clutch INFINITI QX4 2001 Factory Service Manual

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

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

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

2 CHECK CIRCUIT CONTINUITY BETWEEN A/C RELAY AND COMPRESSOR
Check circuit continuity between A/C relay harness terminal No. 5 and compressor harness terminal No. 1.
RHA748FB
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 3.
NG©Repair harness or connector.
3 CHECK POWER SUPPLY FOR A/C RELAY
Disconnect A/C relay.
Do approx. 12 volts exist between A/C relay harness terminal Nos. 2, 3 and body ground?
RHA614F
YesorNo
Ye s©GO TO 4.
No©Check power supply circuit and 7.5A (No. 6) fuse at fuse block.
Refer to EL-14, ªWiring Diagram Ð POWER к.
IIf OK, check for open circuit in wiring harness.
Repair or replace as necessary.
IIf NG, replace fuse and check wiring harness for short circuit.
Repair or replace as necessary.
4 CHECK A/C RELAY AFTER DISCONNECTING IT
Refer to HA-110.
OK or NG
OK©Reconnect A/C relay. And GO TO 5.
NG©1. Replace A/C relay.
2. Go to self-diagnosis step-by-step procedure (HA-45) and perform self-diagnosis STEP
4.
Confirm that magnet clutch operation is normal.
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-107

5 CHECK COIL SIDE CIRCUIT OF A/C RELAY
Do approx. 12 volts exist between ECM harness terminal No. 27 and body ground?
RHA482GG
YesorNo
Ye s©GO TO 6.
No©Disconnect A/C relay.
Disconnect ECM harness connector.
GO TO 11.
6 CHECK VOLTAGE FOR ECM
Do approx. 12 volts exist between ECM harness terminal No. 45 and body ground?
RHA701FJ
YesorNo
Ye s©Disconnect ECM harness connector.
Disconnect dual-pressure switch harness connector.
GO TO 7.
No©Check ECM. Refer to EC-127, ªECM Terminals and Reference Valueº.
TROUBLE DIAGNOSES
Magnet Clutch (Cont'd)
HA-108

7 CHECK CIRCUIT CONTINUITY BETWEEN ECM AND AUTO AMP.
Check circuit continuity between ECM harness terminal No. 45 and auto amp. harness terminal No. 22.
RHA878H
Continuity should exist.
If OK, check harness for short.
OK or NG
OK©GO TO 8.
NG©1. Repair harness or connector.
2. Go to ªSTEP-BY-STEP PROCEDUREº, ªSelf-diagnosisº, HA-45 and perform self-diag-
nosis STEP 4.
Confirm that magnet clutch operation is normal.
8 CHECK REFRIGERANT PRESSURE SENSOR
Refer to EC-641, ªDiagnostic Procedureº, HA-111.
OK or NG
OK©GO TO 9.
NG©Replace refrigerant pressure sensor.
9 CHECK VOLTAGE FOR ECM
Check 4.6 volts exist between ECM harness terminal No. 51 and body ground?
RHA482GG
YesorNo
Ye s©Check ECM. Refer to EC-127, ªECM Terminal and Reference Valueº.
No©GO TO 10.
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-109