairing the transmission.
• If the A/T fluid contains frictional material (clutches, bands, etc.), replace the radiator and flush the transmission cooler
lines using cleaning solvent and compressed air after repairing
the transmission.
8. Install the A/T fluid level gauge in the A/T fluid charging pipe.
9. Tighten the A/T fluid level gauge bolt to specification.
SLIA0016E
LLIA0071E
A/T fluid level
gauge bolt : Refer to
TM-186, "Removal and Installation (2WD)" or TM-188, "Removal
and Installation (4WD)"
SCIA2899E
Revision: April 20092010 QX56