2007 INFINITI QX56 ignition

TF-42
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
CAUTION:
When using a circuit tester to measure voltage for inspection, be sure not to extend forcibly any connector terminals.
CONSULT-II Function (ALL MODE AWD/4WD)INFOID:0000000003532527
FUNCTION
CONSULT-II can display each diagnostic item using the diagnostic test modes shown following.
41 RTransfer motor relay moni-
tor• Accelerator pedal
depressed
• Vehicle stopped
• Engine running
• Brake pedal de-
pressed4WD shift switch: 2WD 0V
4WD shift switch: AUTO or 4LO (A/T selec-
tor lever “P” or “N” position)0V
(Battery volt-
age 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)Battery voltage
4WD shift switch: 4H (A/T selector lever
“P” position)0V
(Battery volt-
age for approx.
2 sec. after
shifting to “P”.)
4WD shift switch: 4H (Except for A/T selec-
tor lever “P” position)Battery voltage
42 P/GTransfer shift low relay
monitor• Vehicle stopped
• Engine running
• A/T selector lever
“N” position
• Brake pedal de-
pressed4WD shift switch: 4LO to 4H (“Wait” func-
tion is operating.)Battery voltage
Except the above 0V
43 G/Y Wait detection switch• Vehicle stopped
• Engine running
• A/T selector lever
“N” position
• Brake pedal de-
pressed4WD shift switch: 2WD, AUTO or 4H Battery voltage
4WD shift switch: 4H to 4LO (While actua-
tor motor is operating.)Battery voltage
→ 0V
4WD shift switch: 4LO to 4H (While actua-
tor motor is operating.)0V → Battery
voltage
4WD shift switch: 4LO 0V
44 LG/BActuator position switch 1
(Low)• Vehicle stopped
• Engine running
• A/T selector lever
“N” position
• Brake pedal de-
pressed4WD shift switch: 4LO 0V
4WD shift switch: 2WD, AUTO or 4H Battery voltage
45 B Ground Always 0V
47 WPower supply
(Memory back-up)Ignition switch: ON Battery voltage
Ignition switch: OFF Battery voltage Te r m i n a lWire
colorItem Condition Data (Approx.)
ALL MODE AWD/4WD diag-
nostic modeDescription
SELF-DIAG RESULTS Displays transfer control unit self-diagnosis results.
DATA MONITOR Displays transfer control unit input/output data in real time.
WORK SUPPORTSupports inspections and adjustments. Commands are transmitted to the transfer control unit for set-
ting the status suitable for required operation, input/output signals are received from the transfer control
unit and received data is displayed.
CAN DIAG SUPPORT MNTR The results of transmit/receive diagnosis of CAN communication can be read.
ECU PART NUMBER Transfer control unit part number can be read.

TROUBLE DIAGNOSIS
TF-43
< SERVICE INFORMATION >
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CONSULT-II START PROCEDURE
Refer to GI-36, "CONSULT-II Start Procedure" .
SELF-DIAG RESULT MODE
Operation Procedure
1. Perform “CONSULT-II Start Procedure”. Refer to GI-36, "CONSULT-II Start Procedure".
2. With engine at idle, touch “SELF-DIAG RESULTS”.
Display shows malfunction experienced since the last erasing
operation.
NOTE:
•The details for “TIME” are as follow:
-“0”: Error currently detected with transfer control unit.
-Except for “0”: Error detected in the past and memorized
with transfer control unit.
Detects frequency of driving after DTC occurs (frequency
of turning ignition switch “ON/OFF”).
Display Item List
SDIA2687E
Items (CONSULT-II screen
terms)Diagnostic item is detected when... Check item
CONTROL UNIT 1
[P1802]• Malfunction is detected in the memory (RAM) system of transfer
control unit.TF-53, "
Transfer Control Unit"
CONTROL UNIT 2
[P1803]• Malfunction is detected in the memory (ROM) system of transfer
control unit.TF-53, "Transfer Control Unit"
CONTROL UNIT 3
[P1804]• Malfunction is detected in the memory (EEPROM) system of trans-
fer control unit.TF-53, "Transfer Control Unit"
VHCL SPEED SEN·AT
[P1807]• Malfunction is detected in output shaft revolution signal that is out-
put from TCM through CAN communication.
• Improper signal is input while driving.TF-53, "Output Shaft Revolution
Signal (TCM)"
VHCL SPEED SEN·ABS
[P1808]• Malfunction is detected in vehicle speed signal that is output from
ABS actuator and electric unit (control unit) through CAN commu-
nication.
• Improper signal is input while driving.TF-54, "Vehicle Speed Sensor
(ABS)"
CONTROL UNIT 4
[P1809]• AD converter system of transfer control unit is malfunctioning.TF-53, "Transfer Control Unit"
4L POSI SW TF
[P1810]• Improper signal from neutral-4LO switch is input due to open or
short circuit.TF-54, "Neutral-4LO Switch"
BATTERY VOLTAGE
[P1811]• Power supply voltage for transfer control unit is abnormally low
while driving.TF-51, "Power Supply Circuit for
Transfer Control Unit"
4WD MODE SW
[P1813]• More than two switch inputs are simultaneously detected due to
short circuit of 4WD shift switch.TF-57, "4WD Shift Switch"
4WD DETECT SWITCH
[P1814]• Improper signal from wait detection switch is input due to open or
short circuit.TF-60, "Wait Detection Switch"
PNP SW/CIRC
[P1816]• When A/T PNP switch signal is malfunction or communication er-
ror between the vehicles.TF-63, "PNP Switch Signal
(TCM)"
SHIFT ACTUATOR
[P1817]• Motor does not operate properly due to open or short circuit in ac-
tuator motor.
• Malfunction is detected in the actuator motor. (When 4WD shift
switch is operated and actuator motor is not operated)
• Malfunction is detected in transfer shift high relay and transfer shift
low relay.TF-64, "Actuator Motor"
SHIFT ACT POSI SW
[P1818]• Improper signal from actuator position switch is input due to open
or short circuit.
• Malfunction is detected in the actuator position switch.TF-69, "Actuator Position Switch"

TF-48
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
4. When clutch force release limit value is set to “1.2 kgm”, current
value “0.3 kgm” shown on display will be replaced by “1.2 kgm”
and “ADJUSTMENT COMPLETE” will appear at the same time.
Clutch force release limit value setting is now complete.
Self-Diagnosis ProcedureINFOID:0000000003532528
SELF-DIAGNOSTIC PROCEDURE (WITH CONSULT-II)
Refer to TF-42, "CONSULT-II Function (ALL MODE AWD/4WD)" .
SELF-DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-II)
Description
If the engine starts when there is something wrong with the 4WD system, the 4WD warning lamp turns ON or
flickers in the combination meter. When the system functions properly, the warning lamp turns ON when the
ignition switch is turned to “ON”, and it turns OFF after engine starts. To locate the cause of a problem, start
the self-diagnosis function. The 4WD warning lamp in the combination meter will indicate the problem area by
flickering according to the self-diagnostic results. As for the details of the 4WD warning lamp flickering pat-
terns, refer to "Diagnostic Procedure".
Diagnostic Procedure
1. Warm 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-104, "
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 “4H”, “AUTO” and “4H” 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 "Judgement Self-diagnosis".
Judgement Self-diagnosis
When a malfunction is detected, the malfunction route is indicated by flickering of the 4WD warning lamp.
SMT970D

TF-50
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
CAUTION:
• If “CAN communication” is displayed with other DTCs, first perform the trouble diagnosis for CAN communication line.
• If “ABS operation signal”, “VDC operation signal" or “TCS operation signal" is displayed, first perform the trouble diagnosis
for ABS system.
• If “Output shaft revolution signal” is displayed, first perform the trouble diagnosis for A/T system.
NOTE:
• If "actuator position switch" or “actuator circuit” is displayed, first erase self-diagnostic results. ("Actuator position switch" or “actuator
circuit” may be displayed after installing transfer control unit or transfer assembly.)
• If “clutch pressure switch” or “line pressure switch” is displayed only while driving in reverse, check the continuity of “R” position on A/
T PNP switch. When there is nothing wrong with the electrical system, check the hydraulic system.
ERASE SELF-DIAGNOSIS
• In order to make it easier to find the cause of hard-to-duplicate malfunctions, malfunction information is
stored into the control unit as necessary during use by the user. This memory is not erased no matter how
many times the ignition switch is turned ON and OFF.
• However, this information is erased by turning ignition switch “OFF” after performing self-diagnostics or by
erasing the memory using the CONSULT-II.
17ABS operation signal
(from ABS)• Malfunction is detected in ABS operation signal that is
output from ABS actuator and electric unit (control unit)
through CAN communication.TF-97, "ABS Operation
Signal (ABS)"
18 Wait detection switch• Improper signal from wait detection switch is input due to
open or short circuit.TF-60, "Wait Detection
Switch"
19 Actuator motor• Motor does not operate properly due to open or short cir-
cuit in actuator motor.
• Malfunction is detected in the actuator motor. (When
4WD shift switch is operated and actuator motor is not
operated)
• Malfunction is detected in transfer shift high relay and
transfer shift low relay.TF-64, "
Actuator Motor",
TF-51, "
Power Supply
Circuit for Transfer Con-
trol Unit"
20Actuator position
switch• Improper signal from actuator position switch is input due
to open or short circuit.
• Malfunction is detected in the actuator position switch.TF-69, "Actuator Posi-
tion Switch"
21 Actuator circuit• Transfer control device actuator circuit is shorted or open.
(Malfunctions are detected when motor relay circuit is
open/shorted or relay transfer shift circuit is open/short-
ed.)
• Malfunction occurs in transfer control device drive circuit.TF-72, "
Transfer Control
Device"
• Malfunction is detected in transfer shut off relay.TF-51, "
Power Supply
Circuit for Transfer Con-
trol Unit"
22VDC operation signal
(from VDC)• Malfunction is detected in VDC operation signal that is
output from ABS actuator and electric unit (control unit)
through CAN communication.TF-98, "VDC Operation
Signal (ABS)"
23TCS operation signal
(from TCS)• Malfunction is detected in TCS operation signal that is
output from ABS actuator and electric unit (control unit)
through CAN communication.TF-98, "TCS Operation
Signal (ABS)"
24PNP switch signal
(from TCM)• When A/T PNP switch signal is malfunctioning or commu-
nication error between the vehicles.TF-63, "PNP Switch
Signal (TCM)"
Repeats flickering
every 2 to 5 sec.— Circuits that the self-diagnosis covers have no malfunction. —
Repeats flickering
every 0.25 sec.Data erase display• Power supply failure of memory back-up.
• Battery performance is poor.TF-51, "
Power Supply
Circuit for Transfer Con-
trol Unit"
No flickeringPNP switch or 4WD
shift switch• PNP switch or 4WD shift switch circuit is shorted or open.TF-63, "
PNP Switch
Signal (TCM)", TF-57,
"4WD Shift Switch"
Flickering pattern or
flickering conditionItems Malfunction Check items

TROUBLE DIAGNOSIS FOR SYSTEM
TF-51
< SERVICE INFORMATION >
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TROUBLE DIAGNOSIS FOR SYSTEM
Power Supply Circuit for Transfer Control UnitINFOID:0000000003532529
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.
DIAGNOSTIC PROCEDURE
1.CHECK POWER SUPPLY
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Connect transfer control unit harness connector.
3. Check voltage between transfer control unit harness connector
terminals and ground.
Monitored item [Unit] Content Condition Display value
BATTERY VOLT [V]Power supply voltage for
transfer control unitIgnition switch: ON Battery voltage
Te r m i n a lWire
colorItem Condition Data (Approx.)
3 B Ground Always 0V
6 B Ground Always 0V
16 Y/R Power supplyIgnition switch: ON Battery voltage
Ignition switch: OFF
(5 seconds after Ignition switch is turned OFF) 0V
22 Y/R Power supplyIgnition switch: ON Battery voltage
Ignition switch: OFF
(5 seconds after Ignition switch is turned OFF) 0V
29 L/W Ignition switch monitorIgnition switch: ON Battery voltage
Ignition switch: OFF 0V
30 SB Shut off relayIgnition switch: ON 0V
Ignition switch: OFF
(5 seconds after Ignition switch is turned OFF)Battery voltage
45 B Ground Always 0V
47 WPower supply
(Memory back-up)Ignition switch: ON Battery voltage
Ignition switch: OFF Battery voltage
Connector Terminal Voltage (Approx.)
E14216 - Ground
0V 22 - Ground
E14329 - Ground
30 - Ground
Battery voltage
47 - Ground
WDIA0165E

TF-52
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS FOR SYSTEM
4. Turn ignition switch “ON”. (Do not start engine.)
5. Check voltage between transfer control unit harness connector
terminals and ground.
OK or NG
OK >> GO TO 2.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
• 10A fuses No. 26 located in fuse and fusible link box and No. 59 located in the fuse and relay
box. Refer to PG-3
.
• 20A fuse No. 53 located in the IPDM E/R. Refer to PG-3
.
• Harness for short or open between battery and transfer control unit harness connector terminals
47.
• Harness for short or open between battery and transfer control unit harness connector terminal
29.
• Harness for short or open between battery and transfer shut off relay harness connector E69
terminal 1, and 3.
• Harness for short or open between transfer shut off relay harness connector E69 terminal 2 and
transfer control unit harness connector terminal 30.
• Harness for short or open between transfer shut off relay harness connector E69 terminal 5 and
transfer control unit harness connector terminals 16 and 22.
• Battery and ignition switch. Refer to PG-3
.
• Transfer shut off relay. Refer to "COMPONENT INSPECTION" .
2.CHECK GROUND CIRCUIT
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.
3. Check continuity between transfer control unit harness connec-
tor E142 terminals 3, 6, E143 terminal 45 and ground.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to ground or short to power
in harness or connectors.
3.CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-35, "
Transfer Control Unit Input/Output Signal Ref-
erence Value".
OK or NG
OK >> GO TO 4.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.
4.CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit. Refer to TF-115, "
Removal and Installation".
Connector Terminal Voltage (Approx.)
E14216 - Ground
Battery voltage 22 - Ground
E14329 - Ground
30 - Ground 0V
47 - Ground Battery voltage
WDIA0166E
Continuity should exist.
SDIA2691E

TROUBLE DIAGNOSIS FOR SYSTEM
TF-53
< SERVICE INFORMATION >
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COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove transfer shut off relay. Refer to TF-22, "
Location of Electrical Parts" .
3. Apply 12V direct current between transfer shut off relay termi-
nals 1 and 2.
4. Check continuity between relay terminals 3 and 5.
5. If NG, replace the transfer shut off relay. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
Transfer Control UnitINFOID:0000000003532530
DIAGNOSTIC PROCEDURE
1.INSPECTION START
Do you have CONSULT-II?
YES or NO
YES >> GO TO 2.
NO >> GO TO 3.
2.PERFORM SELF-DIAGNOSIS (WITH CONSULT-II)
With CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “SELF-DIAG RESULTS” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Touch “ERASE”.
4. Turn ignition switch “OFF” and wait at least 10 seconds.
5. Perform the self-diagnosis again.
Is the
“CONTROL UNIT 1 [P1802]”, “CONTROL UNIT 2 [P1803]”, “CONTROL UNIT 3 [P1804]” or “CONTROL
UNIT 4 [P1809]” displayed?
YES >> Replace transfer control unit. Refer to TF-115, "Removal and Installation" .
NO >> Inspection End.
3.PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-II)
Without CONSULT-II
1. Perform the self-diagnosis and then erase self-diagnostic results. Refer to TF-48, "Self-Diagnosis Proce-
dure" and TF-48, "Self-Diagnosis Procedure" .
2. Perform the self-diagnosis again.
Do the self-diagnostic results indicate AD converter?
YES >> Replace transfer control unit. Refer to TF-115, "Removal and Installation" .
NO >> Inspection End.
Output Shaft Revolution Signal (TCM)INFOID:0000000003532531
DIAGNOSTIC PROCEDURE
1.CHECK DTC WITH TCM
Perform self-diagnosis with TCM. Refer to TF-48, "
Self-Diagnosis Procedure" ..
Is any malfunction detected by self-diagnosis?
YES >> Check the malfunctioning system.
NO >> GO TO 2.
Condition Continuity
12V direct current supply between terminals 1 and 2 Yes
OFF No
SCIA1245E

TROUBLE DIAGNOSIS FOR SYSTEM
TF-55
< SERVICE INFORMATION >
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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.
DIAGNOSTIC PROCEDURE
1.CHECK 4LO POSITION SWITCH SIGNAL
With CONSULT-II
1. Start engine.
2. Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-II.
3. Read out the value of “N POSI SW TF”.
Without CONSULT-II
1. Start engine.
2. Check voltage between transfer control unit harness connector
terminal and ground.
OK or NG
OK >> GO TO 5.
NG >> GO TO 2.
2.CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND NEUTRAL-4LO SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and the neutral-4LO switch harness connector.
Te r m i n a lWire
colorItem Condition Data (Approx.)
25 V Neutral-4LO switch• Vehicle stopped
• Engine running
• A/T selector le-
ver “N” position
• Brake pedal de-
pressed4WD shift switch: 2WD, AUTO or 4H Battery voltage
4WD shift switch: 4H to 4LO (While actua-
tor motor is operating.)Battery voltage
→ 0V
4WD shift switch: 4LO to 4H (While actua-
tor motor is operating.)0V → Battery
voltage
4WD shift switch: 4LO 0V
Condition Display value
• Vehicle stopped
• Engine running
• A/T selector lever “N” position
• Brake pedal depressed4WD shift switch: 2WD,
AUTO or 4HOFF
4WD shift switch: 4H to
4LO (While actuator mo-
tor is operating.)OFF → ON
4WD shift switch: 4LO to
4H (While actuator motor
is operating.)ON → OFF
4WD shift switch: 4LO ON
SDIA2692E
ConnectorTe r m i n a l
(Wire col-
or)ConditionVoltage
(Approx.)
E143 25 -
Ground• Vehicle stopped
• Engine running
• A/T selector lever
“N” position
• Brake pedal de-
pressed4WD shift switch:
2WD, AUTO or 4HBattery
voltage
4WD shift switch: 4H to
4LO (While actuator
motor is operating.)Battery
voltage
→ 0V
4WD shift switch: 4LO
to 4H (While actuator
motor is operating.)0V →
Battery
voltage
4WD shift switch: 4LO 0V
SDIA2693E