EC-30Revision: November 2009
AUTOMATIC SPEED CONTROL DEVICE (ASCD)
2006 QX56
COAST OPERATION
When the SET/COAST switch is pressed during cruise control driving, decrease vehicle set speed until the
switch is released. And then ASCD will keep the new set speed.
RESUME OPERATION
When the RESUME/ACCELERATE switch is pressed after cancel operation other than pressing MAIN switch
is performed, vehicle speed will return to last set speed. To resume vehicle set speed, vehicle condition must
meet following conditions.
Brake pedal is released
A/T selector lever is in other than P and N positions
Vehicle speed is greater than 40 km/h (25 MPH) and less than 144 km/h (89 MPH)
Component DescriptionUBS00KZD
ASCD STEERING SWITCH
Refer to EC-494 .
ASCD BRAKE SWITCH
Refer to EC-511 , and EC-586 .
STOP LAMP SWITCH
Refer to EC-511 , EC-523 and EC-586 .
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EC-528 , EC-534 , EC-540 and EC-545 .
ASCD INDICATOR
Refer to EC-593 .
ASCD INDICATOREC-593
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Revision: November 2009 2006 QX56
ASCD INDICATORPFP:24814
Component DescriptionUBS00HDT
ASCD indicator lamp illuminates to indicate ASCD operation status. Lamp has two indicators, CRUISE and
SET, and is integrated in combination meter.
CRUISE indicator illuminates when MAIN switch on ASCD steering switch is turned ON to indicate that ASCD
system is ready for operation.
SET indicator illuminates when following conditions are met.
CRUISE indicator is illuminated.
SET/COAST switch on ASCD steering switch is turned ON while vehicle speed is within the range of
ASCD setting.
SET indicator remains lit during ASCD control.
Refer to EC-29, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)" for the ASCD function.
CONSULT-II Reference Value in Data Monitor ModeUBS00HDU
Specification data are reference value.
MONITOR ITEM CONDITIONSPECIFICATION
CRUISE LAMP
Ignition switch: ONMAIN switch: Pressed at the 1st
time → at the 2nd time ON
→ OFF
SET LAMP
MAIN switch: ON
When vehicle speed is
between 40 km/h (25 MPH)
and 144 km/h (89 MPH)
ASCD: Operating ON
ASCD: Not operatingOFF
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ALPHABETICAL INDEX
H
H/AIM - Wiring diagram ...................................... LT-66
H/LAMP - Wiring diagram .................................... LT-9
Handling precautions for plastics ..................... BL-187
Harness connector ............................................ PG-68
Harness layout .................................................. PG-41
Hazard warning lamp ......................................... LT-80
Headlamp ............................................................. LT-5
Headlamp aiming control ................................... LT-66
Headlamp leveler - See Headlamp aiming control . LT-
66
Headlamp removal and installation .................... LT-31
Heated oxygen sensor 2 (bank 1) .... EC-253, EC-264,
EC-277
Heated oxygen sensor 2 (bank 2) .... EC-253, EC-264,
EC-277
Heated oxygen sensor 2 heater (bank 1) ........ EC-163
Heated oxygen sensor 2 heater (bank 2) ........ EC-163
Heated seat ....................................................... SE-84
Heater and cooling unit (Heater core) . ATC-153, ATC-
156
Heater unit (heater core) ............... ATC-153, ATC-156
Height (Dimensions) ........................................... GI-50
HFC134a (R134a) system identification ........... ATC-6
HFC134a (R134a) system precaution ............... ATC-5
HFC134a (R134a) system service procedure ATC-171
HFC134a (R134a) system service tools ......... ATC-14
HFC134a system service equipment precaution ATC-
11
High and low reverse clutch solenoid valve .... AT-151,
AT-153
Homelink universal transceiver ........................ BL-156
Horn ................................................................ WW-55
HORN - Wiring diagram .................................. WW-55
How to erase DTC for OBD system .................. EC-61
HSEAT - Wiring diagram ................................... SE-86
I
IATS - Wiring diagram ..................................... EC-189
ICC - Wiring diagram ....................................... ACS-20
ICC/BS - Wiring diagram ................................. EC-504
ICC/SW - Wiring diagram ................................ EC-489
ICCBOF - Wiring diagram ............................... EC-611
Identification plate .............................................. GI-48
Idle air volume learning ..................................... EC-78
Idle speed .............................................. EC-71, EC-76
Idle speed control (ISC) .................... EC-444, EC-446
Ignition coil .......................................... EM-28, EC-618
Ignition control system .................................... EC-618
Ignition key hole illumination ............................ LT-134
Ignition timing ........................................ EC-71, EC-76
IGNSYS - Wiring diagram ............................... EC-619
ILL - Wiring diagram ......................................... LT-163
Illumination ....................................................... LT-157
In vehicle sensor ........................... ATC-137, ATC-146
In-cabin Microfilter ............................................. MA-21
INJECT - Wiring diagram ................................ EC-599
Injector ............................................................. EC-598
Input clutch solenoid valve ................. AT-139, AT-141
Instrument panel .................................................. IP-10
Intake air temperature sensor ............ EC-188, EC-208
Intake door control linkage adjustment . ATC-85, ATC-
88
Intake door motor ........................... ATC-83, ATC-160
Intake manifold .................................................. EM-17
Intake sensor ................................ ATC-142, ATC-148
Integrated homelink transmitter - See Homelink univer-
sal tranceiver .................................................... BL-156
Intelligent cruise control (ICC) system ............... ACS-6
Interior ................................................................. EI-35
Interior lamp ...................................................... LT-134
Interior lamp on-off control ................................ LT-135
Internal gear (Transfer) ....................... TF-149, TF-176
IPDM (Intelligent power distribution module engine
room) ................................................................. PG-18
IVIS (Infiniti vehicle immobilizer system) .......... BL-137
IVIS (Infiniti vehicle immobilizer system) precautions ...
GI-3
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Jacking points ..................................................... GI-41
Junction box (J/B) .............................................. PG-76
K
Key illumination ................................................ LT-135
KEYLES - Wiring diagram .................................. BL-49
Knock sensor (KS) ........................................... EC-335
KS - Wiring diagram ........................................ EC-336
L
Laser beam aiming adjustment ....................... ACS-12
Length (Dimensions) .......................................... GI-50
License lamp .................................................... LT-111
Lifting points ....................................................... GI-42
Line pressure solenoid valve ........................... AT-122
Line pressure switch (Transfer) .......... TF-154, TF-167
Line pressure test (A/T) ..................................... AT-52
Location of electrical units ................................. PG-65
Low coast brake solenoid valve .......... AT-155, AT-157
Low tire pressure warning system ...................... WT-8
Low tire pressure warning system - trouble diagnoses
WT-11
Low tire pressure warning system - Wiring diagram .....
WT-11
Lubricant (R134a) A/C ..................................... ATC-22
Lubricants .......................................................... MA-11
Lubrication circuit (engine) .................................. LU-5
Lubrication oil A/C ........................................... ATC-22
Lubrication-locks, hinges and hood latches ....... MA-31
M
MAFS - Wiring diagram ..................... EC-174
, EC-182
LAN-32
[CAN]
CAN COMMUNICATION
Revision: November 20092006 QX56
Ty p e 2
Input/output signal chart
T: Transmit R: Receive
PKIC3015E
SignalsECM
TCM
ICC sensor
*1
ICC unit
*1
Driver seat control unit Combination meter
Display control unit BCM
Steering angle sensor Front air control
ABS actuator and electric unit (control unit) IPDM E/R
A/C compressor request signal T R
Accelerator pedal position signal T RR R
ASCD CRUISE lamp signal TR
ASCD OD cancel request signal T R
ASCD operation signal T R
ASCD SET lamp signal TR
Battery voltage signal T R
Closed throttle position signal T R R
Cooling fan speed request signal T R
Engine coolant temperature signal TRR
Engine speed signal T RRR R R R
Engine status signal TR
Fuel consumption monitor signal TR
TR
ICC steering switch signal TR
Malfunction indicator lamp signal TR
Wide open throttle position signal T R
A/T CHECK indicator lamp signal TR
LAN-36
[CAN]
CAN COMMUNICATION
Revision: November 20092006 QX56
ASCD CRUISE lamp signalTR
ASCD OD cancel request signal T R
ASCD operation signal T R
ASCD SET lamp signal TR
Battery voltage signal T R
Closed throttle position signal T R R
Cooling fan speed request signal T R
Engine coolant temperature signal TRR
Engine speed signal T RRR R R R R
Engine status signal TR
Fuel consumption monitor signal TR
TR
ICC steering switch signal TR
Malfunction indicator lamp signal TR
Wide open throttle position signal T R
A/T CHECK indicator lamp signal TR
A/T fluid temperature sensor signal TR
A/T position indicator lamp signal TR R R
A/T self-diagnosis signal R T
Current gear position signal TR R
Output shaft revolution signal R TR R
P range signal TR R R
Turbine revolution signal R TR
ICC sensor signal T R
Buzzer output signal TR
RT
ICC OD cancel request signal R RT
ICC operation signal R RT
ICC system display signal TR
System setting signal TR
RT
1st position switch signal RT
4th position switch signal RT
Distance to empty signal T R
Signals
ECM
TCM
ICC sensor
*1
ICC unit
*1
Driver seat control unit Combination meter
Display control unit BCM
Steering angle sensor Front air control
Transfer control unit
ABS actuator and electric unit (control unit) IPDM E/R
HARNESSPG-63
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Revision: November 2009 2006 QX56
HORNWW Horn
HSEAT SE Heated Seat
ICC ACS Intelligent Cruise Control
ICCBOF EC ICC Brake Switch
ICC/BS EC ICC Steering Switch
ICC/SW EC ICC Brake Switch
I/MIRR GW Inside Mirror (Auto Anti-Dazzling Mirror)
IATS EC Intake Air Temperature Sensor
IGNSYS EC Ignition System
ILL LT Illumination
INJECT EC Injector
INT/L LT Room/Map, Vanity, Cargo, Personal, Foot, Step, and Puddle Lamps
KEYLES BL Remote Keyless Entry System
KS EC Knock Sensor
MAFS EC Mass Air Flow Sensor
MAIN EC Main Power Supply and Ground Circuit
METER DI Speedometer, Tachometer, Temp. and Fuel Gauges
MIL/DL EC Malfunction Indicator Lamp
MIRROR GW Door Mirror
NATS BL Nissan Anti-Theft System
NAVI AV Navigation System
O2H2B1 EC Rear Heated Oxygen Sensor 2 Heater Bank 1
O2H2B2 EC Rear Heated Oxygen Sensor 2 Heater Bank 2
O2S2B1 EC Heated Oxygen Sensor 2 Bank 1
O2S2B2 EC Heated Oxygen Sensor 2 Bank 2
P/SCKT WW Power Socket
PGC/V EC EVAP Canister Purge Volume Control Solenoid Valve
PHASE EC Camshaft Position Sensor (PHASE) (Bank 1)
PNP/SW EC Park/Neutral Position Switch
POS EC Crankshaft Position Sensor (POS)
POWER PG Power Supply Routing
PRE/SE EC EVAP Control System Pressure Sensor
PS/SEN EC Power Steering Pressure Sensor
R/VIEW DI Rear View Monitor
RP/SEN EC Refrigerant Pressure Sensor
SEN/PW EC Sensor Power Supply
SHIFT AT A/T Shift Lock System
SONAR DI Rear Sonar System
SROOF RF Sunroof
SRS SRS Supplemental Restraint System
START SC Starting System
STOP/L LT Stop Lamp
T/TOW LT Trailer Tow
T/WARN WT Low Tire Pressure Warning System
TAIL/L LT Parking, License and Tail Lamps
T/F TFTransfer Case
TPS1 EC Throttle Position Sensor
TPS2 EC Throttle Position Sensor
TPS3 EC Throttle Position Sensor
TRNSCV BL HOMELINK® Universal Transceiver
TURN LT Turn Signal and Hazard Warning Lamps
VDC BRC Vehicle Dynamic Control System
TF-1
TRANSFER
D DRIVELINE/AXLE
CONTENTS
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Revision: November 2009 2006 QX56
PRECAUTIONS .....................................................
..... 4
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” ............................................................. ..... 4
Precautions for Transfer Assembly and Transfer
Control Unit Replacement ................................... ..... 4
METHOD FOR POSITION ADJUSTMENT ...... ..... 4
Precautions ......................................................... ..... 4
Service Notice .......................................................... 5
PREPARATION ...................................................... ..... 6
Special Service Tools .......................................... ..... 6
Commercial Service Tools ................................... ..... 9
NOISE, VIBRATION AND HARSHNESS (NVH)
TROUBLESHOOTING ........................................... ... 10
NVH Troubleshooting Chart ................................ ... 10
TRANSFER FLUID ................................................ ....11
Replacement ....................................................... .... 11
DRAINING ........................................................ .... 11
FILLING ............................................................ .... 11
Inspection ............................................................ .... 11
FLUID LEAKAGE AND FLUID LEVEL ............. .... 11
ALL-MODE 4WD SYSTEM ................................... ... 12
Cross-section View ............................................. ... 12
Power Transfer .................................................... ... 13
POWER TRANSFER DIAGRAM ..................... ... 13
POWER TRANSFER FLOW ............................ ... 14
System Description ............................................. ... 15
CONTROL SYSTEM ........................................ ... 15
TRANSFER MOTOR ....................................... ... 16
WAIT DETECTION SWITCH ........................... ... 17
NEUTRAL-4LO SWITCH ................................. ... 17
ATP SWITCH ................................................... ... 17
2-4WD SHIFT SOLENOID VALVE ................... ... 17
CLUTCH PRESSURE SOLENOID VALVE ...... ... 18
LINE PRESSURE SWITCH ............................. ... 18
CLUTCH PRESSURE SWITCH ....................... ... 18
TRANSFER FLUID TEMPERATURE SENSOR ... 18
TRANSFER CONTROL UNIT .......................... ... 18
TRANSFER CONTROL DEVICE ..................... ... 18
4WD SHIFT SWITCH AND INDICATOR LAMP ... 184WD WARNING LAMP ....................................
... 19
ATP WARNING LAMP ...................................... ... 19
System Diagram ..................................................... 19 COMPONENTS FUNCTION ............................ ... 20
CAN Communication .............................................. 20 SYSTEM DESCRIPTION ................................. ... 20
TROUBLE DIAGNOSIS ......................................... ... 21
How to Perform Trouble Diagnosis ...................... ... 21
BASIC CONCEPT ............................................ ... 21
Location of Electrical Parts .................................. ... 22
Circuit Diagram ....................................................... 23
Wiring Diagram — T/F — .................................... ... 24
Inspections Before Trouble Diagnosis ................. ... 32
TRANSFER FLUID CHECK ............................. ... 32
PREPARATION FOR ROAD TEST .................. ... 32
CHECK BEFORE ENGINE IS STARTED ........ ... 32
CHECK AT IDLE ............................................... ... 32
CRUISE TEST ..................................................... 33
Trouble Diagnosis Chart for Symptoms ............... ... 34
Transfer Control Unit Input/Output Signal Refer-
ence Values ......................................................... ... 35
TRANSFER CONTROL UNIT INSPECTION
TABLE .............................................................. ... 35
CONSULT-II Function (ALL MODE AWD/4WD) .. ... 44
FUNCTION ....................................................... ... 44
CONSULT-II SETTING PROCEDURE ............. ... 44
SELF-DIAG RESULT MODE ............................ ... 45
DATA MONITOR MODE ................................... ... 47
WORK SUPPORT ............................................ ... 49
Self-diagnostic Procedure ................................... ... 50
SELF-DIAGNOSTIC PROCEDURE (WITH
CONSULT-II) .................................................... ... 50
SELF-DIAGNOSTIC PROCEDURE (WITHOUT
CONSULT-II) .................................................... ... 50
ERASE SELF-DIAGNOSIS .............................. ... 53
TROUBLE DIAGNOSIS FOR SYSTEM ................. ... 54
Power Supply Circuit For Transfer Control Unit ... ... 54
CONSULT-II REFERENCE VALUE IN DATA
MONITOR MODE ............................................. ... 54
TRANSFER CONTROL UNIT TERMINALS AND
TROUBLE DIAGNOSIS FOR SYSTEMTF-107
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Revision: November 2009 2006 QX56
3. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-54, "
TRANSFER CONTROL UNIT TERMINALS
AND REFERENCE VALUE" .
OK or NG
OK >> GO TO 4.
NG >> Check transfer control unit pin terminals for damage or loose connection with the harness connec- tor. If any items are damaged, repair or replace damaged parts.
4. CHECK CLUTCH PRESSURE SWITCH
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove clutch pressure switch. Refer to TF-22, "
Location of Electrical Parts" .
3. Push and release clutch pressure switch and check continuity between transfer terminal cord assembly terminal 7 and ground.
OK or NG
OK >> GO TO 5.
NG >> Replace clutch pressure switch. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
5. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> GO TO 6.
NG >> Replace transfer control unit. Refer to TF-132, "
Removal and Installation" .
6. CRUISE TEST
Perform cruise test. Refer to TF-33, "
CRUISE TEST" .
OK or NG
OK >> Inspection End.
NG >> Perform the applicable trouble diagnosis.
COMPONENT INSPECTION
1. Turn ignition switch “OFF”. (Stay for at least 5 seconds.)
2. Remove clutch pressure switch. Refer to TF-22, "
Location of Electrical Parts" .
3. Push and release clutch pressure switch and check continuity between transfer terminal cord assembly terminal 7 and ground.
4. If NG, replace the clutch pressure switch. Refer to TF-22, "
Loca-
tion of Electrical Parts" .
TerminalCondition Continuity
7 -
Ground Push clutch pressure switch
Yes
Release clutch pressure switch No
WDIA0171E
TerminalCondition Continuity
7 - Ground Push clutch pressure switch
Yes
Release clutch pressure switch No
WDIA0171E