Ac system INFINITI QX4 2001 Factory Service Manual

AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER=NBHA0021S03Without Navigation SystemNBHA0021S0301The trimmer compensates for differences in range of±3ÉC (±6ÉF) between temperature setting (displayed
digitally) and temperature felt by driver.
Operating procedures for this trimmer are as follows:
IBegin Self-diagnosis STEP 5 mode.
IPress
(fan) UP switch to set system in auxiliary mode.
IDisplay shows ª
º in auxiliary mechanism.
It takes approximately 3 seconds.
IPress either
(HOT) or(COLD) switch as desired. Temperature will change at a rate of 0.5ÉC (1ÉF)
each time a switch is pressed.
SHA197E
When battery cable is disconnected, trimmer operation is canceled. Temperature set becomes that of
initial condition, i.e. 0ÉC (0ÉF).
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TROUBLE DIAGNOSES
Self-diagnosis (Cont'd)
HA-53

INTRODUCTION AND GENERAL DESCRIPTIONNBHA0021S04The self-diagnostic system diagnoses sensors, door motors, blower motor, etc. by system line. Refer to appli-
cable sections (items) for details. Shifting from normal control to the self-diagnostic system is accomplished
by starting the engine (turning the ignition switch from ªOFFº to ªONº) and pressing ª
º switch for at least
5 seconds. The ª
º switch must be pressed within 10 seconds after starting the engine (ignition switch is
turned ªONº). This system will be canceled by either pressing
(AUTO) switch or turning the ignition switch
ªOFFº. Shifting from one step to another is accomplished by means of turning temperature dial, as required.
Additionally shifting from STEP 5 to AUXILIARY MECHANISM is accomplished by means of pushing
(fan)
UP switch.
With Navigation SystemNBHA0021S0401
RHA859H
TROUBLE DIAGNOSES
Self-diagnosis (Cont'd)
HA-54

STEP-BY-STEP PROCEDURENBHA0021S05With Navigation SystemNBHA0021S0501
1 SET IN SELF-DIAGNOSTIC MODE
1. Turn ignition switch ON.
2. Set in self-diagnostic mode as follows. Within 10 seconds after starting engine (ignition switch is turned ªONº.), press
switch for at least 5 seconds.
©GO TO 2.
2 STEP 1 - ALL LEDs AND DISPLAY SCREEN ARE CHECKED
When switch's LED and display are functioning properly in STEP-1, LED and display will come on.
RHA860H
OK or NG
OK©GO TO 3.
NG©Malfunctioning
switch, LED or fluorescent display tube.
Go to ªMain Power Supply and Ground Circuit Checkº, HA-72.
3 VERIFY ADVANCE TO SELF-DIAGNOSIS STEP 2
1. Turn temperature dial clockwise.
2. Does advance to self-diagnosis STEP 2?
YesorNo
Ye s©GO TO 4.
No©Malfunctioning temperature dial.
Check Display & NAVI control unit.
4 VERIFY RETURN TO SELF-DIAGNOSIS STEP 1
1. Turn temperature dial counterclockwise.
2. Does return to self-diagnosis STEP 1?
YesorNo
Ye s©GO TO 5.
No©Malfunctioning temperature dial.
Check Display & NAVI control unit.
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TROUBLE DIAGNOSES
Self-diagnosis (Cont'd)
HA-55

13 DETECTS MULTIPLEX COMMUNICATION ERROR
Press REC switch.
Does code No.
appears on the display
MTBL0509
YesorNo
Ye s©INSPECTION END
No©1. Go to ªMultiplex Communication Circuitº, HA-142.
2. Go to ªOPERATIONAL CHECKº, HA-66.
Confirm that A/C system is in good order.
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TROUBLE DIAGNOSES
Self-diagnosis (Cont'd)
HA-61

AUXILIARY MECHANISM: TEMPERATURE SETTING TRIMMER=NBHA0021S06With Navigation SystemNBHA0021S0601The trimmer compensates for differences in range of±3ÉC (±6ÉF) between temperature setting (displayed
digitally) and temperature felt by driver.
Operating procedures for this trimmer are as follows:
IBegin Self-diagnosis STEP 5 mode.
IPress
(fan) UP switch to set system in auxiliary mode.
IDisplay shows ª
º in auxiliary mechanism.
It takes approximately 3 seconds.
ITurn the temperature dial clockwise or counterclockwise: Temperature will change at a rate of 0.5ÉC (1ÉF).
RHA863H
When battery cable is disconnected, trimmer operation is canceled. Temperature set becomes that of
initial condition, i.e. 0ÉC (0ÉF).
TROUBLE DIAGNOSES
Self-diagnosis (Cont'd)
HA-64

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
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TROUBLE DIAGNOSES
How to Perform Trouble Diagnoses for Quick and Accurate Repair
HA-65

Operational CheckNBHA0019The purpose of the operational check is to confirm that the system
operates properly.
CONDITIONS:NBHA0019S01IEngine running and at normal operating temperature.
RHA864H
RHA335HA
PROCEDURE:NBHA0019S021. Check Memory FunctionNBHA0019S02011. Set the temperature 85ÉF or 32ÉC.
2. Press OFF switch.
3. Turn the ignition off.
4. Turn the ignition on.
5. Press the AUTO switch.
6. Confirm that the set temperature remains at previous tempera-
ture.
7. Press OFF switch.
If NG, go to trouble diagnosis procedure for memory function (HA-
126).
If OK, continue with next check.
RHA457GA
RHA329HA
2. Check BlowerNBHA0019S02021. Press fan switch (up side) one time.
Blower should operate on low speed.
The fan symbol should have one blade lit
.
2. Press fan switch (up side) one more time, and continue check-
ing blower speed and fan symbol until all speeds are checked.
3. Leave blower on MAX speed
.
If NG, go to trouble diagnosis procedure for blower motor (HA-95).
If OK, continue with next check.
TROUBLE DIAGNOSES
Operational Check
HA-66

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.
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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