2004 INFINITI QX56 display

EC-40Revision: August 2007
BASIC SERVICE PROCEDURE
2004 QX56
19. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With CONSULT-II
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect CONSULT-II to the vehicle.
7. Make sure that no (1st trip) DTC is displayed in “SELF-DIAG RESULTS” mode.
OK or NG
OK >>INSPECTION END
NG >> GO TO 21.
20. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With GST
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect GST to the vehicle.
7. Make sure that no (1st trip) DTC is displayed.
OK or NG
OK >>INSPECTION END
NG >> GO TO 21.

BASIC SERVICE PROCEDURE
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Revision: August 20072004 QX56
29. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With CONSULT-II
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect CONSULT-II to the vehicle.
7. Make sure that no (1st trip) DTC is displayed in “SELF-DIAG RESULTS” mode.
OK or NG
OK >> GO TO 4.
NG >> GO TO 31.
30. CHECK AIR FUEL RATIO (A/F) SENSOR 1 FUNCTION
With GST
1. Turn ignition switch OFF and wait at a least 10 seconds.
2. Start engine and warm it up to normal operating temperature.
3. Drive the vehicle at a speed of 80 km/h (50 MPH) for a few minutes in D position with “OD” OFF.
NOTE:
Keep the accelerator pedal as steady as possible during the cruising.
4. Set “OD” ON, then release the accelerator pedal fully until the vehicle speed decreases to 50 km/h (30
MPH).
NOTE:
Never apply brake during releasing the accelerator pedal.
5. Repeat steps 3 to 4 five times.
6. Stop the vehicle and connect GST to the vehicle.
7. Make sure that no (1st trip) DTC is displayed.
OK or NG
OK >> GO TO 4.
NG >> GO TO 31.
31. DETECT MALFUNCTIONING PART
Check the following.

Check fuel pressure regulator, and repair or replace if necessary. Refer to EC-47, "FUEL PRESSURE
CHECK" .

Check mass air flow sensor and its circuit, and repair or replace if necessary. Refer to EC-146 and EC-
154 .

Check injector and its circuit, and repair or replace if necessary. Refer to EC-595 .

Check engine coolant temperature sensor and its circuit, and repair or replace if necessary. Refer to EC-
165 and EC-178 .
OK or NG
OK >> GO TO 33.
NG >> 1. Repair or replace.
2. GO TO 32.

EC-44Revision: August 2007
BASIC SERVICE PROCEDURE
2004 QX56
32. ERASE UNNECESSARY DTC
After this inspection, unnecessary DTC might be displayed.
Erase the stored memory in ECM and TCM. Refer to EC-62, "
HOW TO ERASE EMISSION-RELATED DIAG-
NOSTIC INFORMATION" and AT- 4 0 , "HOW TO ERASE DTC" .
>> GO TO 4.
33. CHECK ECM FUNCTION
1. Substitute another known-good ECM to check ECM function. (ECM may be the cause of an incident, but
this is a rare case.)
2. Perform initialization of IVIS (NATS) system and registration of all IVIS (NATS) ignition key IDs. Refer to
BL-140, "
ECM Re-communicating Function" .
>> GO TO 4.
Accelerator Pedal Released Position LearningUBS00GZM
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 wait at least 10 seconds.
4. Turn ignition switch ON and wait at least 2 seconds.
5. Turn ignition switch OFF wait at least 10 seconds.
Throttle Valve Closed Position LearningUBS00GZN
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 LearningUBS00GZO
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)

PNP switch: ON

Electric load switch: OFF
(Air conditioner, headlamp, rear window defogger)

BASIC SERVICE PROCEDURE
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Revision: August 20072004 QX56
On vehicles equipped with daytime light systems, if the parking brake is applied before the engine
is started, the headlamp will not be illuminated.

Steering wheel: Neutral (Straight-ahead position)

Vehicle speed: Stopped

Transmission: Warmed-up
For models with CONSULT-II, drive vehicle until “FLUID TEMP SE” in “DATA MONITOR” mode of “A/T”
system indicates less than 0.9V.
For models without CONSULT-II, drive vehicle for 10 minutes.
OPERATION PROCEDURE
With CONSULT-II
1. Perform EC-44, "Accelerator Pedal Released Position Learning" .
2. Perform EC-44, "
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.
5. Select “IDLE AIR VOL LEARN” in “WORK SUPPORT” mode.
6. Touch “START” and wait 20 seconds.
7. Make sure that “CMPLT” is displayed on CONSULT-II screen. If
“CMPLT” is not displayed, Idle Air Volume Learning will not be
carried out successfully. In this case, find the cause of the inci-
dent by referring to the Diagnostic Procedure below.
8. Rev up the engine two or three times and make sure that idle
speed and ignition timing are within the specifications.
Without CONSULT-II
NOTE:

It is better to count the time accurately with a clock.

It is impossible to switch the diagnostic mode when an accelerator pedal position sensor circuit
has a malfunction.
1. Perform EC-44, "
Accelerator Pedal Released Position Learning" .
SEF 2 17 Z
SEF 4 54 Y
ITEM SPECIFICATION
Idle speed 650±50 rpm (in P or N position)
Ignition timing 15±5° BTDC (in P or N position)
MBIB0238E

ON BOARD DIAGNOSTIC (OBD) SYSTEM
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Revision: August 20072004 QX56
ON BOARD DIAGNOSTIC (OBD) SYSTEMPFP:00028
IntroductionUBS00GZQ
The ECM has an on board diagnostic system, which detects malfunctions related to engine sensors or actua-
tors. The ECM also records various emission-related diagnostic information including:
The above information can be checked using procedures listed in the table below.
×: Applicable —: Not applicable
*: When DTC and 1st trip DTC simultaneously appear on the display, they cannot be clearly distinguished from each other.
The malfunction indicator lamp (MIL) on the instrument panel lights up when the same malfunction is detected
in two consecutive trips (Two trip detection logic), or when the ECM enters fail-safe mode. (Refer to EC-77,
"Fail-safe Chart" .)
Two Trip Detection LogicUBS00GZR
When a malfunction is detected for the first time, 1st trip DTC and 1st trip Freeze Frame data are stored in the
ECM memory. The MIL will not light up at this stage. <1st trip>
If the same malfunction is detected again during the next drive, the DTC and Freeze Frame data are stored in
the ECM memory, and the MIL lights up. The MIL lights up at the same time when the DTC is stored. <2nd
trip> The “trip” in the “Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation. Specific on board diagnostic items will cause the ECM to light up or blink the MIL,
and store DTC and Freeze Frame data, even in the 1st trip, as shown below.
×: Applicable —: Not applicable
When there is an open circuit on MIL circuit, the ECM cannot warn the driver by lighting MIL up when there is
malfunction on engine control system.
Therefore, when electrical controlled throttle and part of ECM related diagnoses are continuously detected as
NG for 5 trips, ECM warns the driver that engine control system malfunctions and MIL circuit is open by means
of operating fail-safe function.
Emission-related diagnostic information SAE Mode
Diagnostic Trouble Code (DTC) Mode 3 of SAE J1979
Freeze Frame data Mode 2 of SAE J1979
System Readiness Test (SRT) code Mode 1 of SAE J1979
1st Trip Diagnostic Trouble Code (1st Trip DTC) Mode 7 of SAE J1979
1st Trip Freeze Frame data
Test values and Test limits Mode 6 of SAE J1979
Calibration ID Mode 9 of SAE J1979
DTC 1st trip DTCFreeze Frame
data1st trip Freeze
Frame dataSRT code Test value
CONSULT-II×× × × ×—
GST×× ×—××
ECM××*— ———
ItemsMIL DTC 1st trip DTC
1st trip 2nd trip
1st trip
displaying2nd trip
displaying1st trip
displaying2nd trip
display-
ing BlinkingLighting
upBlinkingLighting
up
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0308 is
being detected×———— —×—
Misfire (Possible three way catalyst
damage) — DTC: P0300 - P0308 is
being detected——×——×——
One trip detection diagnoses (Refer
to EC-8, "
INDEX FOR DTC" .)—×——×———
Except above — — —×—××—

ON BOARD DIAGNOSTIC (OBD) SYSTEM
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Revision: August 20072004 QX56
*1: 1st trip DTC No. is the same as DTC No.
*2: This number is prescribed by SAE J2012.
*3: In Diagnostic Test Mode II (Self-diagnostic results). This number is controlled by NISSAN.
*4: When the fail-safe operations for both self-diagnoses occur at the same time, the MIL illuminates.
*5: The trouble shooting for this DTC needs CONSULT-II.
*6: SRT code will not be set if the self-diagnostic result is NG.
*7: 2WD models
*8: Models with ICC system
DTC AND 1ST TRIP DTC
The 1st trip DTC (whose number is the same as the DTC number) is displayed for the latest self-diagnostic
result obtained. If the ECM memory was cleared previously, and the 1st trip DTC did not reoccur, the 1st trip
DTC will not be displayed.
If a malfunction is detected during the 1st trip, the 1st trip DTC is stored in the ECM memory. The MIL will not
light up (two trip detection logic). If the same malfunction is not detected in the 2nd trip (meeting the required
driving pattern), the 1st trip DTC is cleared from the ECM memory. If the same malfunction is detected in the
2nd trip, both the 1st trip DTC and DTC are stored in the ECM memory and the MIL lights up. In other words,
the DTC is stored in the ECM memory and the MIL lights up when the same malfunction occurs in two consec-
utive trips. If a 1st trip DTC is stored and a non-diagnostic operation is performed between the 1st and 2nd
trips, only the 1st trip DTC will continue to be stored. For malfunctions that blink or light up the MIL during the
1st trip, the DTC and 1st trip DTC are stored in the ECM memory.
Procedures for clearing the DTC and the 1st trip DTC from the ECM memory are described in EC-62, "
HOW
TO ERASE EMISSION-RELATED DIAGNOSTIC INFORMATION" .
For malfunctions in which 1st trip DTCs are displayed, refer to EC-50, "
EMISSION-RELATED DIAGNOSTIC
INFORMATION ITEMS" . These items are required by legal regulations to continuously monitor the system/
component. In addition, the items monitored non-continuously are also displayed on CONSULT-II.
NATS MALFUNCTIONP1610 -
P16151610 - 1615 — —×BL-138
P-N POS SW/CIRCUIT P1706 1706 — —×EC-546
TURBINE REV S/CIRC P1716 1716 — —×AT- 1 3 4
A/T INTERLOCK P1730 1730 — — —AT- 1 3 9
I/C SOLENOID/CIRC P1752 1752 — — —AT- 1 4 5
I/C SOLENOID FNCTN P1754 1754 — — —AT- 1 4 8
FR/B SOLENOID/CIRC P1757 1757 — — —AT- 1 5 1
FR/B SOLENOID/CIRC P1759 1759 — — —AT- 1 5 4
D/C SOLENOID/CIRC P1762 1762 — — —AT- 1 5 7
D/C SOLENOID FNCTN P1764 1764 — — —AT- 1 6 0
HLR/C SOL/CIRC P1767 1767 — — —AT- 1 6 3
HLR/C SOL FNCTN P1769 1769 — — —AT- 1 6 6
LC/B SOLENOID/CIRC P1772 1772 — — —AT- 1 6 9
LC/B SOLENOID FNCT P1774 1774 — — —AT- 1 7 2
BRAKE SW/CIRCUIT P1805 1805 — —×EC-551
APP SEN 1/CIRC P2122 2122 — — —EC-556
APP SEN 1/CIRC P2123 2123 — — —EC-556
APP SEN 2/CIRC P2127 2127 — — —EC-562
APP SEN 2/CIRC P2128 2128 — — —EC-562
TP SENSOR P2135 2135 — — —EC-569
APP SENSOR P2138 2138 — — —EC-576
Items
(CONSULT-II screen terms)DTC*
1
SRT codeTest value/
Test limit
(GST only)1st trip DTCReference
page CONSULT-II
GST*
2ECM*3

EC-54Revision: August 2007
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2004 QX56
1st trip DTC is specified in Mode 7 of SAE J1979. 1st trip DTC detection occurs without lighting up the MIL and
therefore does not warn the driver of a malfunction. However, 1st trip DTC detection will not prevent the vehi-
cle from being tested, for example during Inspection/Maintenance (I/M) tests.
When a 1st trip DTC is detected, check, print out or write down and erase (1st trip) DTC and Freeze Frame
data as specified in Work Flow procedure Step II, refer to EC-72, "
WORK FLOW" . Then perform DTC Confir-
mation Procedure or Overall Function Check to try to duplicate the malfunction. If the malfunction is dupli-
cated, the item requires repair.
How to Read DTC and 1st Trip DTC
DTC and 1st trip DTC can be read by the following methods.
With CONSULT-II
With GST
CONSULT-II or GST (Generic Scan Tool) Examples: P0340, P1148, P1706, etc.
These DTCs are prescribed by SAE J2012.
(CONSULT-II also displays the malfunctioning component or system.)
No Tools
The number of blinks of the MIL in the Diagnostic Test Mode II (Self-Diagnostic Results) indicates the DTC.
Example: 0340, 1148, 1706, etc.
These DTCs are controlled by NISSAN.

1st trip DTC No. is the same as DTC No.

Output of a DTC indicates a malfunction. However, GST or the Diagnostic Test Mode II do not indi-
cate whether the malfunction is still occurring or has occurred in the past and has returned to nor-
mal. CONSULT-II can identify malfunction status as shown below. Therefore, using CONSULT-II (if
available) is recommended.
A sample of CONSULT-II display for DTC and 1st trip DTC is shown below. DTC or 1st trip DTC of a malfunc-
tion is displayed in “SELF-DIAGNOSTIC RESULTS” mode of CONSULT-II. Time data indicates how many
times the vehicle was driven after the last detection of a DTC.
If the DTC is being detected currently, the time data will be [0].
If a 1st trip DTC is stored in the ECM, the time data will be [1t].
FREEZE FRAME DATA AND 1ST TRIP FREEZE FRAME DATA
The ECM records the driving conditions such as fuel system status, calculated load value, engine coolant tem-
perature, short term fuel trim, long term fuel trim, engine speed, vehicle speed, base fuel schedule and intake
air temperature at the moment a malfunction is detected.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data.
The data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-II or
GST. The 1st trip freeze frame data can only be displayed on the CONSULT-II screen, not on the GST. For
details, see EC-107, "
Freeze Frame Data and 1st Trip Freeze Frame Data" .
Only one set of freeze frame data (either 1st trip freeze frame data or freeze frame data) can be stored in the
ECM. 1st trip freeze frame data is stored in the ECM memory along with the 1st trip DTC. There is no priority
for 1st trip freeze frame data and it is updated each time a different 1st trip DTC is detected. However, once
freeze frame data (2nd trip detection/MIL on) is stored in the ECM memory, 1st trip freeze frame data is no
longer stored. Remember, only one set of freeze frame data can be stored in the ECM. The ECM has the fol-
lowing priorities to update the data.
PBIB09 11 E

EC-58Revision: August 2007
ON BOARD DIAGNOSTIC (OBD) SYSTEM
2004 QX56
How to Display SRT Code
WITH CONSULT-II
Selecting “SRT STATUS” in “DTC CONFIRMATION” mode with
CONSULT-II.
For items whose SRT codes are set, a “CMPLT” is displayed on the
CONSULT-II screen; for items whose SRT codes are not set,
“INCMP” is displayed.
A sample of CONSULT-II display for SRT code is shown at right.
“INCMP” means the self-diagnosis is incomplete and SRT is not set.
“CMPLT” means the self-diagnosis is complete and SRT is set.
WITH GST
Selecting MODE 1 with GST (Generic Scan Tool)
How to Set SRT Code
To set all SRT codes, self-diagnosis for the items indicated above must be performed one or more times. Each
diagnosis may require a long period of actual driving under various conditions.
WITH CONSULT-II
Perform corresponding DTC Confirmation Procedure one by one based on Performance Priority in the table
on EC-55, "
SRT Item" .
WITHOUT CONSULT-II
The most efficient driving pattern in which SRT codes can be properly set is explained on the next page. The
driving pattern should be performed one or more times to set all SRT codes.
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