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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 .
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CAN COMMUNICATIONEC-31
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CAN COMMUNICATIONPFP:23710
System DescriptionUBS00KZE
CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle mul-
tiplex communication line with high data communication speed and excellent error detection ability. Many elec-
tronic control units are equipped onto a vehicle, and each control unit shares information and links with other
control units during operation (not independent). In CAN communication, control units are connected with 2
communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring.
Each control unit transmits/receives data but selectively reads required data only.
Refer to LAN-26, "
CAN COMMUNICATION" , about CAN communication for detail.
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EC-32Revision: November 2009
EVAPORATIVE EMISSION SYSTEM
2006 QX56
EVAPORATIVE EMISSION SYSTEMPFP:14950
DescriptionUBS00KZF
SYSTEM DESCRIPTION
The evaporative emission system is used to reduce hydrocarbons emitted into the atmosphere from the fuel
system. This reduction of hydrocarbons is accomplished by activated charcoals in the EVAP canister.
The fuel vapor in the sealed fuel tank is led into the EVAP canister which contains activated carbon and the
vapor is stored there when the engine is not operating or when refueling to the fuel tank.
The vapor in the EVAP canister is purged by the air through the purge line to the intake manifold when the
engine is operating. EVAP canister purge volume control solenoid valve is controlled by ECM. When the
engine operates, the flow rate of vapor controlled by EVAP canister purge volume control solenoid valve is
proportionally regulated as the air flow increases.
EVAP canister purge volume control solenoid valve also shuts off the vapor purge line during decelerating and
idling.
PBIB1631E
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EVAPORATIVE EMISSION SYSTEMEC-33
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Revision: November 2009 2006 QX56
EVAPORATIVE EMISSION LINE DRAWING
PBIB2053E
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EC-34Revision: November 2009
EVAPORATIVE EMISSION SYSTEM
2006 QX56
BBIA0444E
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EVAPORATIVE EMISSION SYSTEMEC-35
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Component InspectionUBS00KZG
EVAP CANISTER
Check EVAP canister as follows:
1. Block port B .
2. Blow air into port A and check that it flows freely out of port C .
3. Release blocked port B .
4. Apply vacuum pressure to port B and check that vacuum pres-
sure exists at the ports A and C .
5. Block port A and B .
6. Apply pressure to port C and check that there is no leakage.
FUEL TANK VACUUM RELIEF VALVE (BUILT INTO FUEL FULLER CAP)
1. Wipe clean valve housing.
2. Check valve opening pressure and vacuum.
3. If out of specification, replace fuel filler cap as an assembly.
CAUTION:
Use only a genuine fuel filler cap as a replacement. If an incor-
rect fuel filler cap is used, the MIL may come on.
EVAP CANISTER PURGE VOLUME CONTROL SOLENOID VALVE
Refer to EC-373 and EC-381 .
FUEL TANK TEMPERATURE SENSOR
Refer to EC-309 and EC-315 .
EVAP CANISTER VENT CONTROL VALVE
Refer to EC-388 and EC-395 .
EVAP CONTROL SYSTEM PRESSURE SENSOR
Refer to EC-402 , EC-405 and EC-411 .
PBIB1212E
SEF445Y
Pressure:
15.3 - 20.0 kPa (0.156 - 0.204 kg/cm2 , 2.22
- 2.90 psi)
Va c u u m : −6.0 to −3.3 kPa ( −0.061 to − 0.034 kg/cm
2 ,
− 0.87 to −0.48 psi)
SEF943S
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EC-36Revision: November 2009
EVAPORATIVE EMISSION SYSTEM
2006 QX56
EVAP SERVICE PORT
Positive pressure is delivered to the EVAP system through the EVAP
service port. If fuel vapor leakage in the EVAP system occurs, use a
leak detector to locate the leak.
Removal and InstallationUBS00KZH
EVAP CANISTER
Tighten EVAP canister as shown in the figure.
EVAP CANISTER VENT CONTROL VALVE
1. Turn EVAP canister vent control valve counterclockwise.
2. Remove the EVAP canister vent control valve.
Always replace O-ring with a new one.
BBIA0366E
: N-·m (kg-m, in-lb)
BBIA0349E
BBIA0350E
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EVAPORATIVE EMISSION SYSTEMEC-37
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How to Detect Fuel Vapor LeakageUBS00KZI
CAUTION:
Never use compressed air or a high pressure pump.
Do not exceed 4.12 kPa (0.042 kg/cm2 , 0.6 psi) of pressure in EVAP system.
NOTE:
Do not start engine.
Improper installation of EVAP service port adapter to the EVAP service port may cause a leak.
WITH CONSULT-II
1. Attach the EVAP service port adapter securely to the EVAP service port.
2. Also attach the pressure pump and hose to the EVAP service port adapter.
3. Turn ignition switch ON.
4. Select the “EVAP SYSTEM CLOSE ” of “WORK SUPPORT
MODE ” with CONSULT-II.
5. Touch “START”. A bar graph (Pressure indicating display) will
appear on the screen.
6. Apply positive pressure to the EVAP system until the pressure indicator reaches the middle of the bar graph.
7. Remove EVAP service port adapter and hose with pressure pump.
8. Locate the leak using a leak detector. Refer to EC-33, "
EVAPO-
RATIVE EMISSION LINE DRAWING" .
PEF838U
PEF917U
SEF200U