EC-78Revision: November 2009
BASIC SERVICE PROCEDURE
2006 QX56
Accelerator Pedal Released Position LearningUBS00KZY
DESCRIPTION
Accelerator Pedal Released Position Learning is an operation to learn the fully released position of the accel-
erator pedal by monitoring the accelerator pedal position sensor output signal. It must be performed each time
harness connector of accelerator pedal position sensor or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON and wait at least 2 seconds.
3. Turn ignition switch OFF and wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF and wait at least 10 seconds.
Throttle Valve Closed Position LearningUBS00KZZ
DESCRIPTION
Throttle Valve Closed Position Learning is an operation to learn the fully closed position of the throttle valve by
monitoring the throttle position sensor output signal. It must be performed each time harness connector of
electric throttle control actuator or ECM is disconnected.
OPERATION PROCEDURE
1. Make sure that accelerator pedal is fully released.
2. Turn ignition switch ON.
3. Turn ignition switch OFF wait at least 10 seconds.Make sure that throttle valve moves during above 10 seconds by confirming the operating sound.
Idle Air Volume LearningUBS00L00
DESCRIPTION
Idle Air Volume Learning is an operation to learn the idle air volume that keeps each engine within the specific
range. It must be performed under any of the following conditions:
Each time electric throttle control actuator or ECM is replaced.
Idle speed or ignition timing is out of specification.
PREPARATION
Before performing Idle Air Volume Learning, make sure that all of the following conditions are satisfied.
Learning will be cancelled if any of the following conditions are missed for even a moment.
Battery voltage: More than 12.9V (At idle)
Engine coolant temperature: 70 - 100 °C (158 - 212 °F)
Park/Neutral position (PNP) switch: ON
Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine
is start the headlamp will not be illuminated.
Steering wheel: Neutral (Straight-ahead position)
Vehicle speed: Stopped
Transmission: Warmed-up
–With CONSULT-II: Drive vehicle until “ATF TEMP SE 1 ” in “DATA MONITOR” mode of “A/T” system indi-
cates less than 0.9V.
–Without CONSULT-II: Drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-78, "Accelerator Pedal Released Position Learning" .
2. Perform EC-78, "
Throttle Valve Closed Position Learning" .
3. Start engine and warm it up to normal operating temperature.
4. Check that all items listed under the topic PREPARATION (previously mentioned) are in good order.
EC-112Revision: November 2009
TROUBLE DIAGNOSIS
2006 QX56
101 R/W Stop lamp switch[Ignition switch: OFF]Brake pedal: Fully released
Approximately 0V
[Ignition switch: OFF]
Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14V)
102 GR/R PNP switch [Ignition switch: ON]
Selector lever: P or N
Approximately 0V
[Ignition switch: ON]
Except the above gear position BATTERY VOLTAGE
(11 - 14V)
104 O Throttle control motor relay [Ignition switch: OFF]
BATTERY VOLTAGE
(11 - 14V)
[Ignition switch: ON] 0 - 1.0V
106 BR/W Accelerator pedal position
sensor 1 [Ignition switch: ON]
Engine: Stopped
Accelerator pedal: Fully released
0.5 - 1.0V
[Ignition switch: ON]
Engine: Stopped
Accelerator pedal: Fully depressed 4.2 - 4.8V
107 V/R Fuel tank temperature sensor [Engine is running]Approximately 0 - 4.8V
Output voltage varies with fuel
tank temperature.
108 BR/W ICC brake switch
(Models with ICC system)
ASCD brake switch
(Models with ASCD system) [Ignition switch: ON]
Brake pedal: Slightly depressed
Approximately 0V
[Ignition switch: ON]
Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14V)
109 L/W Ignition switch [Ignition switch: OFF]
0V
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
111 W / B ECM relay
(Self shut-off) [Engine is running]
[Ignition switch: OFF]
For a few seconds after turning ignition
switch OFF
0 - 1.5V
[Ignition switch: OFF]
More than a few seconds after turning igni-
tion switch OFF BATTERY VOLTAGE
(11 - 14V)
113 GR Fuel pump relay [Ignition switch: ON]
For 1 second after turning ignition switch
ON
[Engine is running] 0 - 1.5V
[Ignition switch: ON]
More than 1 second after turning ignition
switch ON BATTERY VOLTAGE
(11 - 14V)
11 5
11 6 B
B/W
ECM ground [Engine is running]
Idle speed Body ground
11 7 L / Y EVAP canister vent control
valve
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
11 9
120 BR
BR
Power supply for ECM
[Ignition switch: ON] BATTERY VOLTAGE
(11 - 14V)
121 W Power supply for ECM
(Back-up) [Ignition switch: OFF]
BATTERY VOLTAGE
(11 - 14V)
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
EC-120Revision: November 2009
TROUBLE DIAGNOSIS
2006 QX56
FUEL LEVEL SE
[V]×The signal voltage of the fuel level sen-
sor is displayed.
START SIGNAL
[ON/OFF] ××
Indicates start signal status [ON/OFF]
computed by the ECM according to the
signals of engine speed and battery volt-
age.
After starting the engine, [OFF] is dis-
played regardless of the starter signal.
CLSD THL POS
[ON/OFF] ××
Indicates idle position [ON/OFF] com-
puted by ECM according to the acceler-
ator pedal position sensor signal.
AIR COND SIG
[ON/OFF] ××
Indicates [ON/OFF] condition of the air
conditioner switch as determined by the
air conditioner signal.
P/N POSI SW
[ON/OFF] ××
Indicates [ON/OFF] condition from the
park/neutral position (PNP) switch sig-
nal.
PW/ST SIGNAL
[ON/OFF] ××
[ON/OFF] condition of the power steer-
ing system (determined by the signal
voltage of the power steering pressure
sensor signal) is indicated.
LOAD SIGNAL
[ON/OFF] ××
Indicates [ON/OFF] condition from the
electrical load signal.
ON: Rear window defogger switch is ON
and/or lighting switch is in 2nd position.
OFF: Both rear window defogger switch
and lighting switch are OFF.
IGNITION SW
[ON/OFF] ×
Indicates [ON/OFF] condition from igni-
tion switch signal.
HEATER FAN SW
[ON/OFF] ×
Indicates [ON/OFF] condition from
heater fan switch signal.
BRAKE SW
[ON/OFF] ×
Indicates [ON/OFF] condition from the
stop lamp switch signal.
INJ PULSE-B1
[msec] ×
Indicates the actual fuel injection pulse
width compensated by ECM according
to the input signals.When the engine is stopped, a certain
computed value is indicated.
INJ PULSE-B2
[msec]
IGN TIMING
[BTDC] ×
Indicates the ignition timing computed
by ECM according to the input signals.When the engine is stopped, a certain
value is indicated.
CAL/LD VALUE [%]
“ Calculated load value ” indicates the
value of the current air flow divided by
peak air flow.
MASS AIRFLOW
[g ·m/s]
Indicates the mass air flow computed by
ECM according to the signal voltage of
the mass air flow sensor.
PURG VOL C/V [%]
Indicates the EVAP canister purge vol-
ume control solenoid valve control value
computed by the ECM according to the
input signals.
The opening becomes larger as the
value increases.
AIR COND RLY
[ON/OFF] ×
The air conditioner relay control condi-
tion (determined by ECM according to
the input signals) is indicated.
FUEL PUMP RLY
[ON/OFF] ×
Indicates the fuel pump relay control
condition determined by ECM according
to the input signals.
Monitored item
[Unit] ECM
INPUT
SIGNALS MAIN
SIGNALS Description Remarks
EC-130Revision: November 2009
TROUBLE DIAGNOSIS
2006 QX56
LOAD SIGNALIgnition switch: ONRear window defogger switch is ON
and/or lighting switch is in 2nd.
ON
Rear window defogger switch is OFF
and lighting switch is OFF. OFF
IGNITION SW
Ignition switch: ON → OFF → ON ON → OFF → ON
HEATER FAN SW
Engine: After warming up, idle
the engine Heater fan control switch: ON
ON
Heater fan control switch: OFF OFF
BRAKE SW
Ignition switch: ON Brake pedal: Fully released
OFF
Brake pedal: Slightly depressed ON
INJ PULSE-B1
INJ PULSE-B2
Engine: After warming up
Selector lever: P or N
Air conditioner switch: OFF
No load Idle
2.0 - 2.8 msec
2,000 rpm 1.9 - 2.9 msec
IGN TIMING
Engine: After warming up
Selector lever: P or N
Air conditioner switch: OFF
No load Idle
10° - 20 ° BTDC
2,000 rpm 25° - 45 ° BTDC
CAL/LD VALUE
Engine: After warming up
Selector lever: P or N
Air conditioner switch: OFF
No load Idle
14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW
Engine: After warming up
Selector lever: P or N
Air conditioner switch: OFF
No load Idle
3.0 - 9.0 g·m/s
2,500 rpm 9.0 - 28.0 g·m/s
PURG VOL C/V
Engine: After warming up
Selector lever: P or N
Air conditioner switch: OFF
No load Idle
(Accelerator pedal: Not depressed
even slightly, after engine starting.)
0%
2,000 rpm —
AIR COND RLY
Engine: After warming up, idle
the engine Air conditioner switch: OFF
OFF
Air conditioner switch: ON
(Compressor: Operates) ON
FUEL PUMP RLY
For 1 second after turning ignition switch ON
Engine running or cranking ON
Except above conditions
OFF
VENT CONT/V
Ignition switch: ON OFF
THRTL RELAY
Ignition switch: ON ON
COOLING FAN
Engine: After warming up, idle
the engine
Air conditioner switch: OFF Engine coolant temperature: 99
°C
(210 °F) or less OFF
Engine coolant temperature: 100 °C
(212 °F) or more HI
HO2S2 HTR (B1)
HO2S2 HTR (B2)
Engine speed: Below 3,600 rpm after the following conditions are met.
–Engine: After warming up
–Keeping the engine speed between 3,500 and 4,000 rpm for 1 minute and
at idle for 1 minute under no load ON
Engine speed: Above 3,600 rpm
OFF
I/P PULLY SPD
Vehicle speed: More than 20 km/h (12 MPH) Almost the same speed as the
tachometer indication
MONITOR ITEM CONDITION SPECIFICATION
TROUBLE DIAGNOSISEC-131
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EC
Revision: November 2009 2006 QX56
*: Accelerator pedal position sensor 2 signal and throttle position sensor 2 signal are converted by ECM internally. Thus, they differ from
ECM terminals voltage signal.VEHICLE SPEED
Turn drive wheels and compare CONSULT-II value with the speedometer
indication.
Almost the same speed as the
speedometer indication
TRVL AFTER MIL
Ignition switch: ON Vehicle has traveled after MIL has
turned ON. 0 - 65,535 km
(0 - 40,723 mile)
A/F S1 HTR (B1)
A/F S1 HTR (B2)
Engine: After warming up, idle the engine 0 - 100%
AC PRESS SEN
Engine: Idle
Both A/C switch and blower fan switch: ON (Compressor operates.) 1.0 - 4.0V
VHCL SPEED SE
Turn drive wheels and compare CONSULT-II value with the speedometer
indication. Almost the same speed as the
speedometer indication
SET VHCL SPD
Engine: Running ASCD: Operating. The preset vehicle speed is
displayed.
MAIN SW
Ignition switch: ON MAIN switch: Pressed
ON
MAIN switch: Released OFF
CANCEL SW
Ignition switch: ON CANCEL switch: Pressed
ON
CANCEL switch: Released OFF
RESUME/ACC SW
Ignition switch: ON RESUME/ACCELERATE switch:
Pressed
ON
RESUME/ACCELERATE switch:
Released OFF
SET SW
Ignition switch: ON SET/COAST switch: Pressed
ON
SET/COAST switch: Released OFF
DIST SW
Ignition switch: ON DISTANCE switch: Pressed
ON
DISTANCE switch: Released OFF
BRAKE SW1
Ignition switch: ON Brake pedal: Fully released
ON
Brake pedal: Slightly depressed OFF
BRAKE SW2
Ignition switch: ON Brake pedal: Fully released
OFF
Brake pedal: Slightly depressed ON
CRUISE LAMP
Ignition switch: ON MAIN switch: Pressed at the 1st time
→
at the 2nd time ON
→ OFF
SET LAMP
MAIN switch: ON
Vehicle speed: Between 40 km/h
(25 MPH) and 144 km/h (89
MPH) ASCD: Operating
ON
ASCD: Not operating OFF
MONITOR ITEM
CONDITION SPECIFICATION
EC-502Revision: November 2009
DTC P1572 ICC BRAKE SWITCH
2006 QX56
DTC P1572 ICC BRAKE SWITCHPFP:25320
Component DescriptionUBS00L1W
When the brake pedal is depressed, ICC brake switch is turned OFF
and stop lamp switch is turned ON. ECM detects the state of the
brake pedal by this input of two kinds (ON/OFF signal).
Refer to ACS-6, "
DESCRIPTION" for the ICC function.
CONSULT-II Reference Value in Data Monitor ModeUBS00L1X
Specification data are reference values.
On Board Diagnosis LogicUBS00L1Y
This diagnosis has the one trip detection logic.
The MIL will not light up for this diagnosis.
NOTE:
If DTC P1572 is displayed with DTC P0605, first perform the trouble diagnosis for DTC P0605.
Refer to EC-457, "
DTC P0605 ECM" .
This self-diagnosis has the one trip detection logic. When malfunction A is detected, DTC is not
stored in ECM memory. And in that case, 1st trip DTC and 1st trip freeze frame data are displayed.
1st trip DTC is erased when ignition switch OFF. And even when malfunction A is detected in two
consecutive trips, DTC is not stored in ECM memory.
BBIA0470E
MONITOR ITEM CONDITIONSPECIFICATION
BRAKE SW1
(ICC brake switch)
Ignition switch: ON Brake pedal: Fully released
ON
Brake pedal: Slightly depressed OFF
BRAKE SW2
(stop lamp switch)
Ignition switch: ON Brake pedal: Fully released
OFF
Brake pedal: Slightly depressed ON
DTC No.Trouble diagnosis
name DTC detecting condition
Possible cause
P1572
1572 ICC brake switch A)
When vehicle speed is above 30 km/h (19
MPH), ON signals from the stop lamp
switch and the ICC brake switch are sent
to ECM at the same time.
Harness or connectors
(The stop lamp switch circuit is shorted.)
Harness or connectors
(The ICC brake switch circuit is shorted.)
Stop lamp switch
ICC brake switch
ICC brake hold relay
Incorrect stop lamp switch installation
Incorrect ICC brake switch installation
ECM
B)
ICC brake switch signal is not sent to ECM
for extremely long time while the vehicle is
driving
DTC P1572 ICC BRAKE SWITCHEC-503
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EC
Revision: November 2009 2006 QX56
DTC Confirmation ProcedureUBS00L1Z
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.
Procedure for malfunction B is not described here. It takes extremely long time to complete procedure for
malfunction B. By performing procedure for malfunction A, the incident that causes malfunction B can be
detected.
TESTING CONDITION:
Steps 4 and 5 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. Press MAIN switch and make sure that CRUISE lamp lights up.
4. Drive the vehicle for at least 5 consecutive seconds under the following conditions.
If 1st trip DTC is detected, go to EC-505, "
Diagnostic Procedure"
.
If 1st trip DTC is not detected, go to the following step.
5. Drive the vehicle for at least 5 consecutive seconds under the following conditions.
6. If 1st trip DTC is detected, go to EC-505, "
Diagnostic Procedure" .
WITH GST
Follow the procedure “WITH CONSULT-II” above.
VHCL SPEED SE More than 30 km/h (19 MPH)
Selector lever Suitable position
PBIB2386E
VHCL SPEED SEMore than 30 km/h (19 MPH)
Selector lever Suitable position
Driving location Depress the brake pedal for more than
five seconds so as not to come off from
the above-mentioned vehicle speed.
DTC P1572 ICC BRAKE SWITCHEC-505
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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 ProcedureUBS00L21
1. CHECK OVERALL FUNCTION-I
With CONSULT-II
1. Turn ignition switch ON.
2. Select “BRAKE SW1 ” in “DATA MONITOR” mode with CON-
SULT-II.
3. Check “BRAKE SW1 ” indication under the following conditions.
Without CONSULT-II
1. Turn ignition switch ON.
2. Check voltage between ECM terminal 108 and ground under the following conditions.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
TER-
MINAL NO. WIRE
COLOR ITEM
CONDITION DATA (DC Voltage)
101 R/W Stop lamp switch [Ignition switch: OFF]
Brake pedal: Fully released
Approximately 0V
[Ignition switch: OFF]
Brake pedal: Slightly depressed BATTERY VOLTAGE
(11 - 14V)
108 BR/W ICC brake switch [Ignition switch: ON]
Brake pedal: Slightly depressed
Approximately 0V
[Ignition switch: ON]
Brake pedal: Fully released BATTERY VOLTAGE
(11 - 14V)
CONDITION
INDICATION
Brake pedal: Slightly depressed OFF
Brake pedal: Fully released ON
SEC011D
CONDITIONVOLTAGE
Brake pedal: Slightly depressed Approximately 0V
Brake pedal: Fully released Battery voltage
MBIB0061E