2001 INFINITI QX4 Transfer

6 CHECK INPUT SIGNAL
Without CONSULT-II
1. Start engine (idling).
2. Check voltage between transfer control unit harness connector terminal 4 (or 13) and body ground while 4WD shift
switch is set from 4H to 4LO (or from 4LO to 4H).
SMT836D
3. Result
MTBL0516
OK or NG
OK©GO TO 8.
NG©GO TO 7.
7 CHECK HARNESS CONTINUITY BETWEEN TRANSFER CONTROL UNIT AND TRANSFER CONTROL
DEVICE
OK or NG
OK©GO TO 8.
NG©Repair and replace harness connector between transfer control unit and transfer control
device.
8 PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27.
OK or NG
OK©INSPECTION END
NG©1. Perform transfer control unit/output signal inspection. Refer to ªTRANSFER CON-
TROL UNIT INSPECTION TABLEº, ªTROUBLE DIAGNOSIS Ð GENERAL
DESCRIPTIONº, TF-55.
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with
harness connector.
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SHIFT ACTUATOR CIRCUIT
Diagnostic Procedure (Cont'd)
TF-97

Symptom 1. 4WD Shift Indicator Lamp Does
Not Turn ON
NBTF0029SYMPTOM: Although ignition switch is turned ªONº, all the
4WD shift indicator lamps do not turn ON for 1 second.
1 CHECK TRANSFER CONTROL UNIT POWER SOURCE
SMT958D
SMT860D
1. Turn ignition switch to ªOFFº position and disconnect transfer control unit harness connector.
2. Turn ignition switch to ªONº position. (Do not start engine.)
3. Check voltage between transfer control unit harness connector terminals 16, 22 and body ground.
Voltage: Battery voltage
SMT796D
OK or NG
OK©GO TO 2.
NG©Check the following.
IContinuity between ignition switch and transfer control unit
IIgnition switch and No. 18 fuse (10A)
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 1. 4WD Shift Indicator Lamp Does Not Turn ON
TF-98

2 CHECK TRANSFER CONTROL UNIT GROUND CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect transfer control unit harness connector.
3. Measure resistance between transfer control unit harness connector terminals 6, 45 and body ground.
Resistance: 0W
SMT797D
OK or NG
OK©GO TO 3.
NG©Check continuity between transfer control unit and body ground.
3 CHECK PROCEDURES FROM THE BEGINNING AGAIN
Check again.
OK or NG
OK©INSPECTION END
NG©1. Perform transfer control unit input/output signal inspection. Refer to ªTRANSFER
CONTROL UNIT INSPECTION TABLEº, ªTROUBLE DIAGNOSIS Ð GENERAL
DESCRIPTIONº, TF-55.
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with
harness connector.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 1. 4WD Shift Indicator Lamp Does Not Turn ON (Cont'd)
TF-99

Symptom 2. 4WD Warning Lamp Does Not Turn
ON
=NBTF0030SYMPTOM: Although ignition switch is turned ªONº, 4WD
warning lamp does not turn ON.
1 CHECK TRANSFER CONTROL UNIT POWER SOURCE
SMT799D
1. Turn ignition switch to ªOFFº position and disconnect transfer control unit harness connector.
2. Turn ignition switch to ªONº position.
(Do not start engine.)
3. Check voltage between transfer control unit harness connector terminals 16, 22 and body ground.
Voltage: Battery voltage
SMT800D
OK or NG
OK©GO TO 2.
NG©Check the following.
IContinuity between ignition switch and transfer control unit
IIgnition switch and No. 18 fuse (10A)
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 2. 4WD Warning Lamp Does Not Turn ON
TF-100

2 CHECK TRANSFER CONTROL UNIT GROUND CIRCUIT
1. Turn ignition switch to ªOFFº position.
2. Disconnect transfer control unit harness connector.
3. Measure resistance between transfer control unit harness connector terminals 6, 45 and body ground.
Resistance: 0W
SMT803D
OK or NG
OK©GO TO 3.
NG©Check continuity between transfer control unit and body ground.
3 CHECK 4WD WARNING LAMP CIRCUIT
Check the following.
I4WD warning lamp
IContinuity between ignition switch and 4WD warning lamp
IContinuity between 4WD warning lamp and transfer control unit
OK or NG
OK©GO TO 4.
NG©IRepair or replace harness or connector.
IReplace 4WD warning lamp.
4 CHECK PROCEDURES FROM THE BEGINNING AGAIN
Check again.
OK or NG
OK©INSPECTION END
NG©1. Perform transfer control unit input/output signal inspection. Refer to ªTRANSFER
CONTROL UNIT INSPECTION TABLEº, ªTROUBLE DIAGNOSIS Ð GENERAL
DESCRIPTIONº, TF-55.
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with
harness connector.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 2. 4WD Warning Lamp Does Not Turn ON (Cont'd)
TF-101

Symptom 5. 4LO Indicator Lamp Does Not Turn
ON
=NBTF0033SYMPTOM: When 4WD shift switch is set from ª4Hº to
ª4LOº position, 4LO indicator lamp does not turn ON.
1 CHECK TRANSFER CONTROL UNIT POWER SUPPLY CIRCUIT
SMT958D
SMT851D
SMT979D
1. Disconnect battery negative terminal (þ), then transfer control unit connector.
2. Connect battery negative terminal (þ) and turn ignition switch ªONº (with engine stopped).
3. Check voltage across transfer control unit body-side connector terminals 47, 16 and body ground.
Voltage: Battery voltage
OK or NG
OK©GO TO 2.
NG©Check the following.
IContinuity between battery and transfer control unit
IIgnition switch (Refer to EL-9, ªPower Supply Routingº.)
INo. 24 fuse (7.5A), No. 8 fuse (10A) and No. 18 fuse (10A)
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 5. 4LO Indicator Lamp Does Not Turn ON
TF-104

2 CHECK TRANSFER CONTROL UNIT GROUND CIRCUIT
1. Turn ignition switch ªOFFº, and disconnect transfer control unit connector.
2. Check for continuity between transfer control unit body-side connector terminals 6, 45 and body ground.
Continuity should exist.
OK or NG
OK©GO TO 3.
NG©Check the following.
IContinuity between transfer control unit and body ground
3 CHECK 4LO INDICATOR LAMP CIRCUIT
Disconnect battery negative terminal (þ) and check the following items:
1. Check condition of 4LO indicator lamp.
2. Check continuity between battery and 4LO indicator lamp.
3. Check continuity between 4LO indicator lamp and transfer control unit connector terminal 12.
4. Check condition of ATP switch.
5. Check condition of neutral-4LO switch.
6. Check continuity between neutral-4LO switch ground terminal 6 and body ground.
OK or NG
OK©GO TO 4.
NG©Check the following.
I4LO indicator lamp
INeutral-4LO switch
Refer to ªATP Switch, Neutral-4LO Switch and Wait Detection Switchº, ªCOMPONENT
INSPECTIONº, TF-112.
4 CHECK PROCEDURES FROM THE BEGINNING
Check again.
OK or NG
OK©INSPECTION END
NG©1. Perform transfer control unit input/output signal inspection. Refer to ªTRANSFER
CONTROL UNIT INSPECTION TABLEº, ªTROUBLE DIAGNOSIS Ð GENERAL
DESCRIPTIONº, TF-55.
2. If NG, recheck transfer control unit pin terminals for damage or loose connection with
harness connector.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 5. 4LO Indicator Lamp Does Not Turn ON (Cont'd)
TF-105

Symptom 7. 4WD Shift Indicator Lamp Repeats
Flickering
=NBTF0035SYMPTOM: 4WD shift indicator lamp keeps flickering.
1 CHECK 4WD SHIFT INDICATOR LAMP
SMT958D
1. Set 4WD shift switch to ª2WDº position.
2. Move vehicle forward and backward. Or drive straight increasing or decreasing speed under 20 km/h (12 MPH).
3. Does 4WD shift indicator lamp keep flickering?
YesorNo
Ye s©GO TO 2.
No©INSPECTION END
2 CHECK TIGHT CORNER BRAKING SYMPTOM
Drive vehicle at speed under 20 km/h (12 MPH), turning steering wheel to the limit. Does tight corner braking symptom
occur?
YesorNo
Ye s©GO TO 3.
No©GO TO 4.
3 CHECK 4WD SHIFT INDICATOR LAMP
Does the 4WD shift indicator lamp keep flickering when the front wheels are jacked up?
YesorNo
Ye s©Check transfer unit operating system.
No©Check tires.
4 CHECK 4WD WARNING LAMP
Does 4WD warning lamp flicker? (4WD shift indicator lamp is turned OFF.)
YesorNo
Ye s©Perform self-diagnoses. Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27.
No©GO TO 5.
5 CHECK 4WD SHIFT INDICATOR LAMP
Does 4WD shift indicator lamp keep flickering?
YesorNo
Ye s©Check again.
No©INSPECTION END
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
TROUBLE DIAGNOSES FOR SYMPTOMS
Symptom 7. 4WD Shift Indicator Lamp Repeats Flickering
TF-107