2005 INFINITI QX4 lock

TROUBLE DIAGNOSIS
TF-39
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Revision: October 20052005 QX56
MOTOR RELAY MON
[ON/OFF]Check signal for transfer
control unit signal output

Accelerator pedal
depressed

Vehicle stopped

Engine running

Brake pedal depressed4WD shift switch: 2WD OFF
4WD shift switch: AUTO
or 4LO (A/T selector lever
“P” or “N” position)OFF
("ON" for approx. 2
sec. after shifting
to “P” and “N”.)
4WD shift switch: AUTO
or 4LO (Except for A/T
selector lever “P” or “N”
position)ON
4WD shift switch: 4H (A/T
selector lever “P” posi-
tion)OFF
("ON" for approx. 2
sec. after shifting
to “P”.)
4WD shift switch: 4H
(Except for A/T selector
lever “P” position)ON
4WD FAIL LAMP [ON/
OFF]Condition of 4WD warn-
ing lamp4WD warning lamp: ON ON
4WD warning lamp: OFF OFF
2WD IND [ON/OFF]Condition of 4WD shift
indicator lamp (2WD
indicator lamp)2WD indicator lamp of 4WD shift indicator lamp: OFF OFF
2WD indicator lamp of 4WD shift indicator lamp: ON ON
AUTO IND [ON/OFF]Condition of 4WD shift
indicator lamp (AUTO
indicator lamp)AUTO indicator lamp of 4WD shift indicator lamp: OFF OFF
AUTO indicator lamp of 4WD shift indicator lamp: ON ON
LOCK IND [ON/OFF]Condition of 4WD shift
indicator lamp (Lock indi-
cator lamp)Lock indicator lamp of 4WD shift indicator lamp: OFF OFF
Lock indicator lamp of 4WD shift indicator lamp: ON ON
4L IND [ON/OFF]Condition of 4LO indica-
tor lamp condition4LO indicator lamp: OFF OFF
4LO indicator lamp: ON ON
AT P I N D [O N / O F F ]Condition of ATP indica-
tor lamp ATP indicator lamp: ON ON
ATP indicator lamp: OFF OFF
SHIFT POS SW1 [ON/
OFF]Condition of actuator
position switch 1
(Low)

Vehicle stopped

Engine running

A/T selector lever “N” posi-
tion

Brake pedal depressed4WD shift switch: 4LO ON
4WD shift switch: 2WD,
AUTO or 4HOFF
SHIFT POS SW2 [ON/
OFF]Condition of actuator
position switch 2
(High)

Vehicle stopped

Engine running

A/T selector lever “N” posi-
tion

Brake pedal depressed4WD shift switch: 4H,
AUTO or 2WDON
4WD shift switch: 4LO OFF
SHIFT ACT1 [ON/OFF]Output condition to actu-
ator motor (High)

Vehicle stopped

Engine running

A/T selector lever “N” posi-
tion

Brake pedal depressed4WD shift switch: 4H to
4LO (“Wait” function is
operating.)ON
Except the above OFF
SHIFT AC MON1 [ON/
OFF]Check signal for transfer
control unit signal output

Vehicle stopped

Engine running

A/T selector lever “N” posi-
tion

Brake pedal depressed4WD shift switch: 4H to
4LO (“Wait” function is
operating.)ON
Except the above OFF Monitored item [Unit] Content Condition Display value

TROUBLE DIAGNOSIS
TF-41
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Revision: October 20052005 QX56
6 B Ground Always 0V
7 L CAN-H — —
8 P CAN-L — —
9G/W4WD shift switch
(2WD)Ignition switch: ON4WD shift switch: 2WD Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
10 L/W Transfer dropping resistor

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch: AUTO 4 - 14V
4WD shift switch: 2WD, 4H or 4LO Less than 1V
11 L4WD shift indicator lamp
(Lock indicator lamp)Lock indicator lamp of 4WD shift indicator lamp: OFF Battery voltage
Lock indicator lamp of 4WD shift indicator lamp: ON 0V
12 W/G 4LO indicator lamp4LO indicator lamp: OFF Battery voltage
4LO indicator lamp: ON 0V
13 G/B Transfer shift low relay

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch: 4LO to 4H (“Wait” func-
tion is operating.)Battery voltage
Except the above 0V
14 LG Transfer motor relay

Accelerator pedal
depressed

Vehicle stopped

Engine running

Brake pedal
depressed4WD shift switch: 2WD Battery voltage
4WD shift switch: AUTO or 4LO (A/T
selector lever “P” or “N” position)Battery voltage
(0V for approx.
2 sec. after
shifting to “P”
and “N”.)
4WD shift switch: AUTO or 4LO (Except
for A/T selector lever “P” or “N” position)0V
4WD shift switch: 4H (A/T selector lever
“P” position)Battery voltage
(0V for approx.
2 sec. after
shifting to “P”.)
4WD shift switch: 4H (Except for A/T
selector lever “P” position)0V
15 L/B ATP warning lampATP indicator lamp: ON 0V
ATP indicator lamp: OFF Battery voltage
16 Y/R Power supplyIgnition switch: ON Battery voltage
Ignition switch: OFF 0V
18 O4WD shift switch
(4H)Ignition switch: ON4WD shift switch: 4H Battery voltage
4WD shift switch: 2WD, AUTO or 4LO 0V
19 LClutch pressure solenoid
valve

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch: AUTO 1.5 - 3V
4WD shift switch: 2WD, 4H or 4LO Less than 1V
21 BR4WD shift indicator lamp
(AUTO indicator lamp)

AUTO indicator lamp of 4WD shift indicator lamp: OFF Battery voltage
AUTO indicator lamp of 4WD shift indicator lamp: ON 0V Te r m i n a lWire
colorItem Condition Data (Approx.)

TROUBLE DIAGNOSIS
TF-47
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Revision: October 20052005 QX56
How to Erase Self-diagnostic Results
1. Perform applicable inspection of malfunctioning item and then repair or replace.
2. Start engine and select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE” on CONSULT-II screen to erase DTC memory.
CAUTION:
If memory cannot be erased, perform applicable diagnosis.
DATA MONITOR MODE
Operation Procedure
1. Perform “CONSULT-II SETTING PROCEDURE”. Refer to TF-44, "CONSULT-II SETTING PROCEDURE"
.
2. Touch “DATA MONITOR”.
3. Select from “SELECT MONITOR ITEM”, screen of data monitor mode is displayed.
NOTE:
When malfunction is detected, CONSULT-II performs REAL-TIME DIAGNOSIS.
Also, any malfunction detected while in this mode will be displayed at real time.
Display Item List
×: Standard –: Not applicable
Monitored item (Unit)Monitor item selection
Remarks
ECU INPUT
SIGNALSMAIN
SIGNALSSELEC-
TION FROM
MENU
VHCL/S SEN·FR [km/h] or [mph]×–×Wheel speed calculated by ABS actuator and
electric unit (control unit).
Signal input with CAN communication line.
VHCL/S SEN·RR [km/h] or [mph]×–×Wheel speed calculated by TCM.
Signal input with CAN communication line.
ENGINE SPEED [rpm]×–×Engine speed calculated by ECM.
Signal input with CAN communication line.
THRTL POS SEN [V]×–×Accelerator pedal position (APP) sensor sig-
nal voltage is displayed.
Signal input with CAN communication line.
FLUID TEMP SE [V]×–×Transfer fluid temperature sensor signal volt-
age is displayed.
BATTERY VOLT [V]×–×Power supply voltage for transfer control unit.
2WD SWITCH [ON/OFF]×–×4WD shift switch status is displayed.
AUTO SWITCH [ON/OFF]×–×4WD shift switch status is displayed.
LOCK SWITCH [ON/OFF]×–×4WD shift switch status is displayed.
(LOCK means 4H of 4WD shift switch.)
4L SW [ON/OFF]×–×4WD shift switch status is displayed.
(4L means 4LO of 4WD shift switch.)
N POSI SW TF [ON/OFF]×–×Neutral-4LO switch signal status is displayed.
ATP SWITCH [ON/OFF]×–×ATP switch signal status is displayed.
WAIT DETCT SW [ON/OFF]×–×Wait detection switch status is displayed.
LINE PRES SW [ON/OFF]×–×Line pressure switch status is displayed.
CL PRES SW [ON / OFF]×–×Clutch pressure switch status is displayed.
N POSI SW AT [ON/OFF]זדN” position signal of A/T PNP switch status
is displayed.
Signal input with CAN communication line.
R POSI SW AT [ON/OFF]זדR” position signal of A/T PNP switch status
is displayed.
Signal input with CAN communication line.

TF-48
TROUBLE DIAGNOSIS
Revision: October 20052005 QX56
P POSI SW AT [ON/OFF]זדP” position signal of A/T PNP switch status is
displayed.
Signal input with CAN communication line.
ABS OPER SW [ON/OFF]×–×ABS operation signal status is displayed.
Signal input with CAN communication line.
VDC OPER SW [ON/OFF]×–×VDC operation signal status is displayed.
Signal input with CAN communication line.
TCS OPER SW [ON/OFF]×–×TCS operation signal status is displayed.
Signal input with CAN communication line.
THROTTLE POSI [0.0/8] –××Thottle position status is displayed.
Signal input with CAN communication line.
4WD MODE [AUTO/LOCK/2WD/4L] –××Control status of 4WD recognized by transfer
control unit. (AUTO, 4H, 2WD or 4LO)
VHCL/S COMP [km/h] or [mph] –××Vehicle speed recognized by transfer control
unit.
COMP CL TORQ [kgm] –××Calculated torque recognized by transfer
control unit.
DUTY SOLENOID [%] –××Control value of clutch pressure solenoid.
2-4WD SOL [ON/OFF] –××Output condition to 2-4WD solenoid.
2-4WD SOL MON [ON/OFF] – –×Check signal for transfer control unit signal
output.
MOTOR RELAY [ON/OFF] –××Transfer motor relay signal status is dis-
played.
MOTOR RELAY MON [ON/OFF] – –×Check signal for transfer control unit signal
output.
4WD FAIL LAMP [ON/OFF] –××Control status of 4WD warning lamp is dis-
played.
2WD IND [ON/OFF] – –×Control status of 4WD shift indicator lamp
(2WD indicator lamp) is displayed.
AUTO IND [ON/OFF] – –×Control status of 4WD shift indicator lamp
(2WD and AUTO indicator lamp) is displayed.
LOCK IND [ON/OFF] – –×Control status of 4WD shift indicator lamp
(2WD, AUTO and Lock indicator) is dis-
played.
4L IND [ON/OFF] – –×Control status of 4LO indicator lamp is dis-
played.
ATP IND [ON/OFF] – –×Control status of ATP warning lamp is dis-
played.
SHIFT POS SW1 [ON/OFF]×–×Actuator position switch 1 (Low) signal status
is displayed.
SHIFT POS SW2 [ON/OFF]×–×Actuator position switch 2 (high) signal status
is displayed.
SHIFT ACT1 [ON/OFF] –××Output condition to actuator motor (clock-
wise)
SHIFT AC MON1 [ON/OFF]×–×Check signal for transfer control unit signal
output
SHIFT ACT2 [ON/OFF] –××Output condition to actuator motor (counter-
clockwise)
SHIFT AC MON2 [ON/OFF]×–×Check signal for transfer control unit signal
output Monitored item (Unit)Monitor item selection
Remarks
ECU INPUT
SIGNALSMAIN
SIGNALSSELEC-
TION FROM
MENU

TROUBLE DIAGNOSIS
TF-51
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Revision: October 20052005 QX56
Diagnostic Procedure
1. Warn up engine.
2. Move A/T selector lever to “P” position.
3. Turn 4WD shift switch to “2WD” position.
4. Turn ignition switch “ON” and “OFF” at least twice, and then turn ignition switch “OFF”.
5. Turn 4WD shift switch to “AUTO” position.
6. Turn ignition switch “ON”. (Do not start engine.)
7. 4WD warning lamp ON.
If 4WD warning lamp does not turn ON, refer to TF-121, "
4WD Warning Lamp Does Not Turn ON" .
8. Move A/T selector lever to “R” position.
9. Turn 4WD shift switch to “2WD”, “AUTO” and “2WD” in order.
10. Move A/T selector lever to “D” position.
11. Turn 4WD shift switch to “LOCK”, “AUTO” and “LOCK” in order.
12. Move A/T selector lever to “N” position.
13. Turn 4WD shift switch to “AUTO” position.
14. Move A/T selector lever to “P” position.
15. Read the flickering of 4WD warning lamp.
Refer to TF-51, "
Judgement Self-diagnosis" .
Judgement Self-diagnosis
When a malfunction is detected, the malfunction route is indicated by flickering of the 4WD warning lamp.
PDIA0227E
Flickering pattern or
flickering conditionItems Malfunction Check items
2Output shaft revolution
signal (from TCM)

Malfunction is detected in output shaft revolution signal
that is output from TCM through CAN communication.

Improper signal is input while driving.TF-58, "
Output Shaft
Revolution Signal
(TCM)"
3Clutch pressure sole-
noid signal
Proper voltage is not applied to clutch pressure solenoid
valve due to open or short circuit.TF-86, "Clutch Pres-
sure Solenoid"
4 2-4WD solenoid signal
Proper voltage is not applied to 2-4WD solenoid valve
due to open or short circuit.TF-91, "2-4WD Sole-
noid"
5 Transfer motor
Motor does not operate properly due to open or short cir-
cuit in transfer motor or motor relay.TF-95, "Tran s fe r Mo to r"
6Vehicle speed signal
(from ABS)

Malfunction is detected in vehicle speed signal that is
output from ABS actuator and electric unit (control unit)
through CAN communication.

Improper signal is input while driving.TF-58, "
Vehicle Speed
Sensor (ABS)"
7 CAN communication
Malfunction has been detected from CAN communica-
tion line.TF-113, "CAN Commu-
nication Line"
8 AD converter
AD converter system of transfer control unit is malfunc-
tioning.TF-54, "Power Supply
Circuit For Transfer
Control Unit"

TF-62
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect neutral-4LO switch harness connector.
3. Remove neutral-4LO switch. Refer to TF-22, "
Location of Electrical Parts" .
4. Push and release neutral-4LO switch and check continuity
between neutral-4LO switch terminals 12 and 13.
5. If NG, replace the neutral-4LO switch. Refer to TF-22, "
Location
of Electrical Parts" .
4WD Shift SwitchEDS0 02 I9
CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE
Data are reference value.
TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE
Data are reference value and are measured between each terminal and ground.
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.Terminal Condition Continuity
12 - 13Push neutral-4LO switch Yes
Release neutral-4LO switch No
SDIA2696E
Monitored item [Unit] Content Condition Display value
2WD SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: 2WD ON
4WD shift switch: AUTO, 4H or 4LO OFF
AUTO SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: AUTO ON
4WD shift switch: 2WD, 4H or 4LO OFF
LOCK SWITCH [ON/
OFF]Input condition from 4WD
shift switch4WD shift switch: 4H ON
4WD shift switch: 2WD, AUTO or 4LO OFF
4L SWITCH [ON/OFF]Input condition from 4WD
shift switch4WD shift switch: 4LO ON
4WD shift switch: 2WD, AUTO or 4H OFF
4WD MODE [AUTO/
LOCK/2WD/4L]Control status of 4WD
(Output condition of 4WD
shift indicator lamp and
4LO indicator lamp)

Vehicle stopped

Engine running

A/T selector lever “N”
position

Brake pedal depressed4WD shift switch: 2WD 2WD
4WD shift switch: AUTO AUTO
4WD shift switch: 4H LOCK
4WD shift switch: 4LO 4L
Te r m i n a lWire
colorItem Condition Data (Approx.)
9G/W4WD shift switch
(2WD)Ignition switch: ON4WD shift switch: 2WD Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
18 O4WD shift switch
(4H)Ignition switch: ON4WD shift switch: 4H Battery voltage
4WD shift switch: 2WD, AUTO or 4LO 0V
23 R4WD shift switch
(4LO)Ignition switch: ON4WD shift switch: 4LO Battery voltage
4WD shift switch: 2WD, AUTO or 4H 0V
24 LG/R4WD shift switch
(AUTO)Ignition switch: ON4WD shift switch: AUTO Battery voltage
4WD shift switch: 2WD, 4H or 4LO 0V

TROUBLE DIAGNOSIS FOR SYSTEM
TF-63
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Revision: October 20052005 QX56
DIAGNOSTIC PROCEDURE
1. CHECK 4WD SHIFT SWITCH SIGNAL
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out ON/OFF switching action of the “2WD SWITCH”,
“AUTO SWITCH”, “LOCK SWITCH”, “4L SWITCH” with operat-
ing 4WD shift switch.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Check voltage between transfer control unit harness connector
terminals and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
SDIA2697E
ConnectorTe r m i n a l
(Wire color)ConditionVoltage
(Approx.)
E1429 (G/W) -
ground4WD shift switch: 2WD Battery voltage
4WD shift switch: AUTO, 4H or 4LO 0V
18 (O) -
ground4WD shift switch: 4H Battery voltage
4WD shift switch: 2WD, AUTO or
4LO 0V
23 (R) -
ground4WD shift switch: 4LO Battery voltage
4WD shift switch: 2WD, AUTO or
4H 0V
24 (LG/R) -
ground4WD shift switch: AUTO Battery voltage
4WD shift switch: 2WD, 4H or 4LO 0V
WDIA0148E

TF-72
TROUBLE DIAGNOSIS FOR SYSTEM
Revision: October 20052005 QX56
OK or NG
OK >> GO TO 7.
NG >> GO TO 2.
2. CHECK ACTUATOR MOTOR POWER SUPPLY CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shift high relay and transfer shift low relay.
3. Check voltage between transfer shift high relay harness connec-
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
4. Turn ignition switch “ON”. (Do not start engine.)
5. Check voltage between transfer shift high relay harness connec-
tor E46 terminal 5 (R), transfer shift low relay harness connector
E47 terminal 5 (R) and ground.
OK or NG
OK >> GO TO 3.
NG >> Check the following. If any items are damaged, repair or
replace damaged parts.

20A fuse [No. 57, located in the fuse block (J/B)]. Refer to PG-4, "POWER SUPPLY ROUTING
CIRCUIT" .

Harness for short or open between battery, transfer shift high relay harness connector terminal
5 and transfer shift low relay harness connector terminal 5.
E14333 (R/L) -
Ground

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch: 4H
to 4LO (“Wait” function
is operating.)Battery
voltage
Except the above 0V
42 (P/G)
- Ground

Vehicle stopped

Engine running

A/T selector lever
“N” position

Brake pedal
depressed4WD shift switch: 4LO
to 4H (“Wait” function
is operating.)Battery
voltage
Except the above 0V ConnectorTe r m i n a l
(Wire
color)ConditionVoltage
(Approx.)
Connector Terminal (Wire color) Voltage (Approx.)
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground
SDIA2707E
Connector Terminal (Wire color) Voltage (Approx.)
E46 5 (R) - Ground
Battery voltage
E47 5 (R) - Ground
SDIA2706E