2005 INFINITI QX4 check engine

CO-18Revision: October 2005
WATER PUMP
2005 QX56

After installation bleed the air from the cooling system. Refer to MA-14, "REFILLING ENGINE COOLANT"
.
INSPECTION AFTER INSTALLATION

Check for leaks of engine coolant. Refer to CO-10, "CHECKING COOLING SYSTEM FOR LEAKS" .

Start and warm up engine. Visually check for leaks of the engine coolant.

CO-20Revision: October 2005
THERMOSTAT AND WATER PIPING
2005 QX56
CAUTION:
Perform when the engine is cold.
2. Remove the air duct and resonator assembly. Refer to EM-14, "
REMOVAL" .
3. Remove the engine room cover using power tool.
4. Disconnect the heater hose (heater core side).
5. Remove the heater hose bracket.
6. Disconnect the water cut valve connector.
7. Remove the water cut valve.
INSPECTION AFTER REMOVAL

Place a thread so that it is caught in the valve of the thermostat.
Immerse fully in a container filled with water. Heat while stirring.

The valve opening temperature is the temperature at which the
valve opens and falls from the thread.

Continue heating. Check the full-open lift amount.

After checking the full-open lift amount, lower the water temper-
ature and check the valve closing temperature.
Standard values:
INSTALLATION
Installation is in the reverse order of removal.
Installation of Thermostat

Install the thermostat with the whole circumference of each
flange part fit securely inside the rubber ring as shown.

Install the thermostat with the jiggle valve facing upwards.
Installation of Water Outlet Pipe and Heater Pipe
First apply a neutral detergent to the O-rings, then quickly insert the insertion parts of the water outlet pipe and
heater pipe into the installation holes.
INSPECTION AFTER INSTALLATION

Check for leaks of the engine coolant. Refer to CO-10, "CHECKING COOLING SYSTEM FOR LEAKS" .

Start and warm up the engine. Visually check for leaks of the engine coolant.
SL C2 52 B
Thermostat
Valve opening temperature 80 - 84°C (176 - 183° F)
Full-open lift amount More than 10 mm/ 95°C (0.39 in/ 203°F)
Valve closing temperature 77°C (171°F) or higher
KBIA2502E

DI-1
DRIVER INFORMATION SYSTEM
K ELECTRICAL
CONTENTS
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SECTION DI
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Revision: October 20052005 QX56 PRECAUTION ............................................................ 3
Precautions for Supplemental Restraint System
(SRS) “AIR BAG” and “SEAT BELT PRE-TEN-
SIONER” .................................................................. 3
Wiring Diagrams and Trouble Diagnosis .................. 3
PREPARATION ........................................................... 4
Commercial Service Tool ......................................... 4
COMBINATION METERS ........................................... 5
System Description .................................................. 5
UNIFIED METER CONTROL UNIT ...................... 5
POWER SUPPLY AND GROUND CIRCUIT ........ 6
WATER TEMPERATURE GAUGE ........................ 6
ENGINE OIL PRESSURE GAUGE ....................... 6
A/T OIL TEMPERATURE GAUGE ........................ 6
VOLTAGE GAUGE ................................................ 6
TACHOMETER ..................................................... 6
FUEL GAUGE ....................................................... 6
SPEEDOMETER ................................................... 6
CAN COMMUNICATION SYSTEM DESCRIP-
TION ...................................................................... 6
Component Parts and Harness Connector Location ..... 7
Combination Meter ................................................... 8
CHECK .................................................................. 8
Circuit Diagram ........................................................ 9
Wiring Diagram — METER — ................................ 10
Terminals and Reference Value for Combination
Meter ...................................................................... 12
Meter/Gauge Operation and Odo/Trip Meter ......... 13
SELF-DIAGNOSIS FUNCTION .......................... 13
HOW TO INITIATE COMBINATION METER
SELF- DIAGNOSIS MODE ................................. 13
COMBINATION METER SELF-DIAGNOSIS
MODE FUNCTIONS ........................................... 13
How to Proceed With Trouble Diagnosis ................ 17
Diagnosis Flow ....................................................... 17
Power Supply and Ground Circuit Inspection ........ 18
Symptom Chart ...................................................... 19
Vehicle Speed Signal Inspection ............................ 19
Engine Oil Pressure Signal Inspection ................... 19
Water Temperature Signal Inspection .................... 21Engine Speed Signal Inspection ............................. 21
Fuel Level Sensor Unit Inspection .......................... 22
FUEL LEVEL SENSOR UNIT ............................. 22
LOW-FUEL WARNING LAMP ............................. 22
Fuel Gauge Fluctuates, Indicates Wrong Value, or
Varies ...................................................................... 24
Fuel Gauge Does Not Move to Full-position ........... 24
Electrical Components Inspection .......................... 25
FUEL LEVEL SENSOR UNIT CHECK ................ 25
Removal and Installation of Combination Meter ..... 25
COMPASS AND THERMOMETER ........................... 26
System Description ................................................. 26
OUTSIDE TEMPERATURE DISPLAY ................. 26
DIRECTION DISPLAY ......................................... 26
Wiring Diagram — COMPAS — ............................. 27
Trouble Diagnoses ................................................. 28
PRELIMINARY CHECK FOR THERMOMETER ... 28
INSPECTION/COMPASS AND THERMOME-
TER ..................................................................... 28
Calibration Procedure for Compass ....................... 29
CORRECTION FUNCTIONS OF COMPASS ...... 29
INITIAL CORRECTION PROCEDURE FOR
COMPASS ........................................................... 29
WARNING LAMPS .................................................... 30
Schematic ............................................................... 30
Wiring Diagram — WARN — .................................. 31
Oil Pressure Warning Lamp Stays Off (Ignition
Switch ON) ............................................................. 37
Oil Pressure Warning Lamp Does Not Turn Off (Oil
Pressure Is Normal) ................................................ 39
A/T INDICATOR ........................................................ 40
Wiring Diagram — AT/IND — ................................. 40
A/T Indicator Does Not Illuminate ........................... 41
WARNING CHIME ..................................................... 42
Component Parts and Harness Connector Location ... 42
System Description ................................................. 42
FUNCTION .......................................................... 42
IGNITION KEY WARNING CHIME ..................... 43
LIGHT WARNING CHIME ................................... 43
SEAT BELT WARNING CHIME ........................... 43

COMBINATION METERS
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Meter/Gauge Operation and Odo/Trip MeterEKS00BC0
SELF-DIAGNOSIS FUNCTION
The following items can be checked during Combination Meter Self-Diagnosis Mode.

Gauge sweep and present gauge values.

Illuminates all odometer, fuel, and engine temperature segments.

Illuminates all micro controlled lamps/LED's regardless of switch configuration.

Displays estimated present battery voltage.

Displays seat belt buckle switch LH status.
HOW TO INITIATE COMBINATION METER SELF- DIAGNOSIS MODE
NOTE:
Once entered, Combination Meter Self-Diagnosis Mode will function with the ignition switch in ON or START.
Combination Meter Self-Diagnosis Mode will exit upon turning the ignition switch to OFF or ACC.
To initiate Combination Meter Self-Diagnosis Mode, refer to the following procedure.
1. Turn the ignition switch ON, while holding the odometer/trip meter switch for 5 - 8 seconds.
NOTE:
If the diagnosis function is activated the odometer/trip meter will display tESt.
COMBINATION METER SELF-DIAGNOSIS MODE FUNCTIONS
To interpret Combination Meter Self-Diagnosis Mode functions, refer to the following table.
Event Odometer Display Description of Test/Data Notes:
Odometer/trip meter A/B
switch held from 5 to 8
seconds (or until
released)tESt Initiating self-diagnosis mode
Odometer/trip meter A/B
switch engaged and
released = next test
requestedrXXXX, FAILReturn to normal opera-
tion of all lamps/LEDs and
displays hex ROM rev. If
a ROM checksum fault
exists, display alternates
between "r XXXX" and
"FAIL".
Next test requested nrXXXXDisplays hex ROM rev as
stored in NVM.
Next test requested GAGEPerforms sweep of all
gauges, then displays
present gauge values.
Performs checksum tests
on ROM and EE.Gauges sweep within 10 sec-
onds
Next test requested (All segments illuminated)Lights all odometer/trip
meter, fuel, and engine
temperature display seg-
ments.Initiating self-diagnosis mode
complete
Next test requested bulbIlluminates all micro-con-
trolled lamps/LEDs
regardless of SW configu-
ration.
Next test requested EE XX, FAILHex EE level. If EE
checksum fault exists,
display alternates
between "EE XX" and
"FAIL".
Next test requested dtXXXXHex coding of final manu-
facturing test date.

COMBINATION METERS
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Symptom ChartEKS00BC4
Vehicle Speed Signal InspectionEKS00BC5
1. CHECK ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT) SELF-DIAGNOSIS
Refer to BRC-29, "
SELF-DIAGNOSIS" .
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "Combination Meter" .
NG >> Perform the "Diagnostic Procedure" for displayed DTC. Refer to BRC-11, "
TROUBLE DIAGNO-
SIS" .
Engine Oil Pressure Signal Inspection EKS00BC6
1. CHECK OIL PRESSURE SENSOR SIGNAL
1. Turn ignition switch ON.
2. Check voltage between combination meter harness connector
M24 terminal 20 (Y) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
Trouble phenomenon Possible cause
Improper tachometer indication. Refer to DI-21, "
Engine Speed Signal Inspection" .
Improper water temperature gauge indication. Refer to DI-21, "
Water Temperature Signal Inspection" .
Improper speedometer or odometer. Refer to DI-19, "
Vehicle Speed Signal Inspection" .
Improper fuel gauge indication.
Refer to DI-22, "
Fuel Level Sensor Unit Inspection" .
Fuel warning lamp indication is irregular.
Improper A/T oil temperature gauge indicationRefer to AT-126, "
DTC P1710 A/T FLUID TEMPERATURE SEN-
SOR CIRCUIT" .
Improper voltage gauge indication
Replace combination meter. Refer to IP-13, "
Combination Meter"
.
More than one gauge does not give proper indication.
Improper A/T position indication. Refer to DI-40, "
A/T INDICATOR" .
Illumination control does not operate properly. Refer to LT-152, "
ILLUMINATION" .
Te r m i n a l s
Condition Voltage (V) (+)
(–)
ConnectorTe r m i n a l
(Wire color)
M24 20 (Y) GroundWhen ignition switch is in ON
position. (Engine stopped)Ye s
Engine running. (Idle speed) Yes
WKIA1833E

COMBINATION METERS
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5. CHECK OIL PRESSURE SENSOR SIGNAL CIRCUIT
1. Check continuity between combination meter harness connector M24 terminal 20 (Y) and oil pressure
sensor harness connector F4 terminal 2 (Y).
2. Check continuity between combination meter harness connector
M24 terminal 20 (Y) and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.
6. CHECK OIL PRESSURE SENSOR GROUND CIRCUIT
Check continuity between combination meter harness connector
M24 terminal 16 (B/P) and ground.
OK or NG
OK >> Replace oil pressure sensor.
NG >> Repair harness or connector.
Water Temperature Signal Inspection EKS00BC7
1. CHECK ECM SELF-DIAGNOSIS
Perform ECM self-diagnosis. Refer to EC-130, "
SELF-DIAG RESULTS MODE" .
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "Combination Meter" .
NG >> Perform "Diagnostic procedure" for displayed DTC. Refer to EC-95, "
TROUBLE DIAGNOSIS" .
Engine Speed Signal Inspection EKS00BC8
1. CHECK ECM SELF-DIAGNOSIS
Perform ECM self-diagnosis. Refer to EC-130, "
SELF-DIAG RESULTS MODE" .
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "Combination Meter" .
NG >> Perform "Diagnostic procedure" for displayed DTC. Refer to EC-95, "
TROUBLE DIAGNOSIS" . Continuity should exist.
Continuity should not exist.
WKIA1836E
Continuity should not exist.
WKIA2685E

DI-28
COMPASS AND THERMOMETER
Revision: October 20052005 QX56
Trouble DiagnosesEKS00BCG
PRELIMINARY CHECK FOR THERMOMETER
1. COOL DOWN CHECK
1. Turn the ignition switch to the ON position.
2. Cool down the ambient sensor 2 with water or ice.
Does the indicated temperature drop?
YES >> GO TO 2.
NO >> The system is malfunctioning. Refer to DI-28, "
INSPECTION/COMPASS AND THERMOMETER"
.
2. WARM UP CHECK
1. Leave the vehicle for 10 minutes.
2. With the ignition switch in the ON position, disconnect and reconnect the ambient sensor 2 connector.
Does the indicated temperature rise?
YES >> The system is OK.
NO >> The system is malfunctioning. Refer to DI-28, "
INSPECTION/COMPASS AND THERMOMETER"
.
NOTE:
The indicated temperature on the thermometer is not readily affected by engine heat. It changes only when
one of the following conditions is present.

The temperature detected by the ambient sensor is lower than the indicated temperature on the thermom-
eter.

The vehicle speed is greater than 20 km/h (13 MPH).
(This is to prevent the indicated temperature from being affected by engine heat during low-speed driv-
ing.)

The ignition switch has been turned to the OFF position for more than 2 hours. (The engine is cold.)
INSPECTION/COMPASS AND THERMOMETER
Symptom Possible causes Repair order
No display at all 1. 10A fuse
2. Ground circuit
3. Compass and thermometer1. Check 10A fuse [No. 12, located in fuse block (J/B)].
Turn the ignition switch ON and verify that battery positive volt-
age is at terminal 2 of compass and thermometer.
2. Check ground circuit for compass and thermometer.
3. Replace compass and thermometer.
Forward direction indi-
cation slips off the mark
or incorrect.1. In manual correction mode (Bar and
display vanish)
2. Zone variation change is not done1. Drive the vehicle and turn at an angle of 90°.
2. Perform the zone variation change.
Compass reading
remains unchanged.1. Vehicle speed signal is not entered
2. Compass and thermometer1. Check harness for open or short between combination meter
terminal 29 and compass and thermometer terminal 8.
2. Replace compass and thermometer.
Displays wrong tem-
perature when ambient
temperature is between
−40°C (−40°F) and
55°C (130°F). (See
NOTE above.)1. Check operation
2. Ambient sensor circuit
3. Vehicle speed signal is not entered
4. Ambient sensor 2
5. Compass and thermometer1. Perform preliminary check shown above.
2. Check harness for open or short between ambient sensor 2 and
compass and thermometer.
3. Check harness for open or short between combination meter
terminal 29 and compass and thermometer terminal 8.
4. Replace ambient sensor 2.
5. Replace compass and thermometer.
Displays SC or OC. 1. Ambient sensor circuit
2. Ambient sensor 2
3. Compass and thermometer1. Check harness for open or short between ambient sensor 2 and
compass and thermometer.
2. Replace ambient sensor 2.
3. Replace compass and thermometer.

WARNING LAMPS
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Oil Pressure Warning Lamp Stays Off (Ignition Switch ON)EKS00BCK
1. CHECK OIL PRESSURE SENSOR SIGNAL
1. Turn ignition switch ON.
2. Check voltage between combination meter harness connector
M24 terminal 20 (Y) and ground.
OK or NG
OK >> GO TO 2.
NG >> GO TO 3.
2. CHECK OIL PRESSURE SENSOR GROUND CIRCUIT
1. Turn ignition switch OFF.
2. Disconnect combination meter connector M24 and oil pressure
sensor connector F4.
3. Check continuity between combination meter harness connector
M24 terminal 16 (B/P) and oil pressure sensor harness connec-
tor F4 terminal 3 (B/P).
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "Combi-
nation Meter" .
NG >> Repair harness or connector.
3. CHECK OIL PRESSURE SENSOR REFERENCE VOLTAGE
1. Turn ignition switch OFF.
2. Disconnect oil pressure sensor connector F4.
3. Turn ignition switch ON.
4. Check voltage between combination meter harness connector
M24 terminal 22 (GR/L) and ground.
OK or NG
OK >> GO TO 4.
NG >> Replace the combination meter. Refer to IP-13, "
Combi-
nation Meter" .
Te r m i n a l s
Condition Voltage (V) (+)
(–)
ConnectorTe r m i n a l
(Wire color)
M24 20 (Y) GroundWhen ignition switch is in ON
position. (Engine stopped)Ye s
Engine running. (Idle speed) Yes
WKIA1833E
Continuity should exist.
WKIA1837E
Voltage : Approx. 5V
WKIA1834E