INFINITI QX56 2006 Factory Service Manual

ATC-180
REFRIGERANT LINES
Revision: November 20092006 QX56
CAUTION:

Replace the O-ring of the high-pressure pipe with a new one, then apply compressor oil to it when
installing it.

After charging refrigerant, check for leaks.
Removal and Installation for Low-pressure PipeEJS003YY
REMOVAL
1. Discharge the refrigerant. Refer to ATC-171, "HFC-134a (R-134a) Service Procedure" .
2. Remove the cowl top and the cowl top extension. Refer to EI-18, "
COWL TOP" .
3. Remove the low-pressure pipe. CAUTION:
Cap or wrap the joint of the pipes with suitable material such as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-173, "
Components" .
CAUTION:

Replace the O-ring of the high/low-pressure pipe with a new one, then apply compressor oil to it
when installing it.

After charging refrigerant, check for leaks.
Removal and Installation for Rear High- and Low-pressure A/C and Heater Core
Pipes
EJS005Y8
REMOVAL
1. Discharge the refrigerant. Refer to ATC-171, "HFC-134a (R-134a) Service Procedure" .
2. Drain the coolant from the engine cooling system. Refer to CO-10, "
Changing Engine Coolant" .
3. Disconnect the underfloor rear heater hoses (1 and 2) from the rear heater pipes underneath the vehicle.

⇐: Front
4. Remove the rear high- and low-pressure pipes bolt (A) to dis- connect the rear high- and low-pressure pipes from the under-
floor rear high- and low-pressure pipes underneath the vehicle.
CAUTION:
Cap or wrap the joint of the pipes with suitable material
such as vinyl tape to avoid the entry of air.
5. Remove the rear high- and low-pressure pipes nuts (B) under- neath the vehicle.
NOTE:
The remaining steps are performed inside the rear luggage area of the vehicle.
6. Remove the luggage side finisher lower RH. Refer to EI-40, "
LUGGAGE FLOOR TRIM" .
7. Disconnect the rear heater core hoses (1 and 2) from the rear heater core (3).

⇐: Front
WJIA2310E
WJIA2311E

REFRIGERANT LINESATC-181
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
8. Remove the rear high- and low-pressure pipes bracket bolt (A)
to release the bracket.

Rear blower motor (1)

⇐: Front
9. Remove the rear high- and low-pressure pipes bolt (A) to dis- connect the rear high- and low-pressure pipes from the rear
expansion valve (1).

⇐: Front
CAUTION:
Cap or wrap the joint of the pipes with suitable material
such as vinyl tape to avoid the entry of air.
10. Disconnect the following electrical connectors:

Rear air mix door motor (1)

Rear blower motor resistor (2)

Rear blower motor (3)

⇐ : Front
11. Disconnect the ducts from the rear heater and cooling unit assembly. Refer to ATC-166, "
Components" .
12. Remove the rear heater and cooling unit assembly. CAUTION:
Cap or wrap the joint of the pipes with suitable material such as vinyl tape to avoid the entry of air.
13. Remove the rear high- and low-pressure A/C pipes.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-173, "
Components" .
CAUTION:

Replace the O-ring of the high/low-pressure pipe with a new one, then apply compressor oil to it
when installing it.

After charging refrigerant, check for leaks.
Removal and Installation for Underfloor Rear High- and Low-pressure A/C and
Heater Core Pipes
EJS005Y9
REMOVAL
1. Drain the coolant from the engine cooling system. Refer to CO-10, "Changing Engine Coolant" .
2. Disconnect the battery negative terminal.
3. Disconnect the generator harness.
4. Discharge the refrigerant. Refer to ATC-171, "
HFC-134a (R-134a) Service Procedure" .
WJIA2312E
WJIA2313E
WJIA2314E

ATC-182
REFRIGERANT LINES
Revision: November 20092006 QX56
5. Remove the front and rear bumper fascia. Refer to EI-13, "FRONT BUMPER" (front), EI-15, "REAR
BUMPER" (rear).
6. Reposition the front fender protector out of the way. Refer to EI-23, "
FENDER PROTECTOR" .
7. Disconnect the chassis harness connector.
8. Remove the spare wheel and tire.
9. Remove the tailpipe and tailpipe hanger bracket. Refer to EX-3, "
Removal and Installation" .
10. Remove the seatbelt latch anchor. Refer to RSU-26, "
Components" .
11. Remove the front floor heat shield.
12. Disconnect each end of the underfloor rear high- and low-pressure A/C and heater core pipes. Refer to ATC-173, "
Components" .
CAUTION:
Cap or wrap the joint of the pipes with suitable material such as vinyl tape to avoid the entry of air.
13. Set two suitable jacks at the RH body mount points to support the vehicle body when it is separated from the RH side of the frame.
14. Remove the RH body mount bolts. Refer to BL-159, "
Body Mounting" .
15. Use the vehicle hoist to lower the RH side of the frame from the RH side of the body [approximately 305 mm (12 in)] until there is sufficient clearance to remove the underfloor rear high- and low-pressure A/C
and heater core pipes from between the body and the frame.
16. Remove the underfloor rear high- and low-pressure A/C and heater core pipes from the back of the vehi- cle.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-173, "
Components" .
CAUTION:

Replace the O-ring of the high/low-pressure pipe with a new one, then apply compressor oil to it
when installing it.

After charging refrigerant, check for leaks.
Removal and Installation for Refrigerant Pressure SensorEJS003YZ
REMOVAL
1. Discharge the refrigerant. Refer to ATC-171, "HFC-134a (R-134a) Service Procedure" .
2. Disconnect the refrigerant pressure sensor electrical connector and remove the refrigerant pressure sensor from the condenser.
CAUTION:
Be careful not to damage the condenser fins.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-173, "
Components" .
CAUTION:

Be careful not to damage the condenser fins.

Replace the O-ring of the refrigerant pressure sensor with a new one, then apply compressor oil to
it when installing it.

After charging refrigerant, check for leaks.
Removal and Installation for CondenserEJS003Z0
REMOVAL
1. Discharge the refrigerant. Refer to ATC-171, "HFC-134a (R-134a) Service Procedure" .
LJIA0145E

REFRIGERANT LINESATC-183
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
2. Remove the radiator. Refer to CO-14, "RADIATOR" .
CAUTION:
Be careful not to damage the core surface of the condenser and the radiator.
3. Disconnect the high-pressure flexible hose and the high-pressure pipe from the condenser. CAUTION:
Cap or wrap the joint of the pipe with suitable material such as vinyl tape to avoid the entry of air.
4. Disconnect the refrigerant pressure sensor connector.

Remove the refrigerant pressure sensor from the condenser
as necessary.
5. Lift the condenser out of the mounting grommets to remove the condenser.
INSTALLATION
Installation is in the reverse order of removal.
Refer to ATC-173, "
Components" .
CAUTION:

Replace the O-rings of the high-pressure pipe, refrigerant pressure sensor, and high-pressure
flexible hose with new ones, then apply compressor oil to them when installing them.

After charging refrigerant, check for leaks.

Replace the grommets as necessary.
LJIA0145E

ATC-184
REFRIGERANT LINES
Revision: November 20092006 QX56
Removal and Installation for Front EvaporatorEJS003Z1
Front Heater and Cooling Unit Assembly
REMOVAL
1. Remove the front heater core. Refer to ATC-157, "FRONT HEATER CORE" .
LJIA0138E
1. Heater core cover2. Heater core pipe bracket 3. Heater core
4. Upper bracket 5. Upper heater and cooling unit case 6. A/C evaporator
7. Lower heater and cooling unit case 8. Blower motor 9. Variable blower control

REFRIGERANT LINESATC-185
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
2. Remove the defroster mode door arm.
3. Separate the heater core and cooling unit case.
4. Remove the evaporator.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
Replace the O-rings on the low-pressure flexible hose and the high-pressure pipe with new ones.
Apply compressor oil to the O-rings when installing them.
Removal and Installation for Rear EvaporatorEJS003Z2
Rear Heater and Cooling Unit Assembly
LJIA0135E
1. Front cover2. Evaporator and heater core case 3. Evaporator
4. Side cover 5. Heater core6. Rear blower motor
7. Blower motor case 8. Rear blower motor resistor

ATC-186
REFRIGERANT LINES
Revision: November 20092006 QX56
REMOVAL
1. Remove the rear heater and cooling unit assembly from the vehicle. Refer to ATC-155, "REAR HEATER
AND COOLING UNIT ASSEMBLY" .
2. Remove the rear blower motor.
3. Remove the rear blower speed resistor.
4. Remove the rear air mix door motor.
5. Remove the rear duct and blend door assembly. Refer to AT C -
170, "REAR OVERHEAD DUCTS" .
6. Disassemble the rear heater and cooling unit assembly to remove the evaporator.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:

Replace the O-rings on the rear A/C pipes with new ones. Apply compressor oil to the O-rings
when installing them.

After charging refrigerant, check for leaks.
Removal and Installation for Front Expansion ValveEJS003Z3
REMOVAL
1. Discharge the refrigerant. Refer to ATC-171, "HFC-134a (R-134a) Service Procedure" .
2. Remove the front evaporator. Refer to ATC-184, "
Removal and Installation for Front Evaporator" .
3. Remove the cooler grommet.
4. Remove the expansion valve.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:

Replace the O-rings on the A/C refrigerant pipes with new ones, then apply compressor oil to them
when installing them.

After charging refrigerant, check for leaks.
Removal and Installation for Rear Expansion ValveEJS003Z4
REMOVAL
1. Discharge the refrigerant. Refer to ATC-171, "HFC-134a (R-134a) Service Procedure" .
2. Remove the luggage side lower finisher RH. Refer to EI-40, "
LUGGAGE FLOOR TRIM" .
3. Disconnect the A/C refrigerant pipes from the expansion valve.
LJIA0021E
WJIA0582E
Expansion valve bolts : 4 N·m (0.41 kg-m, 35 in-lb)
A/C refrigerant pipe to expansion valve bolt : Refer to ATC-173, "
Components"
.

REFRIGERANT LINESATC-187
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
CAUTION:
Cap or wrap the A/C refrigerant pipe ends with a suitable material such as vinyl tape to avoid the
entry of air and contaminants.
4. Remove the expansion valve.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:

Replace the O-rings on the A/C refrigerant pipes with new ones, then apply compressor oil to them
when installing them.

After charging refrigerant, check for leaks.
Checking for Refrigerant LeaksEJS003Z5
PRELIMINARY CHECK
Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C oil leak-
age, damage, and corrosion. Any A/C oil leakage may indicate an area of refrigerant leakage. Allow extra
inspection time in these areas when using either an electronic refrigerant leak detector (J-41995) or fluores-
cent dye leak detector (J-42220).
If any dye is observed using a fluorescent dye leak detector (J-42220), confirm the leak using a electronic
refrigerant leak detector (J-41995). It is possible that the dye is from a prior leak that was repaired and not
properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electronic refrigerant leak detector (J-41995), move the probe
along the suspected leak area at 25 - 50 mm (1 - 2 in) per second and no further than 6 mm (1/4 in) from the
component.
CAUTION:
Moving the electronic refrigerant leak detector probe slower and closer to the suspected leak area will
improve the chances of finding a leak.
Checking System for Leaks Using the Fluorescent Dye Leak DetectorEJS003Z6
1. Check the A/C system for leaks using the fluorescent dye leak detector and safety goggles (J-42220) in a low sunlight area (area without windows preferable). Illuminate all components, fittings and lines. The dye
will appear as a bright green/yellow area at the point of leakage. Fluorescent dye observed at the evapo-
rator drain opening indicates an evaporator core assembly leak (tubes, core or expansion valve).
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or cloth, then inspect the shop rag or cloth with the fluorescent dye leak detector (J-42220) for dye residue.
3. After the leak is repaired, remove any residual dye using refrigerant dye cleaner (J-43872) to prevent future misdiagnosis.
4. Perform a system performance check and then verify the leak repair using a electronic refrigerant leak detector (J-41995).
NOTE:

Other gases in the work area or substances on the A/C components, for example, anti-freeze, wind-
shield washer fluid, solvents and oils, may falsely trigger the leak detector. Make sure the surfaces to
be checked are clean.

Clean with a dry cloth or blow off with shop air.

Do not allow the sensor tip of the electronic refrigerant leak detector (J-41995) to contact with any sub-
stance. This can also cause false readings and may damage the detector.
Dye InjectionEJS003Z7
NOTE:
This procedure is only necessary when recharging the system or when the compressor has seized and must
be replaced.
1. Check the A/C system static (at rest) pressure. Pressure must be at least 345 kPa (3.52 kg/cm
2 , 50 psi).
Expansion valve bolts : 4 N·m (0.41 kg-m, 35 in-lb)
A/C refrigerant pipe to expansion valve bolt : Refer to
ATC-173, "
Components"
.

ATC-188
REFRIGERANT LINES
Revision: November 20092006 QX56
2. Pour one bottle 7.4 cc (1/4 ounce) of the HFC-134a (R-134a) fluorescent leak detection dye (J-41447) into
the HFC-134a (R-134a) dye injector (J-41459).
CAUTION:
If repairing the A/C system or replacing a component, pour the HFC-134a (R-134a) fluorescent leak
detection dye (J-41447) directly into the open system connection and proceed with the service
procedures.
3. Connect the refrigerant dye injector (J-41459) to the low-pressure service valve.
4. Start the engine and switch the A/C system ON.
5. When the A/C system is operating (compressor running), inject one bottle 7.4 cc (1/4 ounce) of HFC-134a (R-134a) fluorescent leak detection dye (J-41447) through the low-pressure service valve using HFC-
134a (R-134a) dye injector (J-41459). Refer to the manufacturer's operating instructions.
6. With the engine still running, disconnect the HFC-134a (R-134a) dye injector (J-41459) from the low-pres- sure service valve.
7. Operate the A/C system for a minimum of 20 minutes to mix the HFC-134a (R-134a) fluorescent leak detection dye (J-41447) with the A/C system oil. Depending on the leak size, operating conditions and
location of the leak, it may take from minutes to days for the HFC-134a (R-134a) fluorescent leak detec-
tion dye to penetrate an A/C system leak and become visible.
Electronic Refrigerant Leak DetectorEJS003Z8
PRECAUTIONS FOR HANDLING LEAK DETECTOR
NOTE:
When performing a refrigerant leak check, use a electronic refrigerant leak detector (J-41995) or equivalent.
Ensure that the electronic refrigerant leak detector (J-41995) is calibrated and set properly according to the
manufacturer's operating instructions.
The electronic refrigerant leak detector (J-41995) is a delicate
device. To use the electronic refrigerant leak detector (J-41995)
properly, read the manufacturer's operating instructions and perform
any specified maintenance.
1. Position the probe approximately 5 mm (3/16 in) away from thepoint to be checked as shown.
AHA281A
SHA707EA

REFRIGERANT LINESATC-189
C
DE
F
G H
I
K L
M A
B
AT C
Revision: November 2009 2006 QX56
2. When checking for leaks, circle each fitting completely with the
probe as shown.
3. Move the probe along each component at a speed of approxi- mately 25 - 50 mm (1 - 2 in)/second as shown.
CHECKING PROCEDURE
NOTE:
To prevent inaccurate or false readings, make sure there is no refrigerant vapor, shop chemicals, or cigarette
smoke in the vicinity of the vehicle. Perform the leak test in a calm area (low air/wind movement) so that the
leaking refrigerant is not dispersed.
1. Turn the engine OFF.
2. Connect the manifold gauge set (J-39183-C) to the A/C service ports. Refer to ATC-171, "
SETTING OF
SERVICE TOOLS AND EQUIPMENT" .
3. Check if the A/C refrigerant pressure is at least 345 kPa (3.52 kg/cm
2 , 50 psi) above a temperature of
16 °C (61 °F). If less than specification, recover/evacuate and recharge the system with the specified
amount of refrigerant. Refer to ATC-171, "
HFC-134a (R-134a) Service Procedure" .
NOTE:
At temperatures below 16 °C (61 °F), leaks may not be detected since the system may not reach 345 kPa
(3.52 kg/cm
2 , 50 psi) pressure.
4. Perform the leak test from the high-pressure side (front A/C compressor discharge “a” to evaporator inlet
“f ” or rear piping connection “l”) to the low-pressure side (front A/C evaporator drain hose “g” to shaft seal
“k ” and rear A/C evaporator drain hose “o ” to piping connection “r”). Refer to ATC-173, "
Components" .
Clean the component to be checked and carefully move the electronic refrigerant leak detector probe
completely around the following connections and components.

Check the compressor shaft seal

Check the high and low-pressure pipe and hose fittings, relief valve, and compressor shaft seal

Check the liquid tank

Check the refrigerant pressure sensor

Check all around the service valves. Check that the service valve caps are screwed tightly on the ser-
vice valves (to prevent leaks).
NOTE:
After removing manifold gauge set (J-39183-C) from the service valves, wipe any residue from the ser-
vice valves to prevent any false readings by the electronic refrigerant leak detector (J-41995).

Evaporator
With engine OFF, turn blower fan on “High” for at least 15 seconds to dissipate any refrigerant trace in
the heater and cooling unit assembly. Wait a minimum of 10 minutes accumulation time (refer to the
manufacturer's recommended procedure for actual wait time) before inserting the electronic refrigerant
leak detector probe into the heater and cooling unit assembly drain hose.
SHA706E
SHA708EA