engine INFINITI QX56 2004 Factory Service Manual

TROUBLE DIAGNOSIS
EC-107
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Revision: August 20072004 QX56
*: This function is not necessary in the usual service procedure.
SELF-DIAG RESULTS MODE
Self Diagnostic Item
Regarding items of DTC and 1st trip DTC, refer to EC-8, "INDEX FOR DTC" .)
Freeze Frame Data and 1st Trip Freeze Frame Data
*1: The items are the same as those of 1st trip freeze frame data.
DATA MONITOR MODE
Monitored Item
×: Applicable Freeze frame data
item*
1Description
DIAG TROUBLE
CODE
[PXXXX]

The engine control component part/control system has a trouble code, it is displayed as “PXXXX”. (Refer
to EC-8, "
INDEX FOR DTC" .)
FUEL SYS-B1

“Fuel injection system status” at the moment a malfunction is detected is displayed.

One mode in the following is displayed.
“Mode2”: Open loop due to detected system malfunction
“Mode3”: Open loop due to driving conditions (power enrichment, deceleration enleanment)
“Mode4”: Closed loop - using oxygen sensor(s) as feedback for fuel control
“Mode5”: Open loop - has not yet satisfied condition to go to closed loop FUEL SYS-B2
CAL/LD VALUE [%]

The calculated load value at the moment a malfunction is detected is displayed.
COOLANT TEMP
[°C] or [°F]

The engine coolant temperature at the moment a malfunction is detected is displayed.
L-FUEL TRM-B1 [%]

“Long-term fuel trim” at the moment a malfunction is detected is displayed.

The long-term fuel trim indicates much more gradual feedback compensation to the base fuel schedule
than short-term fuel trim. L-FUEL TRM-B2 [%]
S-FUEL TRM-B1 [%]

“Short-term fuel trim” at the moment a malfunction is detected is displayed.

The short-term fuel trim indicates dynamic or instantaneous feedback compensation to the base fuel
schedule. S-FUEL TRM-B2 [%]
ENGINE SPEED
[rpm]

The engine speed at the moment a malfunction is detected is displayed.
VEHICL SPEED
[km/h] or [mph]

The vehicle speed at the moment a malfunction is detected is displayed.
B/FUEL SCHDL
[msec]

The base fuel schedule at the moment a malfunction is detected is displayed.
INT/A TEMP SE
[°C] or [°F]

The intake air temperature at the moment a malfunction is detected is displayed.
Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
ENG SPEED [rpm]××

Indicates the engine speed computed from the
signal of the crankshaft position sensor (POS)
and camshaft position sensor (PHASE).

Accuracy becomes poor if engine
speed drops below the idle rpm.

If the signal is interrupted while the
engine is running, an abnormal value
may be indicated.
MAS A/F SE-B1 [V]××

The signal voltage of the mass air flow sensor
is displayed.
When the engine is stopped, a certain
value is indicated.
B/FUEL SCHDL
[msec]×

“Base fuel schedule” indicates the fuel injec-
tion pulse width programmed into ECM, prior
to any learned on board correction.

EC-108Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
A/F ALPHA-B1 [%]×

The mean value of the air-fuel ratio feedback
correction factor per cycle is indicated.

When the engine is stopped, a certain
value is indicated.

This data also includes the data for the
air-fuel ratio learning control. A/F ALPHA-B2 [%]×
COOLAN TEMP/S
[°C] or [°F]××

The engine coolant temperature (determined
by the signal voltage of the engine coolant
temperature sensor) is displayed.

When the engine coolant temperature
sensor is open or short-circuited, ECM
enters fail-safe mode. The engine
coolant temperature determined by the
ECM is displayed.
A/F SEN1 (B1) [V]××

The A/F signal computed from the input signal
of the A/F sensor 1 is displayed.
A/F SEN1 (B2) [V]×
HO2S2 (B1) [V]×

The signal voltage of the heated oxygen sen-
sor 2 is displayed.
HO2S2 (B2) [V]×
HO2S2 MNTR (B1)
[RICH/LEAN]×

Display of heated oxygen sensor 2 signal:
RICH: Means the amount of oxygen after
three way catalyst is relatively small.
LEAN: Means the amount of oxygen after
three way catalyst is relatively large.

When the engine is stopped, a certain
value is indicated.
HO2S2 MNTR (B2)
[RICH/LEAN]×
VHCL SPEED SE
[km/h] or [mph]××

The vehicle speed computed from the vehicle
speed signal sent from combination meter is
displayed.
BATTERY VOLT
[V]××

The power supply voltage of ECM is dis-
played.
ACCEL SEN 1 [V]××

The accelerator pedal position sensor signal
voltage is displayed.
ACCEL SEN 2 [V]×
Accelerator pedal position sensor 2
signal is converted by ECM internally.
Thus, it differs from ECM terminal volt-
age signal.
THRTL SEN 1 [V]××

The throttle position sensor signal voltage is
displayed.
THRTL SEN 2 [V]×
Throttle position sensor 2 signal is
converted by ECM internally. Thus, it
differs from ECM terminal voltage sig-
nal.
FUEL T/TEMP SE
[°C] or [°F]×

The fuel temperature (determined by the sig-
nal voltage of the fuel tank temperature sen-
sor) is displayed.
INT/A TEMP SE
[°C] or [°F]××

The intake air temperature (determined by the
signal voltage of the intake air temperature
sensor) is indicated.
EVAP SYS PRES
[V]×

The signal voltage of EVAP control system
pressure sensor is displayed.
FUEL LEVEL SE
[V]×

The signal voltage of the fuel level sensor is
displayed.
START SIGNAL
[ON/OFF]××

Indicates start signal status [ON/OFF] com-
puted by the ECM according to the signals of
engine speed and battery voltage.
After starting the engine, [OFF] is dis-
played regardless of the starter signal.
CLSD THL POS
[ON/OFF]××

Indicates idle position [ON/OFF] computed by
ECM according to the accelerator pedal posi-
tion sensor signal.
AIR COND SIG
[ON/OFF]××

Indicates [ON/OFF] condition of the air condi-
tioner switch as determined by the air condi-
tioner signal. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS
EC-109
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Revision: August 20072004 QX56P/N POSI SW
[ON/OFF]××
Indicates [ON/OFF] condition from the park/
neutral position (PNP) switch signal.
PW/ST SIGNAL
[ON/OFF]××

[ON/OFF] condition of the power steering sys-
tem (determined by the signal voltage of the
power steering pressure sensor signal) is indi-
cated.
LOAD SIGNAL
[ON/OFF]××

Indicates [ON/OFF] condition from the electri-
cal 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 ignition
switch signal.
HEATER FAN SW
[ON/OFF]

Indicates [ON/OFF] condition from the 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 volume
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 condition
(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 sig-
nals.
VENT CONT/V
[ON/OFF]

The control condition of the EVAP canister
vent control valve (determined by ECM
according to the input signals) is indicated.
ON: Closed
OFF: Open
THRTL RELAY
[ON/OFF]

Indicates the throttle control motor relay con-
trol condition determined by the ECM accord-
ing to the input signals.
COOLING FAN
[HI/OFF]

The control condition of the cooling fan (deter-
mined by ECM according to the input signals)
is indicated.
ON: Operating
OFF: Stop Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

EC-110Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
HO2S2 HTR (B1)
[ON/OFF]
Indicates [ON/OFF] condition of heated oxy-
gen sensor 2 heater determined by ECM
according to the input signals. HO2S2 HTR (B2)
[ON/OFF]
I/P PULLY SPD
[rpm]

Indicates the engine speed computed from the
turbine revolution sensor signal.
VEHICLE SPEED
[km/h] or [MPH]

Indicates the vehicle speed computed from
the revolution sensor signal.
IDL A/V LEARN
[YET/CMPLT]

Display the condition of idle air volume learn-
ing
YET: Idle air volume learning has not been
performed yet.
CMPLT: Idle air volume learning has already
been performed successfully.
TRVL AFTER MIL
[km] or [mile]

Distance traveled while MIL is activated.
A/F S1 HTR (B1)
[%]

Indicates A/F sensor 1 heater control value
computed by the ECM according to the input
signals.

The current flow to the heater becomes larger
as the value increases. A/F S1 HTR (B2)
[%]
AC PRESS SEN
[V]

The signal voltage from the refrigerant pres-
sure sensor is displayed.
VHCL SPEED SE
[km/h] or [mph]

The vehicle speed computed from the vehicle
speed signal sent from TCM is displayed.
SET VHCL SPD
[km/h] or [mph]

The preset vehicle speed is displayed.
MAIN SW
[ON/OFF]

Indicates [ON/OFF] condition from ON/
OFF(MAIN) switch signal.
CANCEL SW
[ON/OFF]

Indicates [ON/OFF] condition from CANCEL
switch signal.
RESUME/ACC SW
[ON/OFF]

Indicates [ON/OFF] condition from ACCEL/
RESUME switch signal.
SET SW
[ON/OFF]

Indicates [ON/OFF] condition from COAST/
SET switch signal.
DIST SW
[ON/OFF]

Indicates [ON/OFF] condition from DISTANCE
switch signal.
BRAKE SW1 SW
[ON/OFF]

Indicates [ON/OFF] condition from ASCD
brake switch signal.
BRAKE SW2 SW
[ON/OFF]

Indicates [ON/OFF] condition of stop lamp
switch signal.
VHCL SPD CUT
[NON/CUT]

Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed increased to excessively
high compared with the ASCD set speed, and
ASCD operation is cut off.
LOW SPEED CUT
[NON/CUT]

Indicates the vehicle cruise condition.
NON: Vehicle speed is maintained at the
ASCD set speed.
CUT: Vehicle speed decreased to excessively
low compared with the ASCD set speed, and
ASCD operation is cut off. Monitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks

TROUBLE DIAGNOSIS
EC-111
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Revision: August 20072004 QX56
NOTE:

Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.
DATA MONITOR (SPEC) MODE
Monitored Item
NOTE:
Any monitored item that does not match the vehicle being diagnosed is deleted from the display automatically.AT O D M O N I T O R
[ON/OFF]

Indicates [ON/OFF] condition of A/T O/D
according to the input signal from TCM.
AT OD CANCEL
[ON/OFF]

Indicates [ON/OFF] condition of A/T O/D can-
cel signal from TCM.
CRUISE LAMP
[ON/OFF]

Indicates [ON/OFF] condition of CRUISE lamp
determined by the ECM according to the input
signals.
SET LAMP
[ON/OFF]

Indicates [ON/OFF] condition of SET lamp
determined by the ECM according to the input
signals.
Voltage [V]

Voltage, frequency, duty cycle or pulse width
measured by the probe.

Only “#” is displayed if item is unable
to be measured.

Figures with “#”s are temporary ones.
They are the same figures as an actual
piece of data which was just previously
measured. Frequency [msec],
[Hz] or [%]
DUTY-HI
DUTY-LOW
PLS WIDTH-HI
PLS WIDTH-LOWMonitored item
[Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
Monitored item [Unit]ECM
INPUT
SIG-
NALSMAIN
SIG-
NALSDescription Remarks
ENG SPEED [rpm]××

Indicates the engine speed computed
from the signal of the crankshaft position
sensor (POS).
MAS A/F SE-B1 [V]××

The signal voltage of the mass air flow
sensor specification is displayed.
When engine is running specification
range is indicated.
B/FUEL SCHDL
[msec]×

“Base fuel schedule” indicates the fuel
injection pulse width programmed into
ECM, prior to any learned on board cor-
rection.

When engine is running specification
range is indicated.
A/F ALPHA-B1 [%]
A/F ALPHA-B2 [%]×

The mean value of the air-fuel ratio feed-
back correction factor per cycle is indi-
cated.
When engine is running specification
range is indicated.

This data also includes the data for the
air-fuel ratio learning control.

EC-112Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
ACTIVE TEST MODE
Test Item
*: Leaving cooling fan OFF with CONSULT-II while engine is running may cause the engine to overheat.
DTC & SRT CONFIRMATION MODE
SRT STATUS Mode
For details, refer to EC-55, "SYSTEM READINESS TEST (SRT) CODE" .
SRT Work Support Mode
This mode enables a technician to drive a vehicle to set the SRT while monitoring the SRT status.
TEST ITEM CONDITION JUDGEMENT CHECK ITEM (REMEDY)
FUEL INJEC-
TION

Engine: Return to the original
trouble condition

Change the amount of fuel injec-
tion using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Fuel injector

Air fuel ratio (A/F) sensor 1
IGNITION TIM-
ING

Engine: Return to the original
trouble condition

Timing light: Set

Retard the ignition timing using
CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Perform Idle Air Volume Learning.
POWER BAL-
ANCE

Engine: After warming up, idle
the engine.

A/C switch OFF

Shift lever N

Cut off each injector signal one at
a time using CONSULT-II.Engine runs rough or dies.

Harness and connectors

Compression

Fuel injector

Power transistor

Spark plug

Ignition coil
COOLING FAN*

Ignition switch: ON

Turn the cooling fan ON and OFF
using CONSULT-II.Cooling fan moves and stops.

Harness and connectors

Cooling fan motor

IPDM E/R
ENG COOLANT
TEMP

Engine: Return to the original
trouble condition

Change the engine coolant tem-
perature using CONSULT-II.If trouble symptom disappears, see
CHECK ITEM.

Harness and connectors

Engine coolant temperature sen-
sor

Fuel injector
FUEL PUMP
RELAY

Ignition switch: ON (Engine
stopped)

Turn the fuel pump relay ON and
OFF using CONSULT-II and lis-
ten to operating sound.Fuel pump relay makes the operat-
ing sound.
Harness and connectors

Fuel pump relay
PURG VOL
CONT/V

Engine: After warming up, run
engine at 1,500 rpm.

Change the EVAP canister purge
volume control solenoid valve
opening percent using CON-
SULT-II.Engine speed changes according to
the opening percent.
Harness and connectors

Solenoid valve
FUEL/T TEMP
SEN

Change the fuel tank temperature using CONSULT-II.
VENT CON-
TROL/V

Ignition switch: ON (Engine
stopped)

Turn solenoid valve ON and OFF
with the CONSULT-II and listen
to operating sound.Solenoid valve makes an operating
sound.
Harness and connectors

Solenoid valve

EC-116Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
Generic Scan Tool (GST) FunctionUBS00H06
DESCRIPTION
Generic Scan Tool (OBDII scan tool) complying with SAE J1978 has
8 different functions explained below.
ISO9141 is used as the protocol.
The name “GST” or “Generic Scan Tool” is used in this service man-
ual.
FUNCTION
INSPECTION PROCEDURE
1. Turn ignition switch OFF.
SEF 1 39 P
Diagnostic test mode Function
MODE 1 READINESS TESTSThis mode gains access to current emission-related data values, including analog inputs
and outputs, digital inputs and outputs, and system status information.
MODE 2 (FREEZE DATA)This mode gains access to emission-related data value which were stored by ECM during
the freeze frame. For details, refer to EC-54, "
FREEZE FRAME DATA AND 1ST TRIP
FREEZE FRAME DATA" .
MODE 3 DTCsThis mode gains access to emission-related power train trouble codes which were stored
by ECM.
MODE 4 CLEAR DIAG INFOThis mode can clear all emission-related diagnostic information. This includes:

Clear number of diagnostic trouble codes (MODE 1)

Clear diagnostic trouble codes (MODE 3)

Clear trouble code for freeze frame data (MODE 1)

Clear freeze frame data (MODE 2)

Reset status of system monitoring test (MODE 1)

Clear on board monitoring test results (MODE 6 and 7)
MODE 6 (ON BOARD TESTS)This mode accesses the results of on board diagnostic monitoring tests of specific com-
ponents/systems that are not continuously monitored.
MODE 7 (ON BOARD TESTS)This mode enables the off board test drive to obtain test results for emission-related pow-
ertrain components/systems that are continuously monitored during normal driving condi-
tions.
MODE 8 —This mode can close EVAP system in ignition switch ON position (Engine stopped). When
this mode is performed, the following parts can be opened or closed.

EVAP canister vent control valve open
In the following conditions, this mode cannot function.

Low ambient temperature

Low battery voltage

Engine running

Ignition switch OFF

Low fuel temperature

Too much pressure is applied to EVAP system
MODE 9 (CALIBRATION ID)This mode enables the off-board test device to request specific vehicle information such
as Vehicle Identification Number (VIN) and Calibration IDs.

EC-118Revision: August 2007
TROUBLE DIAGNOSIS
2004 QX56
CONSULT-II Reference Value in Data MonitorUBS00H07
Remarks:

Specification data are reference values.

Specification data are output/input values which are detected or supplied by the ECM at the connector.
* Specification data may not be directly related to their components signals/values/operations.
i.e. Adjust ignition timing with a timing light before monitoring IGN TIMING, because the monitor may show the specification data i n
spite of the ignition timing not being adjusted to the specification data. This IGN TIMING monitors the data calculated by the ECM
according to the signals input from the camshaft position sensor and other ignition timing related sensors.
MONITOR ITEM CONDITION SPECIFICATION
ENG SPEED

Run engine and compare the CONSULT-II value with tachometer indica-
tion.Almost the same speed as the
tachometer indication.
MAS A/F SE-B1

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

no loadIdle Approx. 1.1 - 1.4V
2,500 rpm Approx. 1.7 - 2.0V
B/FUEL SCHDL

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

no loadIdle 3.0 - 4.2 msec
2,000 rpm 3.0 - 4.2 msec
A/F ALPHA-B1
A/F ALPHA-B2

Engine: After warming upMaintaining engine speed at 2,000
rpm54% - 155%
COOLAN TEMP/S

Engine: After warming up More than 70°C (158°F)
A/F SEN1 (B1)
A/F SEN1 (B2)

Engine: After warming upMaintaining engine speed at 2,000
rpmFluctuated around 1.5V
HO2S2 (B1)
HO2S2 (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.0 - 0.3V ←→ Approx. 0.6 -
1.0V
HO2S2 MNTR (B1)
HO2S2 MNTR (B2)

Warm-up condition

After keeping engine speed
between 3,500 and 4,000 rpm for
1 minute and at idle for 1 minute
under no load.Revving engine from idle to 3,000 rpm
quickly.LEAN ←→ RICH
VEH SPEED SE

Turn drive wheels and compare the CONSULT-II value with speedometer
indication.Almost the same speed as the
speedometer indication
BATTERY VOLT

Ignition switch: ON (Engine stopped) 11 - 14V
ACCEL SEN1

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.5 - 1.0V
Accelerator pedal: Fully depressed 4.0 - 4.7V
ACCEL SEN2*

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released 0.3 - 1.2V
Accelerator pedal: Fully depressed 3.9 - 4.8V
THRTL SEN1
THRTL SEN2*

Ignition switch: ON
(Engine stopped)

Shift lever: DAccelerator pedal: Fully released More than 0.36V
Accelerator pedal: Fully depressed Less than 4.75V
EVAP SYS PRES

Ignition switch: ON Approx. 1.8 - 4.8V
START SIGNAL

Ignition switch: ON → START → ON OFF → ON → OFF
CLSD THL POS

Ignition switch: ON
(Engine stopped)Accelerator pedal: Fully released ON
Accelerator pedal: Slightly depressed OFF
AIR COND SIG

Engine: After warming up, idle
the engineAir conditioner switch: OFF OFF
Air conditioner switch: ON
(Compressor operates.)ON
P/N POSI SW

Ignition switch: ONShift lever: P or N ON
Shift lever: Except above OFF

TROUBLE DIAGNOSIS
EC-119
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Revision: August 20072004 QX56
PW/ST SIGNAL
Engine: After warming up, idle
the engineSteering wheel is in neutral position.
(Forward direction)OFF
Steering wheel is turned. ON
LOAD SIGNAL

Ignition 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 engineHeater fan is operating. ON
Heater fan is not operating OFF
BRAKE SW

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
INJ PULSE-B1
INJ PULSE-B2

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

no loadIdle 2.0 - 2.8 msec
2,000 rpm 1.9 - 2.9 msec
IGN TIMING

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

no loadIdle 14° - 18° BTDC
2,000 rpm 25° - 45° BTDC
CAL/LD VALUE

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

no loadIdle 14% - 33%
2,500 rpm 12% - 25%
MASS AIRFLOW

Engine: After warming up

Air conditioner switch: OFF

Shift lever: N

no loadIdle 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

Air conditioner switch: OFF

Shift lever: N

no loadIdle
(Accelerator pedal is not depressed
even slightly, after starting engine)0%
2,000 rpm —
AIR COND RLY

Engine: After warming up, idle
the engineAir 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 crankingON

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: OFFEngine coolant temperature is 99°C
(210°F) or lessOFF
Engine coolant temperature is
between 100°C (212°F) and 104°C
(219°F) at vehicle speed less than 40
km/h (25 MPH)ON
Engine coolant temperature is 105°C
(221°F) or moreON MONITOR ITEM CONDITION SPECIFICATION

EC-120Revision: August 2007
TROUBLE DIAGNOSIS
2004 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.HO2S2 HTR (B1)
HO2S2 HTR (B2)

Engine speed is 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 loadON

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
VEHICLE SPEED

Turn drive wheels and compare the CONSULT-II value with speedometer
indication.Almost the same speed as the
speedometer indication
TRVL AFTER MIL

Ignition switch: ONVehicle has traveled after MIL has
turned ON.0 - 65,535 km
(0 - 40,723 miles)
AC PRESS SEN

Ignition switch: ON (Engine stopped) Approx. 0V

Engine: Idle

Air conditioner switch: OFF1.0 - 4.0V
VEH SPEED SE

Turn drive wheels and compare the CONSULT-II value with 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: ONON/OFF(MAIN) switch: Pressed ON
ON/OFF(MAIN) switch: Released OFF
CANCEL SW

Ignition switch: ONCANCEL switch: Pressed ON
CANCEL switch: Released OFF
RESUME/ACC SW

Ignition switch: ONACCEL/RESUME switch: Pressed ON
ACCEL/RESUME switch: Released OFF
SET SW

Ignition switch: ONCOAST/SET switch: Pressed ON
COAST/SET switch: Released OFF
DIST SW

Ignition switch: ONDISTANCE switch: Pressed ON
DISTANCE switch: Released OFF
BRAKE SW1

Ignition switch: ONBrake pedal: Fully released ON
Brake pedal: Slightly depressed OFF
BRAKE SW2

Ignition switch: ONBrake pedal: Fully released OFF
Brake pedal: Slightly depressed ON
CRUISE LAMP

Ignition switch: ONON/OFF(MAIN) switch: Pressed at the
1st time → at the 2nd timeON → OFF
SET LAMP

CRUISE switch: ON

When vehicle switch is between
40 km/h (25 MPH) and 144 km/h
(89 MPH).COAST/SET switch: Pressed ON
COAST/SET switch: Released OFF MONITOR ITEM CONDITION SPECIFICATION