air conditioning INFINITI QX4 2001 Factory User Guide
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PERFORMANCE CHARTNBHA0031Test ConditionNBHA0031S01Testing must be performed as follows:
Vehicle location Indoors or in the shade (in a well-ventilated place)
Doors Closed
Door window Open
Hood Open
TEMP. Max. COLD
Mode switch
(Ventilation) set
REC switch
(Recirculation) set
(blower) speed Max. speed set
Engine speed Idle speed
Operate the air conditioning system for 10 minutes before taking measurements.
Test ReadingNBHA0031S02Recirculating-to-discharge Air Temperature TableNBHA0031S0201
Inside air (Recirculating air) at blower assembly inlet
Discharge air temperature at center ventilator
ÉC (ÉF) Relative humidity
%Air temperature
ÉC (ÉF)
50-6025 (77) 6.0 - 9.0 (43 - 48)
30 (86) 10.0 - 13.6 (50 - 56)
35 (95) 15.2 - 19.5 (59 - 67)
40 (104) 22.5 - 27.1 (73 - 81)
60-7025 (77) 9.0 - 12.2 (48 - 54)
30 (86) 13.6 - 17.2 (56 - 63)
35 (95) 19.5 - 23.7 (67 - 75)
40 (104) 27.1 - 32.3 (81 - 90)
Ambient Air Temperature-to-operating Pressure TableNBHA0031S0202
Ambient air
High-pressure (Discharge side)
kPa (kg/cm
2, psi)Low-pressure (Suction side)
kPa (kg/cm2, psi) Relative humidity
%Air temperature
ÉC (ÉF)
50-7025 (77)1,226 - 1,638
(12.5 - 16.7, 178 - 237)172 - 250 (1.75 - 2.55, 25 - 36)
30 (86)1,422 - 1,883
(14.5 - 19.2, 206 - 273)196 - 275 (2.0 - 2.8, 28 - 40)
35 (95)1,657 - 2,187
(16.9 - 22.3, 240 - 317)231 - 309 (2.35 - 3.15, 33 - 45)
40 (104)1,922 - 2,501
(19.6 - 25.5, 279 - 363)280 - 373 (2.85 - 3.8, 41 - 54)
TROUBLE DIAGNOSES FOR ABNORMAL PRESSURENBHA0032Whenever system's high and/or low side pressure is abnormal, diagnose using a manifold gauge. The marker
above the gauge scale in the following tables indicates the standard (normal) pressure range. Since the stan-
dard (normal) pressure, however, differs from vehicle to vehicle, refer to HA-116 (ªAmbient air temperature-
to-operating pressure tableº).
TROUBLE DIAGNOSES
Insufficient Cooling (Cont'd)
HA-116
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Low-pressure Side Sometimes Becomes Negative.NBHA0032S05
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side sometimes
becomes negative.
AC354A
IAir conditioning system
does not function and
does not cyclically cool the
compartment air.
IThe system constantly
functions for a certain
period of time after com-
pressor is stopped and
restarted.Refrigerant does not dis-
charge cyclically.
"
Moisture is frozen at expan-
sion valve outlet and inlet.
"
Water is mixed with refriger-
ant.IDrain water from refriger-
ant or replace refrigerant.
IReplace liquid tank.
Low-pressure Side Becomes Negative.NBHA0032S06
Gauge indication Refrigerant cycle Probable cause Corrective action
Low-pressure side becomes nega-
tive.
AC362A
Liquid tank or front/rear side
of expansion valve's pipe is
frosted or dewed.High-pressure side is closed
and refrigerant does not flow.
"
Expansion valve or liquid
tank is frosted.Leave the system at rest
until no frost is present. Start
it again to check whether or
not the problem is caused by
water or foreign particles.
IIf water is the cause, ini-
tially cooling is okay. Then
the water freezes causing
a blockage. Drain water
from refrigerant or replace
refrigerant.
IIf due to foreign particles,
remove expansion valve
and remove the particles
with dry and compressed
air (not shop air).
IIf either of the above
methods cannot correct
the problem, replace
expansion valve.
IReplace liquid tank.
ICheck lubricant for con-
tamination.
TROUBLE DIAGNOSES
Insufficient Cooling (Cont'd)
HA-120
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NBMA0003
General maintenance includes those items which should be checked during the normal day-to-day operation
of the vehicle. They are essential if the vehicle is to continue operating properly. The owners can perform
checks and inspections themselves or they can have their INFINITI dealers do them.
OUTSIDE THE VEHICLE
The maintenance items listed here should be performed from time to time, unless otherwise specified.
ItemReference page
TiresCheck the pressure with a gauge periodically when at a service station,
including the spare, and adjust to the specified pressure if necessary. Check
carefully for damage, cuts or excessive wear.Ð
Wheel nutsWhen checking the tires, make sure no nuts are missing, and check for any
loose nuts. Tighten if necessary.Ð
Tire rotationTires should be rotated every 12,000 km (7,500 miles). MA-24
Wheel alignment and
balanceIf the vehicle pulls to either side while driving on a straight and level road, or
if you detect uneven or abnormal tire wear, there may be a need for wheel
alignment. If the steering wheel or seat vibrates at normal highway speeds,
wheel balancing may be needed.MA-24, SU-6, ªFront
Wheel Alignmentº
Windshield wiper
bladesCheck for cracks or wear if they do not wipe properly. Ð
Doors and engine
hoodCheck that all doors and the engine hood operate smoothly as well as the
trunk lid and back hatch. Also make sure that all latches lock securely. Lubri-
cate if necessary. Make sure that the secondary latch keeps the hood from
opening when the primary latch is released.
When driving in areas using road salt or other corrosive materials, check
lubrication frequently.MA-27
INSIDE THE VEHICLE
The maintenance items listed here should be checked on a regular basis, such as when performing periodic maintenance, cleaning the
vehicle, etc.
ItemReference page
LampsMake sure that the headlamps, stop lamps, tail lamps, turn signal lamps, and
other lamps are all operating properly and installed securely. Also check
headlamp aim.Ð
Warning lamps and
buzzers/chimesMake sure that all warning lamps and buzzers/chimes are operating properly. Ð
Windshield wiper
and washerCheck that the wipers and washer operate properly and that the wipers do
not streak.Ð
Windshield defrosterCheck that the air comes out of the defroster outlets properly and in sufficient
quantity when operating the heater or air conditioning.Ð
Steering wheelCheck that it has the specified play. Be sure to check for changes in the
steering condition, such as excessive play, hard steering or strange noises.
Free play: Less than 35 mm (1.38 in)Ð
SeatsCheck seat position controls such as seat adjusters, seatback recliner, etc. to
make sure they operate smoothly and that all latches lock securely in every
position. Check that the head restrains move up and down smoothly and that
the locks (if equipped) hold securely in all latched positions. Check that the
latches lock securely for folding-down rear seatbacks.Ð
Seat beltsCheck that all parts of the seat belt system (e.g. buckles, anchors, adjusters
and retractors) operate properly and smoothly and are installed securely.
Check the belt webbing for cuts, fraying, wear or damage.MA-28, RS-7, ªSeat Belt
Inspectionº
BrakesCheck that the brake does not pull the vehicle to one side when applied. Ð
GENERAL MAINTENANCE
MA-4
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SMA857C
SMA858C
Changing Engine CoolantNBMA0011WARNING:
To avoid the danger of being scalded, never change the cool-
ant when the engine is hot.
ÐDRAINING ENGINE COOLANTÐNBMA0011S011. Set air conditioning system as follows to prevent coolant from
remaining in the system.
a. Turn ignition switch ªONº and set temperature controller to
maximum hot position.
b. Wait 10 seconds before turning ignition switch ªOFFº.
2. Open radiator drain plug at the bottom of radiator.
3. Remove radiator filler cap.
Remove reservoir tank, drain coolant, then clean reservoir
tank.
Install it temporarily.
IBe careful not to allow coolant to contact drive belts.
SMA092D
SMA093D
SMA094DA
4. Open drain plugs on right side of cylinder block and water
pump side, then open air relief plugs to drain coolant.
5. Check drained coolant for contaminants such as rust, coorro-
sion or discoloration. If contaminated flush engine cooling
system, ªRefer to FLUSHING COOLING SYSTEMº, MA-16.
ENGINE MAINTENANCE
Changing Engine Coolant
MA-14