Ac system INFINITI QX4 2001 Factory Service Manual

Intake Door Motor
TROUBLE DIAGNOSIS PROCEDURE FOR INTAKE DOOR=NBHA0092SYMPTOM:
IIntake door does not change.
IIntake door motor does not operate normally.
Inspection FlowNBHA0092S01Without Navigation SystemNBHA0092S0101
SHA247F
*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-90
*8: HA-94
*9: HA-66*10: HA-45
*11: HA-66
*12: HA-65
*13: HA-139
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Intake Door Motor
HA-87

With Navigation SystemNBHA0092S0102
RHA873H
*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-90
*8: HA-94
*9: HA-66*10: HA-45
*11: HA-66
*12: HA-65
*13: HA-139
TROUBLE DIAGNOSES
Intake Door Motor (Cont'd)
HA-88

SYSTEM DESCRIPTION=NBHA0056Component PartsNBHA0056S01Intake door control system components are:
1) Auto amp.
2) Intake door motor
3) A/C LAN system (PBR built-in mode motor and air mix door motor)
4) In-vehicle sensor
5) Ambient sensor
6) Sunload sensor
7) Intake sensor
System OperationNBHA0056S02The intake door control determines intake door position based on the ambient temperature, the intake air
temperature and the in-vehicle temperature. When the ECON, DEFROST, or OFF switches are pushed, the
auto amplifier sets the intake door at the ªFreshº position.
RHA874H
Intake Door Control SpecificationNBHA0056S03
RHA136G
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Intake Door Motor (Cont'd)
HA-89

Blower Motor
TROUBLE DIAGNOSIS PROCEDURE FOR BLOWER MOTOR=NBHA0094SYMPTOM:
IBlower motor operation is malfunctioning.
IBlower motor operation is malfunctioning under out of starting fan speed control.
Inspection FlowNBHA0094S01Without Navigation SystemNBHA0094S0101
SHA248FA
*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-98
*8: HA-98
*9: HA-45*10: HA-66
*11: HA-65
*12: HA-66
*13: HA-139
*14: EL-108
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Blower Motor
HA-95

With Navigation SystemNBHA0094S0102
RHA875H
*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-98
*8: HA-98
*9: HA-45*10: HA-66
*11: HA-65
*12: HA-66
*13: HA-139
*14: EL-108
TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-96

SYSTEM DESCRIPTION=NBHA0062Component partsNBHA0062S01Fan speed control system components are:
1) Auto amp.
2) Fan control amp.
3) A/C LAN system (PBR built-in mode door motor and air mix door motor)
4) In-vehicle sensor
5) Ambient sensor
6) Sunload sensor
7) Intake sensor
System OperationNBHA0062S02
SHA006FF
Automatic ModeNBHA0062S03In the automatic mode, the blower motor speed is calculated by the automatic amplifier based on inputs from
the PBR, in-vehicle sensor, sunload sensor, intake sensor and ambient sensor. The blower motor applied
voltage ranges from approximately 5 volts (lowest speed) to 12 volts (highest speed).
The control blower speed (in the range of 5 to 12V), the automatic amplifier supplies a gate voltage to the fan
control amplifier. Based on this voltage, the fan control amplifier controls the voltage supplied to the blower
motor.
Starting Fan Speed ControlNBHA0062S04Start Up From ªCOLD SOAKº Condition (Automatic mode)NBHA0062S0401In a cold start up condition where the engine coolant temperature is below 50ÉC (122ÉF), the blower will not
operate for a short period of time (up to 126 seconds). The exact start delay time varies depending on the
ambient and engine coolant temperature.
In the most extreme case (very low ambient) the blower starting delay will be 126 seconds as described above.
After this delay, the blower will operate at low speed until the engine coolant temperature rises above 55ÉC
(131ÉF), at which time the blower speed will increase to the objective speed.
Start Up From Normal or ªHOT SOAKº Condition (Automatic mode)
NBHA0062S0402The blower will begin operation momentarily after the AUTO button is pushed. The blower speed will gradu-
ally rise to the objective speed over a time period of 3 seconds or less (actual time depends on the objective
blower speed).
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-97

Magnet Clutch
TROUBLE DIAGNOSIS PROCEDURE FOR MAGNET CLUTCH=NBHA0095SYMPTOM:
IMagnet clutch does not engage.
Inspection FlowNBHA0095S01Without Navigation SystemNBHA0095S0101
SHA249F
*1: STEP-BY-STEP PROCEDURE
(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-106
*8: HA-150
*9: HA-155
*10: HA-66*11: HA-45
*12: HA-66
*13: HA-65
*14: HA-139
TROUBLE DIAGNOSES
Magnet Clutch
HA-104

With Navigation SystemNBHA0095S0102
RHA876H
*1: STEP-BY-STEP PROCEDURE
(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-106
*8: HA-150
*9: HA-155
*10: HA-66*11: HA-45
*12: HA-66
*13: HA-65
*14: HA-139
GI
MA
EM
LC
EC
FE
AT
TF
PD
AX
SU
BR
ST
RS
BT
SC
EL
IDX
TROUBLE DIAGNOSES
Magnet Clutch (Cont'd)
HA-105

RHA094GB
SYSTEM DESCRIPTION=NBHA0066Auto amplifier controls compressor operation by ambient tempera-
ture and signal from ECM.
Low Temperature Protection ControlNBHA0066S01Auto amplifier will turn the compressor ªONº or ªOFFº as deter-
mined by a signal detected by ambient sensor.
When ambient temperatures are greater than ±2ÉC (28ÉF), the
compressor turns ªONº. The compressor turns ªOFFº when ambi-
ent temperatures are less than þ5ÉC (23ÉF).
RHA877H
DIAGNOSTIC PROCEDURENBHA0067SYMPTOM: Magnet clutch does not engage when AUTO
switch is ON.
1 CHECK POWER SUPPLY FOR COMPRESSOR
Disconnect compressor harness connector. Do approx. 12 volts exist between compressor harness terminal No. 1 and
body ground?
RHA096G
YesorNo
Ye s©Check magnet clutch coil.
1. If NG, replace magnet clutch. Refer to HA-150.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
4.
Confirm that magnet clutch operation is normal.
No©Disconnect A/C relay. And GO TO 2.
TROUBLE DIAGNOSES
Magnet Clutch (Cont'd)
HA-106

Insufficient Cooling
TROUBLE DIAGNOSIS PROCEDURE FOR INSUFFICIENT COOLING=NBHA0096SYMPTOM:
IInsufficient cooling
Inspection FlowNBHA0096S01Without Navigation SystemNBHA0096S0101
SHA190FC
*1: HA-44
*2: HA-85
*3: HA-116
*4: HA-53
*5: STEP-BY-STEP PROCEDURE
(HA-45), see No. 13.*6: HA-77
*7: HA-89
*8: HA-97
*9: HA-106
*10: HA-114*11: HA-66
*12: HA-45
*13: HA-2
*14: MA-13
*15: LC-20
TROUBLE DIAGNOSES
Insufficient Cooling
HA-112