2001 INFINITI QX4 ECO mode

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

6 CHECK MOTOR OPERATION
Disconnect and reconnect the motor connector and confirm the motor operation.
OK or NG
OK (Return to operate
normally)©Poor contacting the motor connector
NG (Does not operate
normally)©GO TO 7.
7 CHECK MODE DOOR MOTOR OPERATION
1. Disconnect the mode door motor and air mix door motor connector.
2. Reconnect the mode door motor and confirm the motor operation.
OK or NG
OK (Mode door motor
operates normally)©Replace the air mix door motor.
NG (Mode door motor
does not operate nor-
mally)©GO TO 8.
8 CHECK AIR MIX DOOR MOTOR OPERATION
1. Disconnect the mode door motor connector.
2. Reconnect the air mix door motor and confirm the air mix door motor operation.
OK or NG
OK (Air mix door motor
operates normally)©Replace mode door motor.
NG (Air mix door motor
does not operate nor-
mally)©Replace auto amp.
RHA505G
CONTROL LINKAGE ADJUSTMENTNBHA0091Mode DoorNBHA0091S011. Install mode door motor on heater unit and connect it to main
harness.
2. Set up code No. in Self-diagnosis STEP 4. Refer to HA-45.
3. Move side link by hand and hold mode door in DEF mode.
4. Attach mode door motor rod to side link rod holder.
5. Make sure mode door operates properly when changing from
code No.
toby pushing DEF switch.
VENT B/L B/L FOOT D/F DEF
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TROUBLE DIAGNOSES
Mode Door Motor (Cont'd)
HA-81

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
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TROUBLE DIAGNOSES
Intake Door Motor (Cont'd)
HA-89

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).
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TROUBLE DIAGNOSES
Blower Motor (Cont'd)
HA-97

ECON (ECONOMY) Mode
TROUBLE DIAGNOSIS PROCEDURE FOR ECON (ECONOMY) MODE=NBHA0103SYMPTOM:
IECON mode does not operate.
Inspection FlowNBHA0103S01Without Navigation SystemNBHA0103S0101
SHA920EA
*1: HA-72 *2: HA-66 *3: HA-45
TROUBLE DIAGNOSES
ECON (ECONOMY) Mode
HA-128

With Navigation SystemNBHA0103S0102
RHA887H
*1: HA-72 *2: HA-66 *3: HA-45
RHA050G
Ambient Sensor Circuit
COMPONENT DESCRIPTIONNBHA0039The ambient sensor is attached in front of the driver's side con-
denser. It detects ambient temperature and converts it into a resis-
tance value which is then input into the auto amplifier.
AMBIENT TEMPERATURE INPUT PROCESSNBHA0040The automatic amplifier includes a ªprocessing circuitº for the ambi-
ent sensor input. However, when the temperature detected by the
ambient sensor increases quickly, the processing circuit retards the
auto amp. function. It only allows the auto amp. to recognize an
ambient temperature increase of 0.33ÉC (0.6ÉF) per 100 seconds.
As an example, consider stopping for a cup of coffee after high
speed driving. Although the actual ambient temperature has not
changed, the temperature detected by the ambient sensor will
increase. This is because the heat from the engine compartment
can radiate to the front grille area, location of the ambient sensor.
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TROUBLE DIAGNOSES
ECON (ECONOMY) Mode (Cont'd)
HA-129

5. If a leak detector detects a leak, verify at least once by blow-
ing compressed air into area of suspected leak, then repeat
check as outlined above.
6. Do not stop when one leak is found. Continue to check for
additional leaks at all system components.
If no leaks are found, perform steps7-10.
7. Start engine.
8. Set the heater A/C control as follows:
1) A/C switch ON.
2) Face mode
3) Recirculation switch ON
4) Max cold temperature
5) Fan speed high
9. Run engine at 1,500 rpm for at least 2 minutes.
10. Turn engine off and perform leak check again following steps
4 through 6 above.
SHA839E
Refrigerant leaks should be checked immediately after
stopping the engine. Begin with the leak detector at the
compressor. The pressure on the high pressure side will
gradually drop after refrigerant circulation stops and pres-
sure on the low pressure side will gradually rise, as shown
in the graph. Some leaks are more easily detected when
pressure is high.
11. Before connecting ACR4 to vehicle, check ACR4 gauges. No
refrigerant pressure should be displayed. If pressure is
displayed, recover refrigerant from equipment lines and then
check refrigerant purity.
12. Confirm refrigerant purity in supply tank using ACR4 and refrig-
erant identifier.
13. Confirm refrigerant purity in vehicle A/C system using ACR4
and refrigerant identifier.
14. Discharge A/C system using approved refrigerant recovery
equipment. Repair the leaking fitting or component as neces-
sary.
15. Evacuate and recharge A/C system and perform the leak test
to confirm no refrigerant leaks.
16. Conduct A/C performance test to ensure system works
properly.
SERVICE PROCEDURE
Refrigerant Lines (Cont'd)
HA-158

S/VCSW - Wiring diagram ...........................EC-493
Swirl control valve control solenoid
valve .........................................................EC-458
Swirl control valve control vacuum
check switch .............................................EC-493
SWL/V - Wiring diagram ..............................EC-458
Symbols and abbreviations .............................GI-10
Symptom matrix chart...................................EC-118
System readiness test (SRT) code ................EC-61
T
2-4WD shift solenoid valve............................TF-111
Tachometer .....................................................EL-94
Tail lamp ..........................................................EL-61
TAIL/L - Wiring diagram ..................................EL-63
TCM circuit diagram ........................................AT-13
TCM inspection table ......................................AT-92
TFTS - Wiring diagram .................................EC-311
THEFT - Wiring diagram ...............................EL-300
Theft warning system....................................EL-294
Thermometer .................................................EL-110
Thermostat ......................................................LC-16
Three way catalyst function (Left bank) .......EC-347
Three way catalyst function (Right
bank) .........................................................EC-347
Three way catalyst precautions.........................GI-6
Throttle bodies ...............................................EM-12
Throttle position sensor (TPS) .....................EC-174
Throttle position sensor adjustment .............EC-101
Throttle position switch ...........EC-431, AT-184, 264
Tie-rod .............................................................ST-21
Tie-rod ball joints.............................................ST-21
Tightening torque of standard bolts.................GI-50
Timing chain ...................................................EM-20
Tire rotation ....................................................MA-24
Tire size ...........................................................GI-44
TLID - Wiring diagram ..................................EL-179
Tooth contact (front final drive 4WD) .............PD-29
Tooth contact diff. ...........................................PD-56
Torque converter installation .........................AT-278
Torque convertor clutch solenoid
valve ..................................................AT-152, 161
Tow truck towing ..............................................GI-47
Towing point.....................................................GI-49
TP/SW - Wiring diagram ..............................EC-434
TPS - Wiring diagram...................................EC-180
Transfer control unit inspection table..............TF-55
Transfer dropping resistor .............................TF-112
Transfer fluid replacement (Part time
4WD model) ...............................................MA-22
Transfer fluid temperature sensor .................TF-111
Transfer motor ...............................................TF-117
Transfer motor relay ......................................TF-113
Transfer serial number ....................................GI-43
TRANSMT - Wiring diagram .........................EL-325
Tread-FR&RR (Dimensions)............................GI-43
Trim .................................................................BT-28
Trouble diagnoses ...........................................GI-34
Trunk lid opener, electric...............................EL-178Turbine revolution sensor..............................AT-202
TURN - Wiring diagram ..................................EL-77
Turn signal lamp .............................................EL-75
Two trip detection logic ..................................EC-59
Two-pole lift .....................................................GI-47
U
Under body .....................................................BT-60
V
Vacuum cut valve ...........................................EC-32
Vacuum cut valve bypass valve.....EC-32, 585, 591
Vacuum hose (brake system).........................BR-21
Vacuum hose drawing (Engine control) .........EC-26
Valve clearance ..............................................EM-52
Valve guide.....................................................EM-43
Valve seat.......................................................EM-45
Valve spring....................................................EM-46
Vehicle identification number...........................GI-42
Vehicle recovery (freeing a stuck
vehicle) .........................................................GI-49
Vehicle speed sensor (VSS) ........................EC-417
VENT/V - Wiring diagram ............EC-376, 555, 576
Ventilation air filter ........................................HA-159
VIAS .............................................................EC-610
VIAS - Wiring diagram .................................EC-610
Viscosity number (SAE) .................................MA-12
VSS - Wiring diagram ..................................EC-420
W
Wait detection switch ....................................TF-112
WARN - Wiring diagram................................EL-115
Warning chime ..............................................EL-125
Warning lamps ..............................................EL-114
Washer, front .................................................EL-136
Washer, rear..................................................EL-141
Water pump ....................................................LC-12
Water temperature gauge ...............................EL-94
Weatherstrip - See Exterior ............................BT-35
Wheel balance ...............................................MA-24
Wheel bearing (front)........................................AX-4
Wheel bearing (rear) ......................................AX-18
Wheel hub (front)..............................................AX-6
Wheel sensors (ABS)...............................BR-56, 80
Wheel size .......................................................GI-44
Wheelarch height .............................................SU-5
Wheelbase (Dimensions) ................................GI-43
Wide open & closed throttle position
switch ........................................................EC-174
Width (Dimensions) .........................................GI-43
WINDOW - Wiring diagram ..........................EL-245
Window, door ..................................................BT-18
Window, rear side ...........................................BT-55
Window, side - See Rear side window ...........BT-55
ALPHABETICAL INDEX
IDX-8