2001 INFINITI QX4 charge

How to Perform Trouble Diagnoses for Quick
and Accurate Repair
=NBHA0018WORK FLOWNBHA0018S01
SHA900E
*1: Operational Check (HA-66)
SYMPTOM TABLENBHA0018S02
Symptom Reference Page
IA/C system does not come on.IGo to Trouble Diagnosis Procedure for A/C system. HA-71
IAir outlet does not change.
IGo to Trouble Diagnosis Procedure for Mode Door Motor. (LAN) HA-75
IMode door motor does not operate nor-
mally.
IDischarge air temperature does not
change.
IGo to Trouble Diagnosis Procedure for Air Mix Door Motor. (LAN) HA-82
IAir mix door motor does not operate nor-
mally.
IIntake door does not change.
IGo to Trouble Diagnosis Procedure for Intake Door Motor. HA-87
IIntake door motor does not operate nor-
mally.
IBlower motor operation is malfunctioning.
IGo to Trouble Diagnosis Procedure for Blower Motor. HA-95
IBlower motor operation is malfunctioning
under out of starting fan speed control.
IMagnet clutch does not engage.IGo to Trouble Diagnosis Procedure for Magnet Clutch. HA-104
IInsufficient cooling.IGo to Trouble Diagnosis Procedure for Insufficient Cooling. HA-112
IInsufficient heating.IGo to Trouble Diagnosis Procedure for Insufficient Heating. HA-121
INoise.IGo to Trouble Diagnosis Procedure for Noise. HA-123
ISelf-diagnosis can not be performed.IGo to Trouble Diagnosis Procedure for Self-diagnosis. HA-124
IMemory function does not operate.IGo to Trouble Diagnosis Procedure for Memory Function. HA-126
IECON mode does not operate.IGo to Trouble Diagnosis Procedure for ECON (ECONOMY) Ð
mode.HA-128
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
How to Perform Trouble Diagnoses for Quick and Accurate Repair
HA-65

RHA865H
RHA330HA
3. Check Discharge AirNBHA0019S02031. Press MODE switch four times and D/F button.
2. Each position indicator should change shape.
RHA654F
3. Confirm that discharge air comes out according to the air dis-
tribution table at left.
Refer to ªDischarge Air Flowº (HA-25).
NOTE:
Confirm that the compressor clutch is engaged (visual inspection)
and intake door position is at FRESH when the DEF
is
selected.
Intake door position is checked in the next step.
If NG, go to trouble diagnosis procedure for mode door motor
(HA-75).
If OK, continue with next check.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Operational Check (Cont'd)
HA-67

RHA459GA
RHA331HA
4. Check RecirculationNBHA0019S02041. Press RECswitch.
Recirculation indicator should illuminate.
2. Listen for intake door position change (you should hear blower
sound change slightly).
If NG, go to trouble diagnosis procedure for intake door (HA-87).
If OK, continue with next check.
RHA460GA
RHA332HA
5. Check Temperature DecreaseNBHA0019S0205Without Navigation System
1) Press the temperature decrease button until 18ÉC (65ÉF) is
displayed.
2) Check for cold air at discharge air outlets.
If NG, go to trouble diagnosis procedure for insufficient cooling
(HA-112).
If OK, continue with next check.
With Navigation System
ITurn the temperature dial counterclockwise until 18ÉC (65ÉF)
is displayed.
ICheck for cold air at discharge air outlets.
If NG, go to trouble diagnosis procedure for insufficient cooling
(HA-112).
If OK, continue with next check.
TROUBLE DIAGNOSES
Operational Check (Cont'd)
HA-68

RHA461GA
SHA278FA
6. Check Temperature IncreaseNBHA0019S0206Without Navigation System
IPress the temperature increase button until 32ÉC (85ÉF) is
displayed.
ICheck for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for insufficient heating
(HA-121).
If OK, continue with next check.
With Navigation System
ITurn the temperature dial clockwise until 32ÉC (85ÉF) is dis-
played.
ICheck for hot air at discharge air outlets.
If NG, go to trouble diagnosis procedure for insufficient heating
(HA-121).
If OK, continue with next check.
RHA462GA
RHA333HA
7. Check ECON (Economy) ModeNBHA0019S02071. Set the temperature 75ÉF or 25ÉC.
2. Press ECON switch.
3. Display should indicate ECON (no AUTO).
Confirm that the compressor clutch is not engaged (visual
inspection).
(Discharge air and blower speed will depend on ambient, in-
vehicle and set temperatures.)
If NG, go to trouble diagnosis procedure for ECON (Economy)
mode (HA-128).
If OK, continue with next check.
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Operational Check (Cont'd)
HA-69

RHA463GA
RHA334HA
8. Check AUTO ModeNBHA0019S02081. Press AUTO switch.
2. Display should indicate AUTO (no ECON).
Confirm that the compressor clutch engages (audio or visual
inspection).
(Discharge air and blower speed will depend on ambient, in-
vehicle and set temperatures.)
If NG, go to trouble diagnosis procedure for A/C system (HA-71),
then if necessary, trouble diagnosis procedure for magnet clutch
(HA-104).
SHA286HA
9. Check Ambient Display (With Navigation System)NBHA0019S02091. Press AUTO switch.
2. Press AMB switch.
3. Display should show the outside (ambient) temperature for
approximately 5 seconds.
If NG, go to trouble diagnosis procedure for multiplex communica-
tion circuit (HA-142).
If all operational check are OK (symptom can not be duplicated),
go to ªIncident Simulation Testsº (GI section) and perform tests as
outlined to simulate driving conditions environment. If symptom
appears, refer to ªSymptom Tableº (HA-65) and perform applicable
trouble diagnosis procedures.
TROUBLE DIAGNOSES
Operational Check (Cont'd)
HA-70

Mode Door Control SpecificationNBHA0052S03
RHA135G
RHA505G
COMPONENT DESCRIPTIONNBHA0053The mode door motor is attached to the heater unit. It rotates so
that air is discharged from the outlet set by the auto amplifier. Motor
rotation is conveyed to a link which activates the mode door.
RHA488GA
DIAGNOSTIC PROCEDURE FOR MODE DOOR MOTOR
AND AIR MIX DOOR MOTOR CIRCUIT
NBHA0104SYMPTOM: Mode door motor and/or air mix door motor does
not operate normally.
TROUBLE DIAGNOSES
Mode Door Motor (Cont'd)
HA-78

Air Mix Door Motor
TROUBLE DIAGNOSIS PROCEDURE FOR AIR MIX DOOR (LAN)=NBHA0098SYMPTOM:
IDischarge air temperature does not change.
IAir mix door motor does not operate.
Inspection FlowNBHA0098S01Without Navigation SystemNBHA0098S0101
SHA246F
*1: HA-44
*2: HA-129
*3: HA-132
*4: HA-135
*5: HA-141*6: STEP-BY-STEP PROCEDURE
(HA-45), see No. 13.
*7: HA-78
*8: HA-85
*9: HA-85*10: HA-66
*12: HA-66
*13: HA-65
*14: HA-139
*15: HA-45
TROUBLE DIAGNOSES
Air Mix Door Motor
HA-82

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