2008 INFINITI QX56 fuel

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
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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
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TM-174
< PRECAUTION >
PRECAUTIONS
5. When the repair work is completed, return the ignition switch to the ″LOCK ″ position before connecting
the battery cables. (At this time, the steering lock mechanism will engage.)
6. Perform a self-diagnosis check of a ll control units using CONSULT-III.
Precaution for On Board Diagnosis (OBD) System of A/T and EngineINFOID:0000000001531485
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:
• Be sure to turn the ignition switch “OFF” and disconnect the negative battery cable before any repair
or inspection work. The open/short circuit of related switches, sensors, solenoid valves, etc. Will
cause the MIL to light up.
• Be sure to connect and lock the connectors secure ly after work. A loose (unlocked) connector will
cause the MIL to light up due to an open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)
• Be sure to route and secure th e harnesses properly after work. Interference of the harness with a
bracket, etc. May cause the MIL to light up due to a short circuit.
• Be sure to connect rubber tubes properly afte r work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to a malfunction of the EGR system or fuel injection system, etc.
• Be sure to erase the unnecessary malfunction informa tion (repairs completed) from the TCM and
ECM before returning the vehicle to the customer.
PrecautionINFOID:0000000001531486
NOTE:
If any malfunctions occur in the RE5R05A model tr ansmission, replace the entire transmission assem-
bly.
• Before connecting or disconn ecting the TCM harness connec-
tor, turn ignition switch “O FF” and disconnect negative bat-
tery cable. Because battery voltage is applied to TCM even if
ignition switch is turned “OFF”.
• After performing each TROUBLE DIAGNOSIS, perform “DTC
(Diagnostic Trouble Code) CONFIRMATION PROCEDURE”.
If the repair is completed the DTC should not be displayed in the
“DTC CONFIRMATION PROCEDURE”.
• Always use the specified brand of ATF. Refer to MA-12, "
Fluids and Lubricants".
• Use paper rags not cloth rags during work.
• After replacing the ATF, dispose of the waste oil using the methods prescribed by law, ordinance, etc.
• Before proceeding with disassembly, thoroughly clean the outside of the transmission. It is important to pre- vent the internal parts from becoming cont aminated by dirt or other foreign matter.
• Disassembly should be done in a clean work area.
• Use lint-free cloth or towels for wiping parts clean. Common shop rags can leave fibers that could interfere
with the operation of the transmission.
• Place disassembled parts in order for easier and proper assembly.
SEF289H
SEF217U
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DIAGNOSIS SYSTEM (METER)WCS-13
< FUNCTION DIAGNOSIS >
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CONSULT-III Function (METER/M&A)INFOID:0000000004872661
CONSULT-III can display each diagnostic item us ing the diagnostic test modes shown following.
SELF-DIAG RESULTS
Display Item List
Refer to MWI-62, "DTC Index".
DATA MONITOR
Display Item List
Switch pressed
(3 times) Sc1 XX through Epr XXDisplays 8 bit software
configuration value in Hex
format
Switch pressed 1nF XXDisplays 8-bit market info
value in Hex format. $31 = USA
$2A = Canada
Switch pressed
(3 times) cYL XX through tF N/A
Switch pressed XXXXX “Corrected” speed value
in hundredths of MPH.
Gauge indication may be
slightly higher. This is nor-
mal.Will display “-----” if message is not
received. Will display “99999” if
data received is invalid.
Switch pressed XXXXX “Corrected” speed value
in hundredths of KPH.
Gauge indication may be
slightly different. This is
normal.Will display “-----” if message is not
received. Will display “99999” if
data received is invalid.
Switch pressed t XXXX Tachometer value in
RPM. Gauge indication
may be higher at higher
RPM. This is normal.Will display “-----” if message is not
received.
Switch pressed F1XXXX Present fuel level A/D in-
put. This input represents
fuel sender input.000-009 = Short circuit
010-254 = Normal range
255 = Open circuit
Switch pressed F2XXX Present FLPS.010-254 = Normal range
Switch pressed XXXC Last temperature gauge
input value in degrees C.
Temperature gauge indi-
cates present tempera-
ture per indication
standard.Will display “---”C if
message is not
received.
Will display “999” if data received
is invalid.
High = 130 deg C
Normal = 70 - 105 deg C
Low = less than 50 deg C
Switch pressed BAtXX.X Estimated present battery
voltage.
Switch pressed rES -X Seat belt buckle switch LH
status.1= Buckled
0 = Unbuckled
Switch pressed
(32 times) PA -XX through PA1-XX N/A
Switch pressed GAGE Return to beginning of self-diagno-
sis cycle.
Event
Odometer Display Description of Test/Data Notes:
METER/M&A diagnosis mode Description
SELF-DIAG RESULTS Displays combination meter self-diagnosis results. DATA MONITOR Displays combination meter input/output data in real time.
CAN DIAG SUPPORT MNTR The result of transmit/receive diagnosis of CAN communication can be read.
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WCS-14
< FUNCTION DIAGNOSIS >
DIAGNOSIS SYSTEM (METER)
X: Applicable
Display item [Unit]MAIN
SIGNALS SELECTION
FROM MENU Description
SPEED METER [km/h] or [mph] X X Displays the value of vehicle speed signal.
SPEED OUTPUT [km/h] or [mph] X XDisplays the value of vehicle speed signal, which is transmitted to
each unit with
CAN communication.
TACHO METER [rpm] XX Displays the value of engine speed signal, which is input from ECM.
FUEL METER [lit.] XXDisplays the value, which processes a resistance signal from fuel
gauge.
W TEMP METER [ °C] or [° F] X XDisplays the value of engine coolant temperature signal, which is in-
put from ECM.
ABS W/L [ON/OFF] X Displays [ON/OFF] condition of ABS warning lamp.
VDC/TCS IND [ON/OFF] X Displays [ON/OFF] condition of VDC OFF indicator lamp.
SLIP IND [ON/OFF] X Displays [ON/OFF] condition of SLIP indicator lamp.
BRAKE W/L [ON/OFF] X Displays [ON/OFF] condition of brake warning lamp.*
DOOR W/L [ON/OFF] X Displays [ON/OFF] condition of door warning lamp.
TRUNK W/L [ON/OFF] X Displays [ON/OFF] condition of glass hatch warning lamp.
HI-BEAM IND [ON/OFF] X Displays [ON/OFF] condition of high beam indicator.
TURN IND [ON/OFF] X Displays [ON/OFF] conditio n of turn indicator.
OIL W/L [ON/OFF] X Displays [ON/OFF] condition of oil pressure warning lamp.
C-ENG W/L [ON/OFF] X Displays [ON/OFF] condition of malfunction indicator lamp.
CRUISE IND [ON/OFF] X Displays [ON/OFF] condition of CRUISE indicator.
SET IND [ON/OFF] X Displays [ON/OFF] condition of SET indicator.
AT CHECK W/L [ON/OFF] X Displays [ON/OFF] condition of AT CHECK warning lamp.
FUEL W/L [ON/OFF] XX Displays [ON/OFF] condition of low-fuel warning lamp.
AIR PRES W/L [ON/OFF] X Displays [ON/OFF] condition of tire pressure warning lamp.
KEY G W/L [ON/OFF] X Displays [ON/OFF] condition of key green warning lamp.
KEY R W/L [ON/OFF] X Displays [ON/OFF] condition of key red warning lamp.
KEY KNOB W/L [ON/OFF] X Displays [ON/OFF] condition of key knob warning lamp.
M RANGE SW [ON/OFF] XX Displays [ON/OFF] condition of manual mode range switch.
NM RANGE SW [ON/OFF] XXDisplays [ON/OFF] condition of except for manual mode range
switch.
AT SFT UP SW [ON/OFF] XX Displays [ON/OFF] condition of A/T shift-up switch.
AT SFT DWN SW [ON/OFF] XX Displays [ON/OF F] condition of A/T shift-down switch.
DISTANCE [km] or [mile] XXDisplays the value, which is calculated by vehicle speed signal, fuel
gauge and fuel consumption from ECM.
BUZZER [ON/OFF] XX Displays [ON/ OFF] condition of buzzer.
BRAKE SW [ON/OFF] X Indicates [ON/OFF] condition of parking brake switch.
AT-M GEAR [1, 2, 3, 4, 5] XX Indicates [1, 2, 3, 4, 5] condition of A/T manual mode gear position.
P RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift P range indicator.
R RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift R range indicator.
N RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift N range indicator.
D RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift D range indicator.
4 RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift 4 range indicator.
3 RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift 3 range indicator.
2 RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift 2 range indicator.
1 RANGE IND [ON/OFF] XX Indicates [ON/OFF] condition of A/T shift 1range indicator.
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COMBINATION METERWCS-29
< ECU DIAGNOSIS >
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ECU DIAGNOSIS
COMBINATION METER
Reference ValueINFOID:0000000004871168
TERMINAL LAYOUT
PHYSICAL VALUES
WKIA5724E
Te r m i - nal Wire
color Item Condition
Reference value (V)
(Approx.)
Ignition
switch Operation or condition
3 Y/L Fuel level sensor signal — —Refer to
MWI-12, "
FUEL GAUGE : System
Description".
4 B/P Fuel level sensor ground ON —0
6 BR/W Generator ONGenerator voltage low
0
Generator voltage normal Battery voltage
10 L CAN-H —— —
11 P C A N - L —— —
13 P Air bag warning lamp in-
put ONAir bag warning lamp ON
4
Air bag warning lamp OFF 0
15 BR CK SUSP warning lamp
input —CK SUSP warning lamp
ON
0
CK SUSP warning lamp
OFF Battery voltage
20 B Ground —— 0
21 O/L Ignition switch ON or
START ON
— Battery voltage
23 W/L Washer fluid level switch ON Washer fluid level low
0
Washer fluid level normal Battery voltage
24 O/B Seat belt buckle switch
LH ONUnfastened (ON)
0
Fastened (OFF) Battery voltage
25 P/L Seat belt buckle switch
RH ONUnfastened (ON)
0
Fastened (OFF) Battery voltage
31 G Parking brake switch ON Parking brake applied
0
Parking brake released Battery voltage
32 P/B Brake fluid level switch ON Brake fluid level low
0
Brake fluid level normal Battery voltage
33 R/G Stop lamp switch —Brake pedal depressed
Battery voltage
Brake pedal released 0
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COMBINATION METERWCS-49
< ECU DIAGNOSIS >
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DTC IndexINFOID:0000000004871171
Function Specifications
Speedometer
Zero indication.
Tachometer
Fuel gauge
Engine coolant temperature gauge
Engine oil pressure gauge
Voltage gauge
A/T oil temperature gauge
Illumination control
Meter illumination Change to nighttime mode when communication is lost.
Segment LCD Odometer
Freeze current indication.
A/T position Display turns off.
Buzzer Buzzer turns off.
Warning lamp/indicator lamp ABS warning lamp
Lamp turns on when communication is lost.
Brake warning lamp
VDC OFF indicator lamp
SLIP indicator lamp
A/T CHECK warning lamp
Lamp turns off when communication is lost.
Oil pressure/coolant temperature
warning lamp
Light indicator
Malfunction indicator lamp
Master warning lamp
Air bag warning lamp
High beam indicator
Turn signal indicator lamp
CRUISE indicator lamp
Driver and passenger seat belt warn-
ing lamp
Lamp turns off when disconnected.
Charge warning lamp
Security indicator lamp
4WD indicator lamp
ATP indicator lamp
CK SUSP warning lamp
Low tire pressu
re warning lamp Lamp will flash every second for 1 minute and then stay on con-
tinuously thereafter.
CONSULT-III display
MalfunctionReference
page
CAN COMM CIRC
[U1000] Malfunction is detected in CAN communication.
CAUTION:
Even when there is no ma
lfunction on CAN communication system, malfunction may be
misinterpreted when battery has low voltag e (when maintaining 7 - 8 V for about 2 sec-
onds) or 10A fuse [No. 19, located in the fuse block (J/B)] is disconnected. MWI-28
VEHICLE SPEED
CIRC
[B2205]Malfunction is detected when an erroneous speed signal is input.
CAUTION:
Even when there is no malfunction on speed signal system, malfunction may be misin-
terpreted when battery has low voltage (whe
n maintaining 7 - 8 V for about 2 seconds). MWI-29
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2008 QX56

WW-58
< ECU DIAGNOSIS >
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
Te r m i n a lWire
color Signal name Signal
input/
output Measuring condition
Reference value(Approx.)
Igni-
tion
switch Operation or condition
1 B/Y Battery power supply Input OFF —Battery voltage
2 R Battery power supply Input OFF —Battery voltage
3 BR ECM relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
4 W/L ECM relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
6L Throttle control motor
relay Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
7 W/B ECM relay control Input — Ignition switch ON or START
0V
Ignition switch OFF or ACC Battery voltage
8 R/B Fuse 54 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
10 G Fuse 45 Output ONDaytime light system active
0V
Daytime light system inactive Battery voltage
11 Y/B A/C compressor Output ON or
START A/C switch ON or defrost A/C
switch
Battery voltage
A/C switch OFF or defrost A/C
switch 0V
12 L/W Ignition switch sup-
plied power Input —OFF or ACC
0V
ON or START Battery voltage
13 B/Y Fuel pump relay Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
14 Y/R Fuse 49 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
15 LG/B Fuse 50 (VDC) Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
15 GR Fuse 50 (ABS) Output — Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
16 G Fuse 51 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
17 W Fuse 55 Output —Ignition switch ON or START
Battery voltage
Ignition switch OFF or ACC 0V
19 W/R Starter motor Output START—Battery voltage
21 BR Ignition switch sup-
plied power
Input —OFF or ACC
0V
START Battery voltage
22 G Battery power supply Output OFF —Battery voltage
23 GR/W Door mirror defogger
output signal Output —When rear defogger switch is
ON
Battery voltage
When raker defogger switch is
OFF 0V
Revision: March 2010
2008 QX56