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HIGH-PRESSURE PIPEHA-41
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HIGH-PRESSURE PIPE
Removal and Installation for High-Pressure PipeINFOID:0000000003775316
REMOVAL
1. Remove the cowl top extension. Refer to EXT-18, "Removal and Installation".
2. Disconnect the battery negative termi nal and positive battery terminal.
3. Reposition the IPDM E/R aside.
4. Remove the front left wheel and tire assembly. Refer to MA-29, "Rotation"
.
5. Position aside the front floor insulator.
6. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure"
.
7. Remove the low pressure pipe. Refer to HA-37, "Removal and Installation for Low-Pressure Pipe"
.
8. 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:0000000003775317
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-pressu re 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).
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-42
< ON-VEHICLE REPAIR >
HIGH-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 Installation for Underfloor Rear High- and Lo w-Pressure A/C and Heater
Core Pipes
INFOID:0000000003775318
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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HIGH-PRESSURE PIPEHA-43
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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 protec tor 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-6, "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 suffici ent 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.
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HA-44
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CONDENSER
CONDENSER
Removal and Installation for CondenserINFOID:0000000003775319
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Remove the radiator. Refer to CO-15, "Removal and Installation"
.
CAUTION:
Be careful not to damage the core su rface 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 ma terial such as vinyl tape to avoid the entry of air.
4. Disconnect the refrigerant pressure sensor connector. Remove the refrigerant pressure sensor from the condenseras 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 HA-29, "Component"
.
CAUTION:
Replace the O-rings of the high-p ressure pipe, refrigerant pressure sensor, and high-pressure flexi-
ble hose with new ones, then apply compr essor oil to them when installing them.
After charging refrigerant, check for leaks.
Replace the grommets as necessary.
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HA-46
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REFRIGERANT PRESSURE SENSOR
REFRIGERANT PRESSURE SENSOR
Removal and Installation for Refrigerant Pressure SensorINFOID:0000000003775321
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Disconnect the refrigerant pressu re 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 HA-29, "Component"
.
CAUTION:
Be careful not to damage the condenser fins.
Replace the O-ring of the refriger ant pressure sensor with a new one, then apply compressor oil to it
when installing it.
After charging refrigerant, check for leaks.
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EXPANSION VALVEHA-47
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EXPANSION VALVE
Removal and Installation for Front Expansion ValveINFOID:0000000003775322
REMOVAL
1. Discharge the refrigerant. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Remove the front evaporator. Refer to VTL-35, "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 re frigerant pipes with new ones, then apply compressor oil to them
when installing them.
After charging refrigerant, check for leaks.
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Expansion valve bolts : 4 N·m (0.41 kg-m, 35 in-lb)
A/C refrigerant pipe to expansion valve bolt : Refer to HA-29, "Component"
.
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HA-48
< ON-VEHICLE REPAIR >
LIQUID TANK
LIQUID TANK
Removal and Installation of Liquid TankINFOID:0000000005873219
REMOVAL
1. Remove the condenser. Refer to HA-44, "Removal and Installation for Condenser" .
2. Clean liquid tank and its surrounding area, and remove dirt and rust from liquid tank. CAUTION:
Be sure to clean carefully.
3. Remove bracket bolt (A) and liquid tank attachment bolt (B) from liquid tank (1).
4. Remove liquid tank bracket (1) from protruding part of con- denser (2).
5. Slide liquid tank (3) upward away from condenser mounting block, and remove liquid tank (3).
INSTALLATION
Installation is in the reverse order of removal.
NOTE:
Be careful to align the threaded liquid tank attachment bolt hole (A)
with condenser mounting block (B).
CAUTION:
Make sure liquid tank attachment bolt is securely installed atcondenser mounti ng block (B).
Always replace O-rings for A/C piping with new ones, and
apply compressor oil when installing.
When recharging refrigeran t, check for leaks. Refer to HA-24,
"Checking of Refrigerant Leaks" .
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![INFINITI QX56 2009 Factory Service Manual BLOWER MOTOR CONTROL SYSTEMHAC-53
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Check 20A fuses [No. 24 and 27 (Located in the fuse and fusible link box)]. For INFINITI QX56 2009 Factory Service Manual BLOWER MOTOR CONTROL SYSTEMHAC-53
< COMPONENT DIAGNOSIS > [AUTOMATIC AIR CONDITIONER]
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Check 20A fuses [No. 24 and 27 (Located in the fuse and fusible link box)]. For](/manual-img/42/57031/w960_57031-2365.png)
BLOWER MOTOR CONTROL SYSTEMHAC-53
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Check 20A fuses [No. 24 and 27 (Located in the fuse and fusible link box)]. For fuse layout. Refer to PG-72,
"Terminal Arrangement".
Is the inspection result normal?
YES >> GO TO 2.
NO >> GO TO 7.
2.CHECK FRONT BLOWER MOTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect front blower motor connector.
3. Turn ignition switch ON.
4. Press the A/C switch.
5. Press the front blower contro l "+" switch to maximum speed.
6. Check voltage between front blower motor harness connector
M62 terminal 2 and ground.
Is the inspection result normal?
YES >> GO TO 10.
NO >> GO TO 3.
3.CHECK FRONT BLOWER MOTOR RELAY (S WITCH SIDE) POWER SUPPLY CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect front blower motor relay.
3. Check voltage between front blower motor relay harness con- nector M107 terminal 5 and ground.
Is the inspection result normal?
YES >> GO TO 4.
NO >> Repair harness or connector.
4.CHECK FRONT BLOWER MOTOR RELAY
Turn ignition switch OFF.
Check front blower motor relay. Refer to HAC-55, "
Front Blower Motor Component Inspection".
Is the inspection result normal?
YES >> GO TO 5.
NO >> Replace front blower motor relay.
5.CHECK FRONT BLOWER MOTOR RELA Y (SWITCH SIDE) CIRCUIT FOR OPEN
Check continuity between front bl ower motor relay harness connec-
tor M107 terminal 3 and front blower motor harness connector M62
terminal 2.
Is the inspection result normal?
YES >> GO TO 6.
NO >> Repair harness or connector.
6.CHECK FRONT BLOWER MOTOR RELAY (COIL SIDE) POWER SUPPLY Fuses are good.
2 - Ground
: Battery voltage
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5 - Ground: Battery voltage
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3 - 2 : Continuity should exist.
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