2006 INFINITI QX56 air condition

CO-16Revision: November 2009
RADIATOR
2006 QX56
10. Lift up and remove the radiator.CAUTION:
Do not damage or scratch air conditioner condenser and
radiator core when removing.
INSTALLATION
Installation is in the reverse order of removal.
INSPECTION AFTER INSTALLATION

Check for leaks of 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 and A/T fluid.
Checking RadiatorEBS00REC
Check radiator for mud or clogging. If necessary, clean radiator as follows.
CAUTION:

Be careful not to bend or damage the radiator fins.

When radiator is cleaned without removal, remove all surrounding parts such as cooling fan, radi-
ator shroud and horns. Then tape the harness and electrical connectors to prevent water from
entering.
1. Apply water by hose to the back side of the radiator core vertically downward.
2. Apply water again to all radiator core surfaces.
3. Stop washing when dirt and debris no longer flow out from the radiator.
4. Blow air into the back side of radiator core vertically downward.

Use compressed air lower than 490 kPa (5 kg/cm2 , 71 psi) and keep distance more than 30 cm (11.8
in).
5. Blow air again into all the radiator core surfaces until no water sprays out.
PBIC1536E

ENGINE COOLING FANCO-17
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Revision: November 2009 2006 QX56
ENGINE COOLING FANPFP:21140
Removal and Installation (Crankshaft Driven Type)EBS00RED
REMOVAL
1. Remove the air duct and resonator assembly. Refer to EM-15, "Removal and Installation" .
2. Remove the engine front undercover using power tool.
3. Remove the lower radiator shroud. Refer to CO-14, "
Removal and Installation" .
4. Remove the drive belt. Refer to EM-13, "
Removal and Installation" .
5. Remove the cooling fan.
INSPECTION AFTER REMOVAL
Fan Coupling
Inspect fan coupling for oil leakage and bimetal conditions.
Fan Bracket

Visually check that there is no significant looseness in the fan
bracket shaft, and that it turns smoothly by hand.

If there are any unusual concerns, replace the cooling fan pulley.
INSTALLATION
Installation is in the reverse order of removal.

Install cooling fan with its front mark “F” facing front of engine. Refer to CO-17, "Removal and Installation
(Crankshaft Driven Type)" .
INSPECTION AFTER INSTALLATION

Check for leaks of the engine coolant. Refer to CO-10, "CHECKING COOLING SYSTEM FOR LEAKS" .
1. Cooling fan2. Fan coupling3. Fan bracket
4. Cooling fan pulley
WBIA0632E
SLC072
WBIA0418E

COMBINATION METERSDI-19
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Revision: November 2009 2006 QX56
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 "Diagnostic Procedure" for displayed DTC. Refer to BRC-11, "
TROUBLE DIAGNOSIS" .
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 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 and oil pressure sensor harness connector F4
terminal 3.
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "COM-
BINATION METER" .
NG >> Repair harness or connector.
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 indication Refer to
AT-127, "
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-41, "
A/T INDICATOR" .
Illumination control does not operate properly. Refer to LT-157, "
ILLUMINATION" .
Terminals
Condition Voltage (V)
(+)
(– )
Connector Terminal
M24 20 Ground When ignition switch is in ON
position. (Engine stopped)
Ye s
Engine running. (Idle speed) Yes
WKIA1833E
Continuity should exist.
WKIA1837E

COMBINATION METERSDI-23
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4. CHECK HARNESS FOR OPEN OR SHORT CIRCUIT
1. Turn the ignition switch OFF.
2. Disconnect combination meter connector M24.
3. Check continuity between combination meter harness connector M24 (B) terminal 15 and fuel level sensor unit and fuel pump
harness connector C5 (A) terminal 2.
4. Check continuity between fuel level sensor unit and fuel pump harness connector C5 (A) terminal 2 and ground.
OK or NG
OK >> GO TO 5.
NG >> Repair harness or connector.
5. CHECK FUEL LEVEL SENSOR CIRCUIT
1. Check continuity between combination meter harness connector M24 (B) terminal 16 and fuel level sensor unit and fuel pump
harness connector C5 (A) terminal 5.
2. Check continuity between fuel level sensor unit and fuel pump harness connector C5 (A) terminal 5 and ground.
OK or NG
OK >> GO TO 6.
NG >> Repair harness or connector.
6. CHECK FUEL LEVEL SENSOR UNIT
Check the fuel level sensor unit. Refer to DI-25, "
FUEL LEVEL SENSOR UNIT CHECK" .
OK or NG
OK >> GO TO 7.
NG >> Replace the fuel level sensor unit. Refer to IP-13, "
COMBINATION METER" .
7. CHECK INSTALLATION CONDITION
Check fuel level sensor unit installation, and determine whether the float arm interferes or binds with any of the
internal components in the fuel tank.
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "COMBINATION METER" .
NG >> Install the fuel level sensor unit properly. Continuity should exist.
Continuity should not exist.
WKIA4617E
Continuity should exist.
Continuity should not exist.
WKIA4618E

DI-38
WARNING LAMPS
Revision: November 20092006 QX56
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 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 and oil pressure sensor harness connector F4
terminal 3.
OK or NG
OK >> Replace the combination meter. Refer to IP-13, "COM-
BINATION 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 and ground.
OK or NG
OK >> GO TO 4.
NG >> Replace the combination meter. Refer to IP-13, "
COM-
BINATION METER" .
Terminals
Condition Voltage (V)
(+)
(– )
Connector Terminal
M24 20 Ground When ignition switch is in ON
position. (Engine stopped)
Ye s
Engine running. (Idle speed) Yes
WKIA1833E
Continuity should exist.
WKIA1837E
Voltage : Approx. 5V
WKIA1834E

WARNING CHIMEDI-49
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Terminals and Reference Value for Combination MeterEKS00BCT
How to Proceed With Trouble DiagnosisEKS00BCU
1. Confirm the symptom or customer complaint.
2. Understand operation description and function description. Refer to DI-44, "
System Description" .
3. Perform the preliminary check. Refer to DI-50, "
Preliminary Check" .
4. Check symptom and repair or replace the cause of malfunction.
5. Does the warning chime operate properly? If so, go to 6. If not, go to 3.
6. Inspection End.
35 O/B Combination switch output 2
ON

Light switch and wiper switch
OFF

Wiper dial position 4
36 R/W Combination switch output 1
37 B/R Key switch signal
OFFKey is removed
0
Key is inserted Battery voltage
38 W/L Ignition switch ON or START ON —Battery voltage
39 L CAN-H —— —
40 P CAN-L —— —
47 SB Front door switch LH signal OFF ON (open)
0
OFF (closed) 5
67 B Ground OFF— 0
70 W/B Battery power supply OFF— Battery voltage
Terminal
No. Wire
color Item Condition
Reference value (V)
(Approx.)
Ignition
switch Measurement method
SKIA5292E
Terminal
No. Wire
color Item Condition
Reference value (V)
(Approx.)
Ignition
switch Measurement method
11 L C A N - H —— —
12 P CAN-L —— —
17 B Ground OFF— 0
24 O/L Ignition switch ON or START ON —Battery voltage
27 O/B Seat belt buckle pre-ten-
sioner assembly (seat belt
buckle switch) LH
ONUnfastened (ON)
0
Fastened (OFF) Battery voltage

REAR SONAR SYSTEMDI-65
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Terminals And Reference Value For Sonar Control UnitEKS00BD5
How to Proceed With Trouble DiagnosisEKS00BD6
1. Confirm the symptom or customer complaint.
2. Understand operation description and function description. Refer to DI-61, "
System Description" .
3. Perform pre-diagnosis inspection. Refer to DI-66, "
Pre-diagnosis Inspection" .
4. Perform self-diagnosis. Refer to DI-66, "
Self-diagnosis Function" .
5. Perform the preliminary check. Refer to DI-68, "
Preliminary Check" .
6. Check symptom and repair or replace the cause of malfunction. Refer to DI-69, "
Symptom Chart" .
7. Does the rear sonar system operate properly? If so, go to 8. If not, go to 3.
8. Clear fault codes. Refer to DI-67, "
IDLING OR CLEARING FAULT CODES MODE" .
9. Inspection End.
TERMINAL (COLOR) ITEM CONDITION
Reference value (V)
(Approx.)
IGNITION
SWITCH OPERATION
3 (R) Sonar buzzer return ON —0 - 12 (variable)
4 (BR/Y) Rear sonar system
OFF indicator output ONRear sonar system OFF
switch ON
0
OFF 12
5 (G/W) Reverse signal ONTransmission gear
selector lever
R position
12
Transmission gear
selector lever Not R position
0
6 (B) Sonar control unit
ground ——
0
7 (L) Sonar buzzer drive signal ON
— 12
8 (G/R) Sonar control unit
power
ON
— 12
9 (GR) Rear sonar sensor
signal - RH outer ON

Rear sonar system OFF switch ON

Transmission gear selector lever in R
position

No obstacles 12
10 (P) Rear sonar sensor
signal - LH outer ON

Rear sonar system OFF switch ON

Transmission gear selector lever in R
position

No obstacles 12
11 ( O ) Rear sonar sensor
signal - LH inner ON

Rear sonar system OFF switch ON

Transmission gear selector lever in R
position

Distance obstacles 12
12 (LG) Rear sonar sensor
signal - RH inner ON

Rear sonar system OFF switch ON

Transmission gear selector lever in R
position

Distance obstacles 12
13 (LG) Rear sonar system
OFF switch signal ONRear sonar system OFF
switch ON
0
OFF 12
15 (Y) Rear sonar sensor
ground ON
— 0
16 (LG/B) Rear sonar sensor
power ON Ignition switch ON
12

REAR SONAR SYSTEMDI-69
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Revision: November 2009 2006 QX56
Symptom Chart EKS00BDA
SymptomRepair order
When the rear sonar system OFF switch is OFF, the indicator
lamp does not light and the buzzer does not sound. 1. Check rear sonar system OFF switch for malfunction. Refer to
DI-70, "
REAR SONAR SYSTEM OFF SWITCH" .
2. Check rear sonar system OFF switch ground circuit.
3. Check harness and connections between rear sonar system OFF switch and sonar control unit.
4. Replace sonar control unit. Refer to DI-70, "
SONAR CON-
TROL UNIT" .
When the rear sonar system OFF switch is OFF, the indicator
lamp does not light but buzzer sounds. 1. Check rear sonar system OFF indicator for malfunction. Refer
to DI-70, "
REAR SONAR SYSTEM OFF INDICATOR" .
2. Check harness and connections between rear sonar system OFF indicator and sonar control unit.
3. Replace sonar control unit. Refer to DI-70, "
SONAR CON-
TROL UNIT" .
When the rear sonar system OFF switch is OFF, the sonar
buzzer does not sound but indicator lamp illuminates. 1. Check sonar buzzer. Refer to
DI-70, "
SONAR BUZZER" .
2. Check harness and connections between sonar buzzer and sonar control unit.
3. Replace sonar control unit. Refer to: DI-70, "
SONAR CON-
TROL UNIT" .
When rear sonar system OFF switch is ON, the rear sonar sys-
tem OFF indicator lamp lights up and the sonar buzzer sounds
intermittently (for about 4 seconds). 1. Check harness between rear sonar sensors and sonar control
unit for an open condition.
2. Check rear sonar sensors for malfunction.
3. Replace sonar control unit. Refer to DI-70, "
SONAR CON-
TROL UNIT" .
The rear sonar system operates with the rear sonar system OFF
switch OFF. 1. Check rear sonar system OFF switch for malfunction. Refer to
DI-70, "
REAR SONAR SYSTEM OFF SWITCH" .
2. Check rear sonar system OFF switch ground circuit.
3. Check harness and connections between rear sonar system OFF switch and sonar control unit.
4. Replace sonar control unit. Refer to DI-70, "
SONAR CON-
TROL UNIT" .
When the transmission gear selector lever is in the R position
and the rear sonar system OFF switch is OFF, the sonar system
does not operate. 1. Check for PNP switch failure. Refer to
AT-86, "
SELF-DIAG-
NOSTIC RESULT MODE" .
2. Check harness and connections between sonar control unit and PNP/reverse lamp circuits.
3. Replace sonar control unit. Refer to DI-70, "
SONAR CON-
TROL UNIT" .
When the rear sonar system OFF switch is OFF, the indicator
lamp lights up and buzzer sounds although there is no obstacle
within the detection range. 1. Check for adhesion of snow, mud, or other foreign objects to
rear sonar sensors; dew condensation; etc. Refer to DI-66,
"Pre-diagnosis Inspection" .
2. Check that the rear sonar sensor is properly aligned (bumper is not misaligned, no deformation in sensor mounting area
3. Check harness and connections between rear sonar sensors and sonar control unit.
4. Check rear sonar sensors for malfunction.
5. Replace sonar control unit. Refer to DI-70, "
SONAR CON-
TROL UNIT" .
The rear sonar sensors do not operate according to the distance
between each sensor and the obstacle. (There is a large error in
the obstacle detection distance. 1. Check rear sonar sensors for malfunction.
2. Replace sonar control unit. Refer to
DI-70, "
SONAR CON-
TROL UNIT" .
3. Check for adhesion of snow, mud, or other foreign objects to rear sonar sensors; dew condensation; etc. Refer to DI-66,
"Pre-diagnosis Inspection" .
4. Check that the rear sonar sensor is properly aligned (bumper is not misaligned, no deformation in sensor mounting area