2008 INFINITI QX56 instrument panel

TM-30
< FUNCTION DIAGNOSIS >
ON BOARD DIAGNOSTIC (OBD) SYSTEM
ON BOARD DIAGNOSTIC (OBD) SYSTEM
IntroductionINFOID:0000000001604002
The A/T system has two self-diagnostic systems.
The first is the emission-related on board diagnostic syst em (OBD-II) performed by the TCM in combination
with the ECM. The malfunction is indicated by the MI L (malfunction indicator lamp) and is stored as a DTC in
the ECM memory but not the TCM memory.
The second is the TCM original self-diagnosis indicated by the A/T CHECK indicator lamp. The malfunction is
stored in the TCM memory. The detected items are ov erlapped with OBD-II self-diagnostic items. For detail,
refer to TM-32, "
CONSULT-III Function (TRANSMISSION)".
OBD-II Function for A/T SystemINFOID:0000000001604003
The ECM provides emission-related on board diagnostic (O BD-II) functions for the A/T system. One function
is to receive a signal from the TCM used with OBD-relat ed parts of the A/T system. The signal is sent to the
ECM when a malfunction occurs in the corresponding OBD-re lated part. The other function is to indicate a
diagnostic result by means of the MIL (malfunction indi cator lamp) on the instrument panel. Sensors, switches
and solenoid valves are used as sensing elements.
The MIL automatically illuminates in One or Two Trip Detection Logic when a malfunction is sensed in relation
to A/T system parts.
One or Two Trip Detection Logic of OBD-IIINFOID:0000000001604004
ONE TRIP DETECTION LOGIC
If a malfunction is sensed during the first test drive, the MIL will illuminate and the malfunction will be stored in
the ECM memory as a DTC. The TCM is not provided with such a memory function.
TWO TRIP DETECTION LOGIC
When a malfunction is sensed during the first test drive, it is stored in the ECM memory as a 1st trip DTC
(diagnostic trouble code) or 1st trip freeze frame data. At this point, the MIL will not illuminate. — 1st Trip
If the same malfunction as that experienced during the fi rst test drive is sensed during the second test drive,
the MIL will illuminate. — 2nd Trip
The “Trip” in the “One or Two Trip Detection Logic” means a driving mode in which self-diagnosis is performed
during vehicle operation.
OBD-II Diagnostic Trouble Code (DTC)INFOID:0000000001604005
HOW TO READ DTC AND 1ST TRIP DTC
DTC and 1st trip DTC can be read by the following methods.
( with CONSULT-III or GST) CONSULT-III or GST (Generic Scan Tool) Examples: P0705, P0720 etc.
These DTC are prescribed by SAE J2012.
(CONSULT-III also displays the malfunctioning component or system.)
• 1st trip DTC No. is the same as DTC No.
• Output of the diagnostic troubl e code indicates that the indicated circuit has a malfunction. How-
ever, in case of the Mode II and GST, they do not indicate whether the malfunction is still occurring or
occurred in the past and returned to normal.
CONSULT-III can identify them as shown below, therefore, CONSULT-III (if available) is recom-
mended.
Freeze Frame Data and 1st Trip Freeze Frame Data
The ECM has a memory function, which stores the driv ing condition such as fuel system status, calculated
load value, engine coolant temperatur e, short term fuel trim, long term fuel trim, engine speed and vehicle
speed at the moment the ECM detects a malfunction.
Data which are stored in the ECM memory, along with the 1st trip DTC, are called 1st trip freeze frame data,
and the data, stored together with the DTC data, are called freeze frame data and displayed on CONSULT-III
or GST. The 1st trip freeze frame data can only be disp layed on the CONSULT-III screen, not on the GST. For
detail, refer to TM-30
.
Only one set of freeze frame data (either 1st trip freeze frame data of 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
Revision: March 2010 2008 QX56

ON BOARD DIAGNOSTIC (OBD) SYSTEMTM-31
< FUNCTION DIAGNOSIS >
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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.
Both 1st trip freeze frame data and freeze frame data (along with the DTC) are cleared when the ECM mem-
ory is erased.
HOW TO ERASE DTC
The diagnostic trouble code can be erased by CONSULT- III, GST or ECM DIAGNOSTIC TEST MODE as
described following.
• If the battery cable is disconnected, the diagnostic trouble code will be lost within 24 hours.
• When you erase the DTC, using CONSULT-III or GS T is easier and quicker than switching the mode
selector on the ECM.
The following emission-related diagnostic information is cleared from the ECM memory when erasing DTC
related to OBD-II. For details, refer to EC-42, "
Emission-related Diagnostic Information".
• Diagnostic trouble codes (DTC)
• 1st trip diagnostic trouble codes (1st trip DTC)
• Freeze frame data
• 1st trip freeze frame data
• System readiness test (SRT) codes
• Test values
HOW TO ERASE DTC (WITH CONSULT-III)
1. The emission related diagnostic information in the TCM and ECM can be er\
ased by selectioning "ALL
ERASE" in the "Description" of "F INAL CHECK" mode with CONSULT-III.
HOW TO ERASE DTC (WITH GST)
1. If the ignition switch stays “ON” after repair work, be sure to turn ignition switch “OFF” once. Wait at least
10 seconds and then turn it “ON” (engine stopped) again.
2. Select Mode 4 with the Generic Scan Tool (GST). For details refer to EC-72, "
Generic Scan Tool (GST)
Function".
HOW TO ERASE DTC (NO TOOLS)
1. Disconnect battery for 24 hours.
2. Reconnect battery.
Malfunction Indicator Lamp (MIL)INFOID:0000000001604006
DESCRIPTION
The MIL is located on the instrument panel.
1. The MIL will light up when the ignition switch is turned “ON” with-
out the engine running. This is a bulb check.
• If the MIL does not light up, refer to EC-55, "
Malfunction Indicator
Lamp (MIL)".
2. When the engine is start ed, the MIL should go off.
If the MIL remains on, the on board diagnostic system has
detected an engine system malfunction.
Priority Items
1 Freeze frame data Misfire — DTC: P0300 - P0306 Fuel Injection System Function — DTC: P0171, P0172, P0174, P0175
2 Except the above items (Includes A/T related items)
3 1st trip freeze frame data
SEF217U
Revision: March 2010 2008 QX56

VTL-6
< ON-VEHICLE MAINTENANCE >
IN-CABIN MICROFILTER
ON-VEHICLE MAINTENANCE
IN-CABIN MICROFILTER
Removal and InstallationINFOID:0000000001516602
REPLACEMENT PROCEDURE
1. Remove the glove box assembly from the instrument panel. Refer to IP-17, "Removal and Installation".
2. Remove the screw and remove the in-cabin microfilter cover as shown.
3. Remove the two in-cabin microf ilters from the front heater and
cooling unit assembly housing.
4. Insert the first new in-cabin micr ofilter into the front heater and
cooling unit assembly housing and slide it over to the right.
Insert the second new in-cabin mi crofilter into the front heater
and cooling unit assembly housing as shown.
NOTE:
The in-cabin microfilters are marked with air flow arrows. The
end of the microfilter with the arro w should face the rear of the
vehicle. The arrows should point downward.
5. Install the in-cabin microfilter cover.
6. Install the glove box assembly in the instrument panel. Refer to IP-17, "
Removal and Installation".
7. Fill out the date information on the small replac ement label and attach it to the glove box lid.
LJIA0134E
LJIA0148E
LJIA0134E
Revision: March 2010 2008 QX56

CONTROL UNITVTL-7
< ON-VEHICLE REPAIR >
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ON-VEHICLE REPAIR
CONTROL UNIT
Removal and InstallationINFOID:0000000001516603
A/C and AV SWITCH ASSEMBLY
Removal and Installation
The front A/C switch is integrated into the A/C and AV swit ch assembly in cluster lid C in the instrument panel.
Refer to AV-164, "
Removal and Installation".
A/C AUTO AMP.
Removal
1. Remove the display unit. Refer to AV-166, "Removal and Installation".
2. Remove the four screws (A) and remove the A/C auto amp. (1) from the back of the display unit (2).
Installation
Installation is in the reverse order of removal.
REAR AIR CONTROL (FRONT)
Removal
1. Remove the front roof console finisher from the headlining. Refer to INT-17, "Removal and Installation".
2. Remove the three screws (A) and remove the rear air control (front) (1).
Installation
Installation is in the reverse order of removal.
REAR AIR CONTROL (REAR)
Removal
1. Remove the rear roof console finisher from the headlining. Refer to INT-17, "Removal and Installation".
ALIIA0063ZZ
ALIIA0058ZZ
Revision: March 2010 2008 QX56

IN-VEHICLE SENSORVTL-9
< ON-VEHICLE REPAIR >
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IN-VEHICLE SENSOR
Removal and InstallationINFOID:0000000001516604
REMOVAL
1. Remove the lower instrument panel LH. Refer to IP-11, "Exploded View".
2. Remove the two screws (A) and remove the in-vehicle sensor (1).
INSTALLATION
Installation is in the reverse order of removal.
ALIIA0060ZZ
Revision: March 2010 2008 QX56

VTL-10
< ON-VEHICLE REPAIR >
OPTICAL SENSOR
OPTICAL SENSOR
Removal and InstallationINFOID:0000000001516605
REMOVAL
1. Remove the defroster grille from the instrument panel. Refer to VTL-33, "Removal and Installation".
2. Disconnect the optical sensor connector (2).
3. Twist the optical sensor (1) counter clockwise to remove it from the defroster grille.
INSTALLATION
Installation is in the reverse order of removal.
ALIIA0061ZZ
Revision: March 2010 2008 QX56

INTAKE SENSORVTL-11
< ON-VEHICLE REPAIR >
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INTAKE SENSOR
Removal and InstallationINFOID:0000000001516606
REMOVAL
1. Remove the instrument panel. Refer to IP-12, "Removal and Installation".
2. Disconnect the intake sensor electrical connector. NOTE:
The intake sensor is located on the top of the front heater and
cooling unit assembly next to the A/C evaporator cover.
3. Twist the intake sensor to remove the intake sensor from the front heater and cooling unit assembly.
INSTALLATION
Installation is in the reverse order of removal.
LJIA0133E
Revision: March 2010 2008 QX56

VTL-14
< ON-VEHICLE REPAIR >
IN-CABIN MICROFILTER
IN-CABIN MICROFILTER
Removal and InstallationINFOID:0000000001516609
REPLACEMENT PROCEDURE
1. Remove the glove box assembly from the instrument panel. Refer to IP-17, "Removal and Installation".
2. Remove the screw and remove the in-cabin microfilter cover.
3. Remove the in-cabin microfilters from the front heater and cool- ing unit assembly housing.
4. Insert the first new in-cabin micr ofilter into the front heater and
cooling unit assembly housing and slide it over to the right.
Insert the second new in-cabin mi crofilter into the front heater
and cooling unit assembly housing.
NOTE:
The in-cabin microfilters are marked with air flow arrows. The
end of the microfilter with the arro w should face the rear of the
vehicle. The arrows should point downward.
5. Install the in-cabin microfilter cover.
6. Install the glove box assembly in the instrument panel. Refer to IP-17, "
Removal and Installation".
7. Fill out the date information on the sm all replacement label and attach it to the inside of the glove box lid.
LJIA0134E
LJIA0148E
LJIA0134E
Revision: March 2010 2008 QX56