2011 INFINITI QX56 radiator

SQUEAK AND RATTLE TROUBLE DIAGNOSESEXT-9
< SYMPTOM DIAGNOSIS >
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1. Trunk lid dumpers out of adjustment
2. Trunk lid striker out of adjustment
3. Trunk lid torsion bars knocking together
4. A loose license plate or bracket
Most of these incidents can be repaired by adjusting, se curing, or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof / headlining area can of ten be traced to one of the following items:
1. Sunroof lid, rail, linkage, or seals making a rattle or light knocking noise
2. Sunvisor shaft shaking in the holder
3. Front or rear windshield touching headlining and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
SEATS
When isolating seat noise it is important to note the position the seat is in and the load placed on the seat
when the noise occurs. These conditions should be duplic ated when verifying and isolating the cause of the
noise.
Causes of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspected components while duplicating the con-
ditions under which the noise occurs. Most of thes e incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move, or insulate one component at a time and test drive the vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs c an usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: 2010 May2011 QX56

GI-28
< PRECAUTION >
PRECAUTIONS
 Before jacking up the vehicle, apply wheel chocks or other tireblocks to the wheels to prevent t he vehicle from moving. After jack-
ing up the vehicle, support the vehicle weight with safety stands at
the points designated for proper lifting before working on the vehi-
cle.
These operations should be done on a level surface.
 When removing a heavy component such as the engine or tran- saxle/transmission, be careful not to lose your balance and drop
them. Also, do not allow them to strike adjacent parts, especially
the brake tubes and master cylinder.
 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 leakage.
SGI231
SEF289H
SGI233
JPAIA0335ZZ
Revision: 2010 May2011 QX56

GW-8
< SYMPTOM DIAGNOSIS >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
3. The trunk lid torsion bars knocking together
4. A loose license plate or bracket
Most of these incidents can be repaired by adjusting, securing or insulatingthe item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof/headlining area c an often be traced to one of the following:
1. Sunroof lid, rail, linkage or seals making a rattle or light knockingnoise
2. Sunvisor shaft shaking in the holder
3. Front or rear windshield touching headlining and squeaking
Again, pressing on the components to stop the noise while duplicatingthe conditions can isolate most of these
incidents. Repairs usually consistof insulating with felt cloth tape.
SEATS
When isolating seat noise it's important to note the pos ition the seatis in and the load placed on the seat when
the noise is present. These conditionsshould be duplic ated when verifying and isolating the cause of the
noise.
Cause of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspectedcomponents while duplicating the condi-
tions under which the noise occurs. Most of these incidents can be repaired by repositioning the component
orapplying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or onthe engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move or insulate one component at a time and test drive the \
vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: 2010 May2011 QX56

REFRIGERATION SYSTEM SYMPTOMSHA-27
< SYMPTOM DIAGNOSIS >
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SYMPTOM DIAGNOSIS
REFRIGERATION SYSTEM SYMPTOMS
Trouble Diagnosis For Unusual PressureINFOID:0000000006276159
Diagnose using a manifold gauge whenever system’s high and/or low side pressure(s) is/are unusual. The
marker above the gauge scale in the following tables i ndicates the standard (usual) pressure range. Refer to
above table (Ambient air temperature-to-operating pre ssure table) since the standard (usual) pressure, how-
ever, differs from vehicle to vehicle.
Symptom TableINFOID:0000000006276160
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too high. The pressure returns to nor-
mal soon after sprinkling wa-
ter on condenser.
Overfilled refrigerant. Collect all refrigerant, evacuate
refrigerant cycle again, and
then refill it with the specified
amount of refrigerant.
Air flow to condenser is insuf-
ficient. Insufficient condenser cooling
performance.
 Poor fan rotation of radiator
and condenser.
 Improper installation of air guide.
 Clogged or dirty condenser fins.  Repair or replace malfunc-
tioning parts.
 Clean and repair condenser fins.
When compressor is stopped,
a high-pressure reading
quickly drops by approximate-
ly 196 kPa (2 kg/cm
2, 28 psi).
It then gradually decreases. Air mixed in refrigerant cycle.
Collect all refrigerant, evacuate
refrigerant cycle again, and
then refill it with the specified
amount of refrigerant.
 Low-pressure pipe is cooler than the outlet of evapora-
tor.
 Low-pressure pipe is frost- ed. Expansion valve opened too
much (excessive flow of refrig-
erant).
Replace expansion valve.
High-pressure side is excessively
high and low-pressure side is too
low. High-pressure pipe and upper
side of condenser become
hot, however, liquid tank does
not become so hot.Clogged or crushed high-pres-
sure pipe located between
compressor and condenser.
Repair or replace the malfunc-
tioning parts.
High-pressure side is too low and
low-pressure side is too high.  The readings of both sides
become equal soon after
compressor operation
stops.
 There is no temperature dif- ference between high- and
low-pressure sides. Malfunction in compressor sys-
tem (insufficient compressor
pressure operation).
 Damage or breakage of
valve.
 Malfunctioning gaskets. Replace compressor.
AC359A
AC360A
AC356A
Revision: 2010 May2011 QX56

HA-38
< REMOVAL AND INSTALLATION >
CONDENSER
CONDENSER
Exploded ViewINFOID:0000000006276178
CONDENSER
CONDENSER : Removal and InstallationINFOID:0000000006276179
CAUTION:
Perform lubricant return operation before each refrigeration system disassembly. However, if a large
amount of refrigerant or lubrican t is detected, never perform lubricant return operation. Refer to HA-
22, "Perform Lubricant Return Operation".
REMOVAL
1. Use a refrigerant collecting equipment (for HF C-134a) to discharge the refrigerant. Refer to HA-20, "Recy-
cle Refrigerant".
2. Remove the radiator core support upper. Refer to DLK-220, "
Removal and Installation".
3. Remove steering oil cooler. Refer to ST-54, "
Exploded View".
4. Remove A/T fluid cooler. Refer to TM-202, "
Removal and Installation".
5. Remove mounting bolt, and then disconnect high-pressure flexible hose from condenser. CAUTION:
Cap or wrap the joint of the A/C piping and conden ser with suitable material such as vinyl tape to
avoid the entry of air.
6. Remove mounting bolt, and then disconnect high-pressure pipe from condenser. CAUTION:
Cap or wrap the joint of the A/C piping and conden ser with suitable material such as vinyl tape to
avoid the entry of air.
7. Remove mounting bolts, and then remove condenser from the vehicle. CAUTION:
Be careful not to damage core surface of condenser.
INSTALLATION
Note the following items, and install in the reverse order of removal.
1. Outlet pipe assembly 2. Refrigerant pressure sensor 3. O-ring
4. Pipe cover 5. Liquid tank pipe 1 6. Liquid tank pipe 2
7. Liquid tank bracket 8. Liquid tank 9. Inlet pipe assembly
10. Condenser
Refer to GI-4, "
Components" for symbols in the figure.
JMIIA0627GB
Revision: 2010 May2011 QX56

A/C UNIT ASSEMBLYHA-43
< REMOVAL AND INSTALLATION >
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Perform lubricant return operati on before each refrigeration system disassembly. However, if a large
amount of refrigerant or lubricant is detected, n ever perform lubricant return operation. Refer to HA-
22, "Perform Lubricant Return Operation".
REMOVAL
1. Use a refrigerant collecting equipment (for HF C-134a) to discharge the refrigerant. Refer to HA-20, "Recy-
cle Refrigerant". (If equipped)
2. Drain engine coolant from cooling system. Refer to CO-8, "
Draining".
3. Remove clamps, and then disconnect front heater outlet hose from heater pipe.
CAUTION:
 Some coolant may spill when heater hoses are disconnected.
 Close off the coolant inlet and outlet on the heater core (2 locations) with shop cloths.
4. Remove mounting bolt, and then disconnect low-pressure pipe and high-pressure pipe from expansion valve.
CAUTION:
Cap or wrap the joint of the A/C piping and expan sion valve with suitable material such as vinyl
tape to avoid the entry of air.
5. Remove instrument panel assembly. Refer to IP-14, "
Removal and Installation".
6. Remove steering column mounting bolt and nuts. Refer to ST-34, "
Removal and Installation".
7. Move steering column assembly to a position where it does not inhibit work.
8. Disconnect harness clips, harness connectors, ground bol ts and blackets from steering member, and then
move the vehicle harness to the position without hindrance for work.
9. Remove mounting nuts, and then remove instrument stay (RH and LH).
10. Remove A/C unit assembly mounting bolts.
11. Remove mounting bolts, and then remove steering member from the vehicle.
12. Disconnect drain hose from A/C unit assembly, and then remove A/C unit assembly from the vehicle.
13. Remove mounting bolts, and then disconnect heater & cooling unit and blower unitassembly.
INSTALLATION
Note the following items, and install in the reverse order of removal.
CAUTION:
 Replace O-rings with new ones. Then apply compressor oil to them when installing.
 Check for leakages when recharging refrigerant. Refer to HA-18, "
Leak Test".
NOTE:
Refer to CO-9, "
Refilling" when filling radiator with engine coolant.
EVAPORATOR
EVAPORATOR : Removal and InstallationINFOID:0000000006276184
REMOVAL
1. Remove heater & cooling unit assembly. Refer to HA-41, "Exploded View".
2. Remove heater core. Refer to HA-44, "
HEATER CORE : Removal and Installation".
3. Remove mounting screws, and then remove evaporator pipe cover.
4. Remove air mix door motor (RH). Refer to HAC-153, "
AIR MIX DOOR MOTOR : Removal and Installa-
tion".
5. Remove mounting screws, and then remove A/C cover.
6. Remove foot duct LH. Refer to VTL-11, "
FLOOR DUCT 1 : Removal and Installation".
7. Remove mounting screws, and then remove A/C lower case.
8. Remove intake sensor. Refer to HAC-150, "
Removal and Installation".
9. Remove evaporator assembly from heater & cooling unit assembly.
10. Remove mounting bolts, and then remove evaporator from evaporator assembly.
CAUTION:
Cap or wrap the joint of the evaporator and evaporat or pipe assembly with suitable material such as
vinyl tape to avoid the entry of air.
Revision: 2010 May2011 QX56

REAR A/C UNITHA-49
< REMOVAL AND INSTALLATION >
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5. Pull out heater core (1) from rear A/C unit assembly.
INSTALLATION
Note the following item, and install in the reverse order of removal.
NOTE:
Refer to CO-9, "
Refilling" when filling radiator with engine coolant.
EXPANSION VALVE
EXPANSION VALVE : Removal and InstallationINFOID:0000000006276192
REMOVAL
1. Remove rear A/C unit assembly. Refer to HA-47, "REAR A/C UNIT ASSEMBLY : Removal and Installa-
tion".
2. Disassembly rear A/C unit assembly.
3. Remove mounting bolts, and then disconnect rear exp ansion valve assembly from rear evaporator pipe
assembly and rear cooler pipe assembly.
INSTALLATION
Note the following items, and install in the reverse order of removal.
CAUTION:
 Replace O-rings with new ones. Then apply compressor oil to them when installing.
 Check for leakages when recharging refrigerant. Refer to HA-18, "
Leak Test".
JMIIA0685ZZ
Revision: 2010 May2011 QX56

INT-10
< SYMPTOM DIAGNOSIS >
SQUEAK AND RATTLE TROUBLE DIAGNOSES
1. Trunk lid dumpers out of adjustment
2. Trunk lid striker out of adjustment
3. Trunk lid torsion bars knocking together
4. A loose license plate or bracket
Most of these incidents can be repaired by adjusting, securing, or insulating the item(s) or component(s) caus-
ing the noise.
SUNROOF/HEADLINING
Noises in the sunroof / headlining area can often be traced to one of the following items:
1. Sunroof lid, rail, linkage, or seals making a rattle or light knocking noise
2. Sunvisor shaft shaking in the holder
3. Front or rear windshield touching headlining and squeaking
Again, pressing on the components to stop the noise while duplicating the conditions can isolate most of these
incidents. Repairs usually consist of insulating with felt cloth tape.
SEATS
When isolating seat noise it is important to note t he position the seat is in and the load placed on the seat
when the noise occurs. These conditions should be duplic ated when verifying and isolating the cause of the
noise.
Causes of seat noise include:
1. Headrest rods and holder
2. A squeak between the seat pad cushion and frame
3. The rear seatback lock and bracket
These noises can be isolated by moving or pressing on the suspected components while duplicating the con-
ditions under which the noise occurs. Most of thes e incidents can be repaired by repositioning the component
or applying urethane tape to the contact area.
UNDERHOOD
Some interior noise may be caused by components under the hood or on the engine wall. The noise is then
transmitted into the passenger compartment.
Causes of transmitted underhood noise include:
1. Any component mounted to the engine wall
2. Components that pass through the engine wall
3. Engine wall mounts and connectors
4. Loose radiator mounting pins
5. Hood bumpers out of adjustment
6. Hood striker out of adjustment
These noises can be difficult to isolate since they cannot be reached from the interior of the vehicle. The best
method is to secure, move, or insulate one component at a time and test drive the vehicle. Also, engine RPM
or load can be changed to isolate the noise. Repairs can usually be made by moving, adjusting, securing, or
insulating the component causing the noise.
Revision: 2010 May2011 QX56