Ignition harness INFINITI QX4 2001 Factory Service Manual

3 CHECK POWER SOURCE OF TRANSFER CONTROL DEVICE
1. Disconnect transfer control device terminal.
2. Turn ignition switch to ªONº. (Do not start engine.)
3. Turn 4WD shift switch from ª4Hº to ª4LOº (or from ª4LOº to ª4Hº).
4. Check voltage between transfer control device terminal 3 (or 4) and body ground.
Voltage: Battery voltage
SMT832D
OK or NG
OK©GO TO 4.
NG©Check the following.
IHarness and connector from transfer shift HI and LOW relays to transfer control
device harness terminal
IGround circuit between transfer control device and body ground.
4 CHECK INPUT SIGNAL
WITH CONSULT-II©GO TO 5.
WITHOUT CONSULT-II©GO TO 6.
GI
MA
EM
LC
EC
FE
AT
PD
AX
SU
BR
ST
RS
BT
HA
SC
EL
IDX
SHIFT ACTUATOR CIRCUIT
Diagnostic Procedure (Cont'd)
TF-95

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

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

Component
partsTerminals Remarks
4WD solenoid
valve6
Ground
terminalApprox. 20ÉC (68ÉF): Approx. 3.0 - 3.4W
Clutch pres-
sure switch7In room temperature
I2-4WD shift solenoid valve ªOFFº: No
continuity
I2-4WD shift solenoid valve and transfer
motor ªONº: Continuity exists
Line pressure
switch1In room temperature
ITurn ignition switch to ªOFFº position
and leave vehicle for more than 5 min-
utes. (OFF): No continuity
ITransfer motor ªONº: Continuity exists
SMT081D
Front Revolution SensorNBTF0038S04Measure resistance between terminals of front revolution sensor
sub-harness connector located on rear-right of transfer unit.
Terminals Resistance
16 - 17 500 - 650W
18 - 17 No continuity
18 - 16 No continuity
SMT806D
Transfer Dropping ResistorNBTF0038S07Check resistance between terminals.
Resistance: 11.2 - 12.8W
SMT083D
ATP Switch, Neutral-4LO Switch and Wait
Detection Switch
NBTF0038S06Measure resistance between terminals of transfer switch assembly
sub-harness connector located on rear-right of transfer unit.
COMPONENT INSPECTION
4WD Solenoid Valve, Clutch Pressure Switch and Line Pressure Switch (Cont'd)
TF-112