2008 INFINITI QX56 heater

ELECTRICAL LEAK DETECTORHA-27
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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 t here 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 HA-20, "
HFC-134a (R-
134a) Service Procedure".
3. Check if the A/C refrigerant pressu re 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/ev acuate and recharge the system with the specified
amount of refrigerant. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
NOTE:
At temperatures below 16 °C (61° F), leaks may not be detected sinc e 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 HA-29, "
Component". 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 fitt ings, 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.
NOTE:
SHA706E
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HA-28
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ELECTRICAL LEAK DETECTOR
Keep the probe inserted for at least 10 seconds. Use caution not to contaminate the probe tip with water
or dirt that may be in the drain hose.
5. If a leak is detected, verify at least once by blowing compressed air into the area of the suspected leak, then repeat the leak check.
6. Do not stop when one leak is found. Continue to check for additional leaks at all system components and connections.
7. If no leaks are found, perform steps 8 - 11.
8. Start the engine.
9. Set the heater A/C controls as follows: NOTE:
For the automatic system, turn OF F the automatic controls and set the heater A/C controls manually.
a. A/C switch to ON
b. Air flow to VENT mode
c. Intake position to RECIRCULATION mode
d. Temperature to MAX cold
e. Blower fan speed to HIGH
10. Run the engine at 1,500 rpm for at least 2 minutes.
11. Turn the engine OFF and perform the leak check again following steps 4 through 6 above.
Refrigerant leaks should be checked immediately after turning
the engine OFF. Begin with the leak detector at the compressor.
The pressure on the high pressure side will gradually drop after
the refrigerant circulation stops and pressure on the low pres-
sure side will gradually rise, as shown in the graph. Some leaks
are more easily detected when the pressure is high.
12. Before connecting the recovery/recycling equipment to the vehicle, check the recovery/recycling equip-
ment gauges. No refrigerant pressure should be displayed. If pressure is displayed, recover the refriger-
ant from the equipment lines and t hen check the refrigerant purity.
13. Confirm refrigerant purity in supply tank using recovery/recycling equipment and refrigerant identifier
equipment (J-41810-NI).
14. Confirm the refrigerant purity in the vehicle's A/C system using recovery/recycling equipment and refriger-
ant identifier equipment (J-41810-NI).
15. Discharge the A/C system using recovery/recycling equipment. Repair the leaking fitting or component as
necessary.
16. Evacuate and recharge the A/C system and perform the leak test to confirm th\
at there are no refrigerant leaks.
17. Conduct the Operational Check to ensure system works properly. Refer to HAC-108,
"SymptomMatrixChart" and HAC-110, "Diagnostic Work Flow".
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HA-30
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REFRIGERATION SYSTEM
Rear A/C System
NOTE:
Refer to HA-5, "
Precaution for Refrigerant Connection".
1. High-pressure service valve 2. Grommet 3. High-pressure pipe
4. Refrigerant pressure sensor 5. Condenser 6. Compressor shaft seal
7. High-pressure flexible hose 8. Low-pressure flexible hose 9. Low-pressure service valve
10. Low-pressure pipe 11. Expansion valve (front)12. Drain hose
AWIIA0134GB
1. Rear heater and cooling unit assembly 2. Rear A/C pipes 3. Rear A/C heater core pipes
4. Rear heater core hose 5. Rear blower motor6. Underfloor rear A/C pipes
7. Underfloor rear heater core pipes A. Bolt torque specification B. Leak checking order (l - r)
C. Tightening torque D. Wrench sizeE. O-ring size
⇐ Front
NOTE: The O-ring size 8 is the high-side and the O-ring size 16 is the low-side.
Revision: March 2010 2008 QX56

LOW-PRESSURE PIPEHA-37
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LOW-PRESSURE PIPE
Removal and Installation for Low-Pressure PipeINFOID:0000000001516655
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Remove the cowl top and the cowl top extension. Refer to EXT-18, "
Removal and Installation".
3. Remove the low-pressure pipe. CAUTION:
Cap or wrap the joint of the pipes with suitable material such as viny l tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
Refer to HA-29, "
Component".
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
INFOID:0000000002975446
REMOVAL
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
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 avo id the entry of air.
5. Remove the rear high- and low-pressure pipes nuts (B).
NOTE:
The remaining steps are performed inside the rear luggage area of the vehicle.
6. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
7. Disconnect the rear heater core hoses (1 and 2) from the rear heater core (3).
• : Front
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HA-38
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LOW-PRESSURE PIPE
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 variable blower control (2)
• Rear blower motor (3)
• : Front
11. Disconnect the ducts from the rear heater and cooling unit assembly. Refer to HA-29, "
Component".
12. Remove the rear heater and cooling unit assembly. CAUTION:
Cap or wrap the joint of the pipes with suitable material such as viny l 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 HA-29, "
Component".
CAUTION:
• Replace the O-rings on the rear high- and low-pr essure A/C pipes with a new ones, then apply com-
pressor oil to them for installation.
• After charging the refrigerant, check for leaks.
Removal and Installati on for Underfloor Rear High- and Low-Pressure A/C and Heater
Core Pipes
INFOID:0000000002975447
REMOVAL
1. Drain the engine coolant. Refer to CO-11, "Changing Engine Coolant".
2. Disconnect the battery negative terminal.
3. Disconnect the generator harness.
4. Discharge the refrigerant. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
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LOW-PRESSURE PIPEHA-39
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5. Remove the front and rear bumper fascia. Refer to EXT-13, "Removal and Installation" (front), EXT-15,
"Removal and Installation" (rear).
6. Reposition the front fender protector out of the way. Refer to EXT-23, "
Removal and Installation".
7. Disconnect the chassis harness connector.
8. Remove the spare wheel and tire.
9. Remove the tailpipe and tailpipe hanger bracket. Refer to EX-6, "
Removal and Installation".
10. Remove the seatbelt latch anchor. Refer to EX-6, "
Removal and Installation".
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 HA-29, "
Component".
CAUTION:
Cap or wrap the joint of the pipes with suitable material such as viny l 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 BRM-2, "
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.
CAUTION:
• Replace the O-rings of the underfloor rear high - and low-pressure A/C and heater core pipes with
new ones, then apply compressor oil to them for installation.
• After charging refrigerant, check for leaks.
Revision: March 2010 2008 QX56

HIGH-PRESSURE PIPEHA-41
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HIGH-PRESSURE PIPE
Removal and Installation for High-Pressure PipeINFOID:0000000001516657
REMOVAL
1. Remove the cowl top extension. Refer to EXT-18, "Removal and Installation".
2. Disconnect the battery negative terminal and positive battery terminal.
3. Reposition the IPDM E/R aside.
4. Remove the front right wheel and tire assembly. Refer to WT-48, "
Rotation".
5. Remove front right fender protector. Refer to EXT-23, "
Removal and Installation"
6. Position aside the front floor insulator.
7. Discharge the refrigerant. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
8. Remove the low pressure pipe. Refer to HA-37, "
Removal and Installation for Low-Pressure Pipe".
9. Remove the high-pressure pipe. CAUTION:
Cap or wrap the joint of the pipe with suitable mate rial such as vinyl tape to avoid the entry of air.
INSTALLATION
Installation is in the reverse order of removal.
Refer to HA-29, "
Component".
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 Rear High- and Low-Pressure A/C and Heater Core Pipes
INFOID:0000000002975448
REMOVAL
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
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 avo id the entry of air.
5. Remove the rear high- and low-pressure pipes nuts (B).
NOTE:
The remaining steps are performed inside the rear luggage area of the vehicle.
6. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
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HA-42
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HIGH-PRESSURE PIPE
7. Disconnect the rear heater core hoses (1 and 2) from the rearheater core (3).
• : Front
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 variable blower control (2)
• Rear blower motor (3)
• : Front
11. Disconnect the ducts from the rear heater and cooling unit assembly. Refer to HA-29, "
Component".
12. Remove the rear heater and cooling unit assembly. CAUTION:
Cap or wrap the joint of the pipes with suitable material such as viny l 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 HA-29, "
Component".
CAUTION:
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