fuse INFINITI QX4 2001 Factory Service Manual

System DescriptionNBSC0009The alternator provides DC voltage to operate the vehicle's electrical system and to keep the battery charged.
The voltage output is controlled by the IC regulator.
Power is supplied at all times to alternator terminal S through:
I120A fusible link (lettera, located in the fuse and fusible link box), and
I7.5A fuse (No. 65, located in the fuse and fusible link box).
Terminal B supplies power to charge the battery and operate the vehicle's electrical system. Output voltage
is controlled by the IC regulator at terminal S detecting the input voltage. The charging circuit is protected by
the 120A fusible link.
Terminal E of the alternator supplies ground through body ground E101.
With the ignition switch in the ON or START position, power is supplied
Ithrough 10A fuse [No. 8, located in the fuse block (J/B)]
Ito combination meter terminal 12 for the charge warning lamp.
Ground is supplied to terminal 43 of the combination meter through terminal L of the alternator. With power
and ground supplied, the charge warning lamp will illuminate. When the alternator is providing sufficient volt-
age with the engine running, the ground is opened and the charge warning lamp will go off.
If the charge warning lamp illuminates with the engine running, a fault is indicated.GI
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CHARGING SYSTEM
System Description
SC-19

DIAGNOSTIC PROCEDURE 1NBSC0020S03Check ªLº Terminal CircuitNBSC0020S0301
1 CHECK ªLº TERMINAL CONNECTION
Check to see if ªLº terminal is clean and tight.
OK or NG
OK©GO TO 2.
NG©Repair ªLº terminal connection. Confirm repair by performing complete Battery/Starting/
Charging system test.
2 CHECK ªLº TERMINAL CIRCUIT
1. Disconnect E106 connector from alternator.
2. Apply ground to E106 connector terminal 1 with the ignition switch in the ON position.
SEL424X
OK or NG
OK©Replace the alternator. Confirm repair by performing complete Battery/Starting/Charging
system test.
NG©Check the following.
I10A fuse [No. 8, located in fuse block (J/B)]
ICHARGE lamp
IHarness for open or short between combination meter and fuse
IHarness for open or short between combination meter and alternator
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CHARGING SYSTEM
Trouble Diagnoses with Battery/Starting/Charging System Tester (Cont'd)
SC-25

DIAGNOSTIC PROCEDURE 2=NBSC0020S04Check ªBº Terminal CircuitNBSC0020S0401
1 CHECK ªBº TERMINAL CONNECTION
Check to see if ªBº terminal is clean and tight.
OK or NG
OK©GO TO 2. Confirm repair by performing complete Battery/Starting/Charging system test.
NG©Repair ªBº terminal connection.
2 CHECK ALTERNATOR ªBº TERMINAL CIRCUIT
Check voltage between alternator terminal B and ground using a digital circuit tester.
SEL425X
OK or NG
OK©GO TO 3.
NG©Check the following.
I120A fusible link (lettera, located in fuse and fusible link box)
IHarness for open or short between alternator and fusible link
3 CHECK ªBº TERMINAL CONNECTION QUALITY (VOLTAGE DROP TEST)
Check voltage between alternator terminal B and battery positive terminal using a digital tester.
SEL426X
OK or NG
OK©Replace the alternator. Confirm repair by performing complete Battery/Starting/Charging
system test.
NG©Check harness between the battery and the alternator for poor continuity.
CHARGING SYSTEM
Trouble Diagnoses with Battery/Starting/Charging System Tester (Cont'd)
SC-26

DIAGNOSTIC PROCEDURE 3=NBSC0020S05Check ªSº Terminal CircuitNBSC0020S0501
1 CHECK ªSº TERMINAL CONNECTION
Check to see if ªSº terminal is clean and tight.
OK or NG
OK©GO TO 2.
NG©Repair ªSº terminal connection. Confirm repair by performing complete Battery/Starting/
Charging system test.
2 CHECK ALTERNATOR ªSº TERMINAL CIRCUIT
Check voltage between alternator terminal 2 and ground using a digital circuit tester.
SEL427X
OK or NG
OK©GO TO 3.
NG©Check the following.
I7.5A fuse (No. 65, located in fuse and fusible link box)
IHarness for open or short between alternator and fuse
3 CHECK ªSº TERMINAL CONNECTION QUALITY (VOLTAGE DROP TEST)
Check voltage between alternator terminal 2 and battery positive terminal using a digital tester.
SEL428X
OK or NG
OK©Replace the alternator. Confirm repair by performing complete Battery/Starting/Charging
system test.
NG©Check harness between the battery and the alternator for poor continuity.
MALFUNCTION INDICATORNBSC0020S06The IC regulator warning function activates to illuminate
ªCHARGEº warning lamp, if any of the following symptoms occur
while alternator is operating:
IExcessive voltage is produced.
INo voltage is produced.
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CHARGING SYSTEM
Trouble Diagnoses with Battery/Starting/Charging System Tester (Cont'd)
SC-27

3 CHECK 4WD SHIFT SWITCH POWER SOURCE
1. Disconnect 4WD shift switch harness connector.
2. Turn ignition switch to ªONº position.
3. Check voltage between 4WD shift switch harness connector terminal 1 and body ground.
Voltage: Battery voltage
SMT852D
OK or NG
OK©GO TO 4.
NG©Check the following.
INo. 18 fuse (10A)
IContinuity between ignition switch and 4WD shift switch
2-4WD SHIFT SOLENOID VALVE AND 4WD SHIFT SWITCH
Diagnostic Procedure (Cont'd)
TF-68

4 CHECK TRANSFER MOTOR RELAY POWER SOURCE
1. Disconnect transfer motor relay harness connector.
2. Turn ignition switch to ªONº position.
3. Check voltage between transfer motor relay harness connector terminals 1, 3 and body ground.
Voltage: Battery voltage
SMT854DA
OK or NG
OK©GO TO 5.
NG©Check the following.
INo. 55 fuse (20A)
INo. 18 fuse (10A)
IHarness continuity between fuse and transfer motor relay
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TRANSFER MOTOR AND TRANSFER MOTOR RELAY
Diagnostic Procedure (Cont'd)
TF-71

Diagnostic ProcedureNBTF0028
1 CHECK TRANSFER CONTROL UNIT POWER SOURCE
1. Turn ignition switch to ªOFFº position and perform self-diagnosis again.
Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27 and ªTrouble Diagnosis with CONSULT-IIº, TF-30.
2. Turn ignition switch to ªOFFº position.
3. Disconnect transfer control unit harness connector.
4. Check voltage between transfer control unit harness connector terminal 47 and body ground.
Voltage: Battery voltage
SMT794D
OK or NG
OK©GO TO 2.
NG©Check the following.
INo. 24 fuse (7.5A)
IHarness continuity between fuse and transfer control unit
2 PERFORM SELF-DIAGNOSIS AGAIN
After driving for a while, perform self-diagnosis again.
Refer to ªTrouble Diagnosis without CONSULT-IIº, TF-27 and ªTrouble Diagnosis with CONSULT-IIº, TF-30.
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.
DATA ERASE/DISPLAY
Diagnostic Procedure
TF-88

Diagnostic ProcedureNBTF0064
1 SHIFT ACTUATOR
Refer to ªActuator & Actuator Position Switchº, ªCOMPONENT INSPECTIONº, TF-115.
OK or NG
OK©GO TO 3.
NG©GO TO 2.
2 CHECK POWER SOURCE
SMT825DA
1. Disconnect transfer control device terminal.
2. Turn ignition switch to ªONº. (Do not start engine.)
3. Check voltage between transfer control device harness connector 3 (or 4) and body ground while 4WD shift switch is
set from 4H to 4LO (or from 4LO to 4H).
Voltage: Battery voltage
OK or NG
OK©Repair or replace actuator.
NG©1. Recheck the following.
IContinuity between ignition switch and transfer HI & LOW relays
IIgnition switch and No. 3 fuse (20A)
IContinuity between transfer shift HI & LOW relays and transfer control device
2. If NG, repair or replace damaged part.
3 CHECK INPUT SIGNAL
WITH CONSULT-II©GO TO 4.
WITHOUT CONSULT-II©GO TO 5.
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SHIFT ACTUATOR
Diagnostic Procedure
TF-89

Diagnostic ProcedureNBTF0066
1 SHIFT ACTUATOR CIRCUIT
Refer to ªTransfer Shift Relay (High & Low)º, ªCOMPONENT INSPECTIONº and ªActuator & Actuator Position Switchº,
ªCOMPONENT INSPECTIONº, TF-114, 115.
OK or NG
OK©GO TO 2.
NG©Repair or replace transfer shift relay and actuator and actuator position switch.
2 CHECK POWER SOURCE OF TRANSFER SHIFT (HI & LOW) RELAY
SMT825DA
1. Disconnect transfer control device terminal.
2. Turn ignition switch to ªONº (Do not start engine).
3. Check voltage between transfer shift HI and LOW relay terminal 5 and body ground.
Voltage: Battery voltage
SMT831D
OK or NG
OK©GO TO 3.
NG©Check the following.
IContinuity between ignition switch and transfer shift HI & LOW relays
ICheck ground circuit between transfer shift HI & LOW relays and body ground.
IIgnition switch and No. 3 fuse (20A)
SHIFT ACTUATOR CIRCUIT
Diagnostic Procedure
TF-94

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