2008 INFINITI QX56 engine coolant

STR-6
< BASIC INSPECTION >
DIAGNOSIS AND REPAIR WORKFLOW
NOTE:
To ensure a complete and thorough diagnosis, the battery, starter motor and alternator test segments must be
done as a set from start to finish.
1.DIAGNOSIS WITH STARTING/CHARGING SYSTEM TESTER
Perform the starting system test with Starting/Charging System Tester (J-44373). For details and operating
instructions, refer to Technical Service Bulletin.
Te s t r e s u l t
CRANKING VOLTAGE NORMAL>>GO TO 2
CRANKING VOLTAGE LOW>>GO TO 5
CHARGE BATTERY>>Perform the slow battery charging procedure. (Initial rate of charge is 10A for 12
hours.) Perform battery test again. Refer to Technical Service Bulletin.
REPLACE BATTERY>>Before replacing battery, clean t he battery cable clamps and battery posts. Perform
battery test again. Refer to Technical Service Bulletin. If second test result is “REPLACE BAT-
TERY”, then do so. Perform battery test again to confirm repair.
2.CRANKING CHECK
Check that the starter motor operates properly.
Does the engine crank normally?
YES >> GO TO 3
NO >> GO TO 4
3.ENGINE START CHECK
Check that the engine starts.
Does the engine start?
YES >> Starter motor is OK. Inspection end.
NO >> Perform further diagnosis of engine mechanical or engine control system. Refer to EM and EC sections. Once resolved, perform battery test again.
4.STARTER MOTOR ACTIVATION
Check that the starter motor operates.
Does the starter motor turn?
YES >> Check ring gear and starter motor drive pinion. Once resolved, perform battery test again.
NO >> GO TO 7
5.COMPARISON BETWEEN ENGINE COOLANT AND CRANKING VOLTAGE
Compare the engine coolant temperature and verify the cranking voltage is within specification.
Minimum Specification of Cranking Voltage Referencing Coolant Temperature
Is the voltage less than the specified value?
YES >> GO TO 7
NO >> GO TO 6
6.STARTER OPERATION
Check the starter operation.
Does the starter motor turn smoothly?
YES >> Starter motor is OK. Inspection end.
NO >> GO TO 7
7.“B” TERMINAL CIRCUIT INSPECTION
Check “B” terminal circuit. Refer to STR-10, "
Diagnosis Procedure".
Is
“B” terminal circuit normal?
Engine coolant temperature [ °C ( °F)] Voltage [V]
− 30 to − 20 (−22 to − 4) 8.6
− 19 to −10 ( −2 to 14) 9.1
− 9 to 0 (16 to 32) 9.5
More than 1 (More than 34) 9.9
Revision: March 2010 2008 QX56

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

HEATER & COOLING UNIT ASSEMBLYVTL-17
< ON-VEHICLE REPAIR >
C
DE
F
G H
J
K L
M A
B
VTL
N
O P
1. Move the two front seats to the rear most position on the seat track.
2. Disconnect the battery negative terminal and battery positive terminal.
3. Discharge the refrigerant from the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
4. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
5. Disconnect the front heater hoses from the front heater core.
6. Disconnect the high/low pressure pipes from the front expansion valve.
7. Remove the instrument panel and console panel. Refer to IP-12, "
Removal and Installation".
8. Remove the steering column. Refer to ST-20, "
Removal and Installation".
9. Disconnect the instrument panel wire harness at t he RH and LH in-line connector brackets, and the fuse
block (J/B) electrical connectors. Refer to PG-9, "
Wiring Diagram — Battery Power Supply —".
10. Disconnect the steering member from each side of the vehicle body.
11. Remove the front heater and cooling unit assembly with it attached to the steering member, from the vehi- cle.
CAUTION:
Use care not to damage the seats and interior trim panels when removing the front heater and
cooling unit assembly with it at tached to the steering member.
12. Remove the front heater and cooling uni t assembly from the steering member.
Installation
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply com-
pressor oil to it when installing it.
• After charging the refrigerant, check for leaks.
NOTE:
• Fill the engine cooling system with the specified coolant mixture. Refer to CO-11, "
Changing Engine Cool-
ant".
• Recharge the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
REAR HEATER AND COOLING UNIT ASSEMBLY
Removal
1. Discharge the refrigerant from the A/C system. Refer to HA-20, "HFC-134a (R-134a) Service Procedure".
2. Drain the coolant from the engine cooling system. Refer to CO-11, "
Changing Engine Coolant".
3. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
4. Disconnect the rear heater core hoses from the rear heater core.
5. Disconnect the rear A/C pipes from the rear expansion valve.
6. Disconnect the following electrical connectors: • Rear blower motor
• Rear variable blower control
• Rear air mix door motor
7. Disconnect the ducts from the rear heater and cooling unit assembly.
8. Remove the rear heater and cooling unit assembly.
Installation
Installation is in the reverse order of removal.
CAUTION:
• Replace the O-ring of the low-pressure pipe and high-pressure pipe with a new one, and apply com- pressor oil to it when installing it.
• After charging the refrigerant, check for leaks.
NOTE:
• Fill the engine cooling system with the specified coolant mixture. Refer to CO-11, "
Changing Engine Cool-
ant".
• Recharge the A/C system. Refer to HA-20, "
HFC-134a (R-134a) Service Procedure".
Revision: March 2010 2008 QX56

VTL-20
< ON-VEHICLE REPAIR >
HEATER CORE
5. Remove the heater core.NOTE:
If the in-cabin microfilters are c ontaminated from coolant leaking
from the heater core, replace the in-cabin microfilters with new
ones before installing the new heater core.
Installation
Installation is in the reverse order of removal.
REAR HEATER CORE
Removal
1. Partially drain the engine cooling system. Refer to CO-11, "Changing Engine Coolant".
2. Remove the luggage side finisher lower RH. Refer to INT-19, "
Removal and Installation".
3. Disconnect the rear heater hoses from the heater core.
4. Remove the rear heater core bracket.
5. Remove the heater core.
Installation
Installation is in the reverse order of removal.
LJIA0134E
Revision: March 2010 2008 QX56

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.
Revision: March 2010 2008 QX56

WCS
COMBINATION METERWCS-49
< ECU DIAGNOSIS >
C
DE
F
G H
I
J
K L
M B A
O P
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
Revision: March 2010
2008 QX56

DIAGNOSIS SYSTEM (IPDM E/R)WW-13
< FUNCTION DIAGNOSIS >
C
DE
F
G H
I
J
K
M A
B
WW
N
O P
DIAGNOSIS SYSTEM (IPDM E/R)
Diagnosis DescriptionINFOID:0000000004874864
AUTO ACTIVE TEST
Description
In auto active test mode, the IPDM E/R sends a drive signal to the following systems to check their operation.
• Oil pressure low/coolant pressure high warning indicator
• Oil pressure gauge
• Rear window defogger
• Front wipers
• Tail, license and parking lamps
• Front fog lamps
• Headlamps (Hi, Lo)
• A/C compressor (magnetic clutch)
• Cooling fan
Operation Procedure
1. Close the hood and front door RH, and lift the wiper arms from the windshield (to prevent windshield dam-
age due to wiper operation).
NOTE:
When auto active test is performed with hood opened, sprinkle water on windshield before hand.
2. Turn ignition switch OFF.
3. Turn the ignition switch ON and, within 20 seconds, press the front door switch LH 10 times. Then turn the ignition switch OFF.
4. Turn the ignition switch ON within 10 seconds. Af ter that the horn sounds once and the auto active test
starts.
5. After a series of the following operations is repeated 3 times, auto active test is completed.
NOTE:
When auto active test mode has to be cancelled halfway through test, turn ignition switch OFF.
CAUTION:
• If auto active test mode cannot be actua ted, check door switch system. Refer to DLK-67, "
Descrip-
tion".
• Do not start the engine.
Inspection in Auto Active Test Mode
When auto active test mode is actuated, the following 7 steps are repeated 3 times.
Operation
sequence Inspection Location
Operation
1 Rear window defogger 10 seconds
2 Front wipers LO for 5 seconds → HI for 5 seconds
WKIA4655E
Revision: March 2010 2008 QX56

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
WW-55
< ECU DIAGNOSIS >
C
D E
F
G H
I
J
K
M A
B
WW
N
O P
IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE
ROOM)
Reference ValueINFOID:0000000004874899
VALUES ON THE DIAGNOSIS TOOL
Monitor Item ConditionValue/Status
MOTOR FAN REQ Engine idle speed Changes depending on engine
coolant temperature, air conditioner
operation status, vehicle speed,
etc.0 - 100 %
A/C COMP REQ A/C switch OFF
OFF
A/C switch ON ON
TA I L & C L R R E Q Lighting switch OFF
OFF
Lighting switch 1ST, 2ND, HI or AUTO (Light is illuminated) ON
HL LO REQ Lighting switch OFF
OFF
Lighting switch 2ND HI or AUTO (Light is illuminated) ON
HL HI REQ Lighting switch OFF
OFF
Lighting switch HI ON
FR FOG REQ Lighting switch 2ND or AUTO (Light
is illuminated) Front fog lamp switch OFF OFF
• Front fog lamp switch ON
• Daytime light activated (Canada
only) ON
HL WASHER REQ NOTE:
This item is displayed, but cannot be monitored.
OFF
FR WIP REQ Ignition switch ON Front wiper switch OFF
STOP
Front wiper switch INT 1LOW
Front wiper switch LO LOW
Front wiper switch HI HI
WIP AUTO STOP Ignition switch ON Front wiper stop position
STOP P
Any position other than front wiper
stop position ACT P
WIP PROT Ignition switch ON Front wiper operates normally OFF
Front wiper stops at fail-safe opera-
tion
BLOCK
ST RLY REQ Ignition switch OFF or ACC
OFF
Ignition switch START ON
IGN RLY Ignition switch OFF or ACC
OFF
Ignition switch ON ON
RR DEF REQ Rear defogger switch OFF
OFF
Rear defogger switch ON ON
OIL P SW Ignition switch OFF, ACC or engine running
OPEN
Ignition switch ON CLOSE
DTRL REQ Daytime light system requested OFF with CONSULT-III.
OFF
Daytime light system reques ted ON with CONSULT-III. ON
HOOD SW Hood closed.
OFF
Hood open. ON
Revision: March 2010 2008 QX56