Page 1697 of 3383
EC-486Revision: November 2009
DTC P1226 TP SENSOR
2006 QX56
Diagnostic ProcedureUBS00H99
1. CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY
1. Turn ignition switch OFF.
2. Remove the intake air duct.
3. Check if foreign matter is caught between the throttle valve and the housing.
OK or NG
OK >> GO TO 2.
NG >> Remove the foreign matter and clean the electric throttle control actuator inside.
2. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR
1. Replace the electric throttle control actuator.
2. Perform EC-78, "
Throttle Valve Closed Position Learning" .
3. Perform EC-78, "
Idle Air Volume Learning" .
>> INSPECTION END
Removal and InstallationUBS00H9A
ELECTRIC THROTTLE CONTROL ACTUATOR
Refer to EM-17, "INTAKE MANIFOLD" .
BBIA0364E
Page 1701 of 3383

EC-490Revision: November 2009
DTC P1564 ICC STEERING SWITCH
2006 QX56
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00L1R
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
67 B Sensor ground [Engine is running]
Warm-up condition
Idle speed
Approximately 0V
99 G/Y ICC steering switch [Ignition switch: ON]
ICC steering switch: OFF
Approximately 4.3V
[Ignition switch: ON]
MAIN switch: Pressed Approximately 0V
[Ignition switch: ON]
CANCEL switch: Pressed Approximately 1.3V
[Ignition switch: ON]
RESUME/ACCELERATE switch: Pressed Approximately 3.7V
[Ignition switch: ON]
SET/COAST switch: Pressed Approximately 3V
[Ignition switch: ON]
DISTANCE switch: Pressed Approximately 2.2V
BBIA0354E
Page 1708 of 3383

DTC P1564 ASCD STEERING SWITCHEC-497
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EC
Revision: November 2009 2006 QX56
Specification data are reference values and are measured between each terminal and ground.
CAUTION:
Do not use ECM ground terminals when measuring input/output voltage. Doing so may result in dam-
age to the ECM's transistor. Use a ground other than ECM terminals, such as the ground.
Diagnostic ProcedureUBS00L11
1. CHECK GROUND CONNECTIONS
1. Turn ignition switch OFF.
2. Loosen and retighten three ground screws on the body. Refer to EC-150, "
Ground Inspection" .
OK or NG
OK >> GO TO 2.
NG >> Repair or replace ground connections.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
67 B Sensor ground [Engine is running]
Warm-up condition
Idle speed
Approximately 0V
99 G/Y ASCD steering switch [Ignition switch: ON]
ASCD steering switch: OFF
Approximately 4V
[Ignition switch: ON]
MAIN switch: ON Approximately 0V
[Ignition switch: ON]
CANCEL switch: ON Approximately 1V
[Ignition switch: ON]
RESUME/ACCELERATTTE switch: ON Approximately 3V
[Ignition switch: ON]
SET/COAST switch: ON Approximately 2V
BBIA0354E
Page 1730 of 3383

DTC P1574 ICC VEHICLE SPEED SENSOREC-519
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Revision: November 2009 2006 QX56
DTC P1574 ICC VEHICLE SPEED SENSORPFP:31036
Component DescriptionUBS00HZ6
The ECM receives two vehicle speed signals via CAN communication line. One is sent from “unified meter and
A/C amp. ”, and the other is from TCM (Transmission control module). The ECM uses these signals for ICC
control. Refer to ACS-6, "
DESCRIPTION" for ICC functions.
On Board Diagnosis LogicUBS00HZ7
This self-diagnosis has the one trip detection logic.
The MIL will not light up for this self-diagnosis.
NOTE:
If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-151, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
If DTC P1574 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010.
Refer to EC-154, "
DTC U1010 CAN COMMUNICATION" .
If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500.
Refer to EC-442, "
DTC P0500 VSS" .
If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-457, "
DTC P0605 ECM" .
DTC Confirmation ProcedureUBS00HZ8
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Step 3 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-II
1. Start engine.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Drive the vehicle at more than 40 km/h (25MPH).
4. If DTC is detected, go to EC-520, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble Diagnosis Name DTC Detecting Condition Possible Cause
P1574
1574 ICC vehicle speed sensor ECM detects a difference between two vehicle
speed signals is out of the specified range.
Harness or connectors
(The CAN communication line is open or
shorted.)
Combination meter
ABS actuator and electric unit (control unit)
Wheel sensor
TCM
ECM
SEF058Y
Page 1731 of 3383
EC-520Revision: November 2009
DTC P1574 ICC VEHICLE SPEED SENSOR
2006 QX56
Diagnostic ProcedureUBS00HZ9
1. CHECK DTC WITH TCM
Check DTC with TCM. Refer to AT- 3 8 , "
OBD-II Diagnostic Trouble Code (DTC)" .
OK or NG
OK >> GO TO 2.
NG >> Perform trouble shooting relevant to DTC indicated.
2. CHECK DTC WITH “ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)”
Refer to BRC-11, "
TROUBLE DIAGNOSIS" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3. CHECK COMBINATION METER FUNCTION
Refer to DI-5, "
COMBINATION METERS" .
>> INSPECTION END
Page 1732 of 3383

DTC P1574 ASCD VEHICLE SPEED SENSOREC-521
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Revision: November 2009 2006 QX56
DTC P1574 ASCD VEHICLE SPEED SENSORPFP:31036
Component DescriptionUBS00HBM
The ECM receives two vehicle speed sensor signals via CAN communication line. One is sent from combina-
tion meter and the other is from TCM (Transmission control module). The ECM uses these signals for ASCD
control. Refer to EC-29, "
AUTOMATIC SPEED CONTROL DEVICE (ASCD)" for ASCD functions.
On Board Diagnosis LogicUBS00HBN
This self-diagnosis has the one trip detection logic.
The MIL will not light up for this diagnosis.
NOTE:
If DTC P1574 is displayed with DTC U1000, U1001, first perform the trouble diagnosis for DTC
U1000, U1001. Refer to EC-151, "
DTC U1000, U1001 CAN COMMUNICATION LINE" .
If DTC P1574 is displayed with DTC U1010, first perform the trouble diagnosis for DTC U1010.
Refer to EC-154, "
DTC U1010 CAN COMMUNICATION" .
If DTC P1574 is displayed with DTC P0500, first perform the trouble diagnosis for DTC P0500.
Refer to EC-442, "
DTC P0500 VSS".
If DTC P1574 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-457, "
DTC P0605 ECM".
DTC Confirmation ProcedureUBS00HBO
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Step 3 may be conducted with the drive wheels lifted in the shop or by driving the vehicle. If a road test
is expected to be easier, it is unnecessary to lift the vehicle.
WITH CONSULT-II
1. Start engine (VDC switch OFF).
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Drive the vehicle at more than 40 km/h (25 MPH).
4. If DTC is detected, go to EC-522, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No.Trouble Diagnosis
Name DTC Detecting Condition
Possible Cause
P1574
1574 ASCD vehicle speed
sensor ECM detects a difference between two vehicle
speed signals is out of the specified range.
Harness or connectors
(The CAN communication line is open or
shorted.)
Combination meter
ABS actuator and electric unit (control unit)
Wheel sensor
TCM
ECM
SEF058Y
Page 1733 of 3383
EC-522Revision: November 2009
DTC P1574 ASCD VEHICLE SPEED SENSOR
2006 QX56
Diagnostic ProcedureUBS00HBP
1. CHECK DTC WITH TCM
Check DTC with TCM. Refer to AT- 3 8 , "
OBD-II Diagnostic Trouble Code (DTC)" .
OK or NG
OK >> GO TO 2.
NG >> Perform trouble shooting relevant to DTC indicated.
2. CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)
Refer to BRC-11, "
TROUBLE DIAGNOSIS" .
OK or NG
OK >> GO TO 3.
NG >> Repair or replace.
3. CHECK COMBINATION METER FUNCTION
Check combination meter function.
Refer to DI-5, "
COMBINATION METERS" .
>> INSPECTION END
Page 1745 of 3383

EC-534Revision: November 2009
DTC P2101 ELECTRIC THROTTLE CONTROL FUNCTION
2006 QX56
DTC P2101 ELECTRIC THROTTLE CONTROL FUNCTIONPFP:16119
DescriptionUBS00H7I
NOTE:
If DTC P2101 is displayed with DTC P2100 or 2119, first perform the trouble diagnosis for DTC P2100
or P2119. Refer to EC-528, "
DTC P2100, P2103 THROTTLE CONTROL MOTOR RELAY" or EC-545,
"DTC P2119 ELECTRIC THROTTLE CONTROL ACTUATOR" .
Electric throttle control actuator consists of throttle control motor, throttle position sensor, etc.
The throttle control motor is operated by the ECM and it opens and closes the throttle valve.
The current opening angle of the throttle valve is detected by the throttle position sensor and it provides feed-
back to the ECM to control the throttle control motor to make the throttle valve opening angle properly in
response to driving condition.
On Board Diagnosis LogicUBS00H7J
This self-diagnosis has the one trip detection logic.
FAIL-SAFE MODE
When the malfunction is detected, ECM enters fail-safe mode and the MIL lights up.
DTC Confirmation ProcedureUBS00H7K
NOTE:
If DTC Confirmation Procedure has been previously conducted, always turn ignition switch OFF and wait at
least 10 seconds before conducting the next test.
TESTING CONDITION:
Before performing the following procedure, confirm that battery voltage is more than 11V when engine
is running.
WITH CONSULT-II
1. Turn ignition switch ON and wait at least 2 seconds.
2. Select “DATA MONITOR ” mode with CONSULT-II.
3. Start engine and let it idle for 5 seconds.
4. If DTC is detected, go to EC-536, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
DTC No. Trouble diagnosis name DTC detecting condition Possible cause
P2101
2101 Electric throttle control
performance Electric throttle control function does not oper-
ate properly.
Harness or connectors
(Throttle control motor circuit is open or
shorted)
Electric throttle control actuator
Engine operating condition in fail-safe mode
ECM stops the electric throttle control actuator control, throttle valve is maintained at a fixed opening (approx. 5 degrees) by the return
spring.
SEF058Y