cooling INFINITI QX4 2005 Factory User Guide

ATC-22
LUBRICANT
Revision: October 20052005 QX56
LUBRICANTPFP:KLG00
Maintenance of Lubricant Quantity in CompressorEJS003X4
The lubricant in the compressor circulates through the system with the refrigerant. Add lubricant to compres-
sor when replacing any component or after a large refrigerant leakage has occurred. It is important to maintain
the specified amount.
If lubricant quantity is not maintained properly, the following malfunctions may result:

Lack of lubricant: May lead to a seized compressor

Excessive lubricant: Inadequate cooling (thermal exchange interference)
LUBRICANT
Name: NISSAN A/C System Lubricant Type S or equivalent
CHECKING AND ADJUSTING
CAUTION:
If excessive lubricant leakage is noted, do not perform the lubricant return operation.
Start the engine and set the following conditions:
Test Condition

Engine speed: Idling to 1,200 rpm

A/C switch: On

Blower speed: Max. position

Temp. control: Optional [Set so that intake air temperature is 25° to 30° C (77° to 86°F)]

Intake position: Recirculation ( )

Perform lubricant return operation for about ten minutes
Adjust the lubricant quantity according to the following table.
Lubricant Adjusting Procedure for Components Replacement Except Compressor
After replacing any of the following major components, add the correct amount of lubricant to the system.
Amount of lubricant to be added:

*1: If refrigerant leak is small, no addition of lubricant is needed.
Lubricant Adjustment Procedure for Compressor Replacement
1. Before connecting recovery/recycling equipment to vehicle, check recovery/recycling equipment gauges.
No refrigerant pressure should be displayed. If NG, recover refrigerant from equipment lines.
2. Connect recovery/recycling equipment to vehicle. Confirm refrigerant purity in supply tank using recovery/
recycling equipment and refrigerant identifier. If NG, refer to AT C - 5 , "
Contaminated Refrigerant" .
3. Confirm refrigerant purity in vehicle A/C system using recovery/recycling equipment and refrigerant identi-
fier. If NG, refer to AT C - 5 , "
Contaminated Refrigerant" .
4. Discharge refrigerant into the refrigerant recovery/recycling equipment. Measure lubricant discharged into
the recovery/recycling equipment.
5. Drain the lubricant from the “old” (removed) compressor into a graduated container and recover the
amount of lubricant drained.
6. Drain the lubricant from the “new” compressor into a separate, clean container.
7. Measure an amount of new lubricant installed equal to amount drained from “old” compressor. Add this
lubricant to “new” compressor through the suction port opening.
Part replacedLubricant to be added to system
Remarks
Amount of lubricant
m (US fl oz, Imp fl oz)
Front evaporator 75 (2.5, 2.6) —
Rear evaporator 75 (2.5, 2.6) —
Condenser 75 (2.5, 2.6) —
Liquid tank 5 (0.2, 0.2) Add if compressor is not replaced.
In case of refrigerant leak30 (1.0, 1.1) Large leak
— Small leak *1

ATC-38
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
How to Perform Trouble Diagnosis for Quick and Accurate RepairEJS003XF
WORK FLOW
SYMPTOM TABLE
*1AT C - 5 7 , "Operational Check (Front)"
or ATC-60, "
Operational Check
(Rear)" .
SHA9 00 E
Symptom Reference Page
A/C system does not come on. Go to Trouble Diagnosis Procedure for A/C System.AT C - 6 1
A/C system display is malfunctioning. Go to Navigation SystemAV- 6 1
A/C system cannot be controlled. Go to Self-diagnosis Function.AT C - 5 5
Air outlet does not change.
Go to Trouble Diagnosis Procedure for Mode Door Motor.AT C - 6 4
Mode door motor is malfunctioning.
Discharge air temperature does not change.
Go to Trouble Diagnosis Procedure for Air Mix Door Motor.AT C - 7 0
Air mix door motor is malfunctioning.
Intake door does not change.
Go to Trouble Diagnosis Procedure for Intake Door Motor.AT C - 8 3
Intake door motor is malfunctioning.
Defroster door motor is malfunctioning. Go to Trouble Diagnosis Procedure for Defroster Door Motor.AT C - 8 7
Front blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Front Blower Motor.AT C - 9 3
Rear blower motor operation is malfunction-
ing.Go to Trouble Diagnosis Procedure for Rear Blower Motor.AT C - 1 0 1
Rear discharge air temperature and/or air
outlet does not change.Go to Trouble Diagnosis Procedure for Rear Air Control circuit.AT C -11 2
Magnet clutch does not engage. Go to Trouble Diagnosis Procedure for Magnet Clutch.AT C -11 5
Insufficient cooling Go to Trouble Diagnosis Procedure for Insufficient Cooling.AT C - 1 2 1
Insufficient heating Go to Trouble Diagnosis Procedure for Insufficient Heating.AT C - 1 2 8
Noise Go to Trouble Diagnosis Procedure for Noise.AT C - 1 2 9
Self-diagnosis cannot be performed. Go to Trouble Diagnosis Procedure for Self-diagnosis.AT C - 1 3 2
Memory function does not operate. Go to Trouble Diagnosis Procedure for Memory Function.AT C - 1 3 3

ATC-58
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
CHECKING DISCHARGE AIR
1. Press MODE switch four times and the DEF switch.
2. Each position indicator should change shape (on display).
3. Confirm that discharge air comes out according to the air distri-
bution table. Refer to ATC-29, "
Discharge Air Flow" .
Mode door position is checked in the next step.
If NG, go to trouble diagnosis procedure for AT C - 6 4 , "
Mode Door
Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual
inspection) and intake door position is at fresh when the DEF or D/F
is selected.
CHECKING RECIRCULATION
1. Press recirculation ( ) switch one time. Recirculation indica-
tor should illuminate.
2. Press recirculation ( ) switch one more time. Recirculation
indicator should go off.
3. Listen for intake door position change (blower sound should
change slightly).
If NG, go to trouble diagnosis procedure for ATC-83, "
Intake Door
Motor Circuit" .
If OK, continue the check.
NOTE:
Confirm that the compressor clutch is engaged (sound or visual
inspection) and intake door position is at fresh when the DEF or D/F is selected.
CHECKING TEMPERATURE DECREASE
1. Rotate temperature control dial (driver side or passenger side)
counterclockwise until 16°C (60°F) is displayed.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to
trouble diagnosis procedure for ATC-121, "
Insufficient Cooling" . If
air mix door motor appears to be malfunctioning, go to ATC-72,
"DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR
(DRIVER)" or AT C - 7 6 , "DIAGNOSTIC PROCEDURE FOR AIR MIX
DOOR MOTOR (PASSENGER)" .
If OK, continue the check.
WJIA1045E
WJIA0528E
WJIA1046E
WJIA1047E

ATC-60
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
Operational Check (Rear)EJS003XM
The purpose of the operational check is to confirm that the system operates properly.
CHECKING BLOWER
1. Turn the rear blower control dial to switch position "1". Blower
should operate on low speed.
2. Turn the rear blower control dial counterclockwise to switch
position "2", "3", and "4" until all speeds are checked.
3. Leave blower on MAX speed.
If NG, go to trouble diagnosis procedure for ATC-101, "
Rear Blower
Motor Circuit" .
If OK, continue the check.
CHECKING TEMPERATURE DECREASE
1. Rotate temperature and mode dial fully counterclockwise.
2. Check for cold air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation if OK, go to
trouble diagnosis procedure for ATC-121, "
Insufficient Cooling" . If
air mix door motor appears to be malfunctioning, go to ATC-79,
"DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR
(REAR)" .
If OK, continue the check.
CHECKING TEMPERATURE INCREASE
1. Rotate temperature and mode dial clockwise.
2. Check for hot air at appropriate discharge air outlets.
If NG, listen for sound of air mix door motor operation. If OK, go to
trouble diagnosis procedure for ATC-128, "
Insufficient Heating" . If
air mix door motor appears to be malfunctioning, go to ATC-79,
"DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR
(REAR)" .
If OK, continue the check.Conditions : Engine running and at normal operating temperature
WJIA1350E
WJIA1069E
WJIA1070E

ATC-66
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
COMPONENT DESCRIPTION
Mode Door Motor
The mode door motor is attached to the heater & cooling unit. It
rotates so that air is discharged from the outlet as indicated by the
front air control. Motor rotation is conveyed to a link which activates
the mode door.
DIAGNOSTIC PROCEDURE FOR MODE DOOR MOTOR
1. CHECK FRONT AIR CONTROL FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Press the mode switch to the B/L ( ) mode.
3. Check voltage between front air control harness connector M49
terminal 5 and terminal 6 while pressing the mode switch to the
floor ( ) mode.
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
2. CHECK MODE DOOR MOTOR CIRCUITS FOR SHORT TO GROUND
1. Turn ignition switch OFF.
2. Disconnect the front air control harness connector.
3. Check continuity between front air control harness connector
M49 terminal 5, 6 and ground.
OK or NG
OK >> Replace front air control. Refer to ATC-147, "FRONT
AIR CONTROL" .
NG >> Repair or replace harness as necessary.
WJIA0587E
ConnectorTe r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
Front air control:
M496 5Press
mode
switchBattery
voltage
WJIA1727E
5 - Ground : Continuity should not exist.
6 - Ground : Continuity should not exist.
WJIA1734E

ATC-72
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
COMPONENT DESCRIPTION
Air Mix Door Motors
The driver and front passenger air mix door motors are attached to
the front heater & cooling unit. The rear air mix door motor is
attached to the rear heater & cooling unit. These motors rotate so
that the air mix door is opened or closed to a position set by the front
(or rear) air control. Motor rotation is then conveyed through a shaft
and the air mix door position is then fed back to the front air control
by the PBR built into the air mix door motors.
DIAGNOSTIC PROCEDURE FOR AIR MIX DOOR MOTOR (DRIVER)
1. CHECK FRONT AIR CONTROL FOR POWER AND GROUND
1. Turn ignition switch ON.
2. Rotate temperature control dial (driver) to 32°C (90°F).
3. Check voltage between front air control harness connector M49
terminal 3 and terminal 4 while rotating temperature control dial
(driver) to 16°C (60°F).
OK or NG
OK >> GO TO 3.
NG >> GO TO 2.
WJIA1876E
WJIA1877E
WJIA1245E
ConnectorTe r m i n a l s
Condition Voltage
(Approx.)
(+) (-)
Front air control:
M493 4Rotate temp
control dialBattery
voltage
WJIA1735E

ATC-88
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
SYSTEM DESCRIPTION
Component Parts
Defroster door control system components are:

Front air control

Defroster door motor

PBR (Built into defroster door motor)

In-vehicle sensor

Ambient sensor

Optical sensor

Intake sensor
System Operation
The front air control determines defroster door position based on the position of the defroster switch. When the
defroster switch is depressed, the defroster door motor rotates directing air to the defroster ducts. When any
mode other than defroster is selected, the defroster motor rotates in the opposite direction closing off air flow
to the defroster ducts.
In the AUTO mode, the front air control determines defroster door position based on the ambient temperature,
the intake air temperature and the in-vehicle temperature.
COMPONENT DESCRIPTION
Defroster door motor
The defroster door motor is attached to the front heater & cooling
unit. The front air control sends a voltage to rotate to the defroster
door directing the air flow either to the defroster ducts, or to the floor
ducts, depending on which way the voltage and ground are applied
to the motor leads. Motor rotation is conveyed to a lever which acti-
vates the defroster door.
WJIA1354E
WJIA0592E

TROUBLE DIAGNOSIS
ATC-95
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: October 20052005 QX56
Blower Speed Compensation - Sunload
When the in-vehicle temperature and the set temperature are very close, the blower will be operating at low
speed. The speed will vary depending on the sunload. During conditions of low or no sunload, the blower
operates at low speed. During high sunload conditions, the front air control causes the blower speed to
increase.
Blower Speed Control Specification
COMPONENT DESCRIPTION
Variable Blower Control
The variable blower control is located on the cooling unit. The vari-
able blower control receives a gate voltage from the front air control
to steplessly maintain the blower motor voltage in the 0 to 5 volt
range (approx.).
DIAGNOSTIC PROCEDURE FOR BLOWER MOTOR
SYMPTOM: Blower motor operation is malfunctioning under starting
blower speed control.
WJIA0441E
WJIA0559E
WJIA1358E

TROUBLE DIAGNOSIS
ATC-121
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: October 20052005 QX56
Insufficient CoolingEJS003XW
SYMPTOM: Insufficient cooling
INSPECTION FLOW
*1AT C - 5 7 , "Operational Check
(Front)"
*2AT C - 5 5 , "A/C System Self-diagno-
sis Function"
*3ATC-56, "SELF-DIAGNOSIS CODE
CHART"
*4EC-440, "SYSTEM DESCRIPTION"*5AT C - 5 , "Contaminated Refrigerant"*6ATC-122, "PERFORMANCE TEST
DIAGNOSES"
*7ATC-124, "Test Reading"*8EM-12, "Checking Drive Belts"*9ATC-133, "Water Valve Circuit"
WJIA1790E

TROUBLE DIAGNOSIS
ATC-125
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: October 20052005 QX56
TROUBLE DIAGNOSES FOR UNUSUAL PRESSURE
Whenever system′s high and/or low side pressure is unusual, diagnose using a manifold gauge. The marker
above the gauge scale in the following tables indicates the standard (usual) pressure range. Since the stan-
dard (usual) pressure, however, differs from vehicle to vehicle, refer to above table (Ambient air temperature-
to-operating pressure table).
Both High- and Low-pressure Sides are Too High
High-pressure Side is Too High and Low-pressure Side is Too Low
Gauge indication Refrigerant cycle Probable cause Corrective action
Both high- and low-pressure sides
are too high.Pressure is reduced soon
after water is splashed on
condenser.Excessive refrigerant charge
in refrigeration cycleReduce refrigerant until speci-
fied pressure is obtained.
Air suction by cooling fan is
insufficient.Insufficient condenser cooling
performance
↓
1. Condenser fins are clogged.
2. Improper fan rotation of
cooling fan

Clean condenser.

Check and repair cooling fan
if necessary.

Low-pressure pipe is not
cold.

When compressor is
stopped high-pressure
value quickly drops by
approximately 196 kPa (2
kg/cm
2 , 28 psi). It then
decreases gradually there-
after.Poor heat exchange in con-
denser
(After compressor operation
stops, high-pressure
decreases too slowly.)
↓
Air in refrigeration cycleEvacuate and recharge sys-
tem.
Engine tends to overheat.Engine cooling systems mal-
function.Check and repair engine cool-
ing system.

An area of the low-pres-
sure pipe is colder than
areas near the evaporator
outlet.

Plates are sometimes cov-
ered with frost.

Excessive liquid refrigerant
on low-pressure side

Excessive refrigerant dis-
charge flow

Expansion valve is open a
little compared with the
specification.
↓
Improper expansion valve
adjustmentReplace expansion valve.
AC359A
Gauge indication Refrigerant cycle Probable cause Corrective action
High-pressure side is too high and
low-pressure side is too low.
Upper side of condenser and
high-pressure side are hot,
however, liquid tank is not so
hot.High-pressure tube or parts
located between compressor
and condenser are clogged or
crushed.

Check and repair or replace
malfunctioning parts.

Check lubricant for contami-
nation.
AC360A