2004 INFINITI QX56 low oil pressure

ATC-176
REFRIGERANT LINES
Revision: August 20072004 QX56
2. Remove the defroster mode door arm.
3. Separate the heater core and cooling unit case.
4. Remove the evaporator.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:
Replace the O-rings on the low-pressure flexible hose and the high-pressure pipe with new ones.
Apply compressor oil to the O-rings before installing them.
Removal and Installation for Rear EvaporatorEJS002DS
Rear Heater and Cooling Unit Assembly
LJIA0135E
1. Front cover 2. Evaporator and heater core case 3. Evaporator
4. Side cover 5. Heater core 6. Rear blower motor
7. Blower motor case 8. Rear blower motor resistor

ATC-178
REFRIGERANT LINES
Revision: August 20072004 QX56
CAUTION:
Cap or wrap the A/C refrigerant pipe ends with a suitable material such as vinyl tape to avoid the
entry of contaminants.
4. Remove the expansion valve.
INSTALLATION
Installation is in the reverse order of removal.
CAUTION:

Replace the O-rings on the A/C refrigerant pipes with new ones, then apply compressor oil to them
when installing them.

After charging refrigerant, check for leaks.
Checking for Refrigerant LeaksEJS002DV
Perform a visual inspection of all refrigeration parts, fittings, hoses and components for signs of A/C lubricant
leakage, damage, and corrosion. Any A/C lubricant leakage may indicate an area of refrigerant leakage. Allow
extra inspection time in these areas when using either an electronic refrigerant leak detector (J-41995) or fluo-
rescent dye leak detector (J-42220).
If any dye is observed using a fluorescent dye leak detector (J-42220), confirm the leak using a electronic
refrigerant leak detector (J-41995). It is possible that the dye is from a prior leak that was repaired and not
properly cleaned.
When searching for leaks, do not stop when one leak is found but continue to check for additional leaks at all
system components and connections.
When searching for refrigerant leaks using an electronic refrigerant leak detector (J-41995), move the probe
along the suspected leak area at 25 - 50 mm (1 - 2 in) per second and no further than 6 mm (1/4 in) from the
component.
CAUTION:
Moving the electronic refrigerant leak detector probe slower and closer to the suspected leak area will
improve the chances of finding a leak.
Checking System for Leaks Using the Fluorescent Dye Leak DetectorEJS002DW
1. Check the A/C system for leaks using the fluorescent dye leak detector and safety goggles (J-42220) in a
low sunlight area (area without windows preferable). Illuminate all components, fittings and lines. The dye
will appear as a bright green/yellow area at the point of leakage. Fluorescent dye observed at the evapo-
rator drain opening indicates an evaporator core assembly leak (tubes, core or expansion valve).
2. If the suspected area is difficult to see, use an adjustable mirror or wipe the area with a clean shop rag or
cloth, then inspect the shop rag or cloth with the fluorescent dye leak detector (J-42220) for dye residue.
3. After the leak is repaired, remove any residual dye using refrigerant dye cleaner (J-43872) to prevent
future misdiagnosis.
4. Perform a system performance check and then verify the leak repair using a electronic refrigerant leak
detector (J-41995).
NOTE:

Other gases in the work area or substances on the A/C components, for example, anti-freeze, wind-
shield washer fluid, solvents and lubricants, may falsely trigger the leak detector. Make sure the sur-
faces to be checked are clean.

Clean with a dry cloth or blow off with shop air.

Do not allow the sensor tip of the electronic refrigerant leak detector (J-41995) to contact with any sub-
stance. This can also cause false readings and may damage the detector.
Dye InjectionEJS002DX
NOTE:
This procedure is only necessary when recharging the system or when the compressor has seized and must
be replaced.
1. Check the A/C system static (at rest) pressure. Pressure must be at least 345 kPa (3.52 kg/cm
2 , 50 psi). Expansion valve bolts : 4 N·m (0.41 kg-m, 35 in-lb)
A/C refrigerant pipe to expansion valve bolt : Refer to ATC-164, "
Compo-
nents" .

REFRIGERANT LINES
ATC-179
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Revision: August 20072004 QX56
2. Pour one bottle 7.4 cc (1/4 ounce) of the HFC-134a (R-134a) fluorescent leak detection dye (J-41447) into
the HFC-134a (R-134a) dye injector (J-41459).
CAUTION:
If repairing the A/C system or replacing a component, pour the HFC-134a (R-134a) fluorescent leak
detection dye (J-41447) directly into the open system connection and proceed with the service
procedures.
3. Connect the refrigerant dye injector (J-41459) to the low-pressure service valve.
4. Start the engine and switch the A/C system ON.
5. When the A/C system is operating (compressor running), inject one bottle 7.4 cc (1/4 ounce) of HFC-134a
(R-134a) fluorescent leak detection dye (J-41447) through the low-pressure service valve using HFC-
134a (R-134a) dye injector (J-41459). Refer to the manufacturer's operating instructions.
6. With the engine still running, disconnect the HFC-134a (R-134a) dye injector (J-41459) from the low-pres-
sure service valve.
7. Operate the A/C system for a minimum of 20 minutes to mix the HFC-134a (R-134a) fluorescent leak
detection dye (J-41447) with the A/C system oil. Depending on the leak size, operating conditions and
location of the leak, it may take from minutes to days for the HFC-134a (R-134a) fluorescent leak detec-
tion dye to penetrate an A/C system leak and become visible.
Electronic Refrigerant Leak DetectorEJS002DY
PRECAUTIONS FOR HANDLING LEAK DETECTOR
NOTE:
When performing a refrigerant leak check, use a electronic refrigerant leak detector (J-41995) or equivalent.
Ensure that the electronic refrigerant leak detector (J-41995) is calibrated and set properly according to the
manufacturer's operating instructions.
The electronic refrigerant leak detector (J-41995) is a delicate
device. To use the leak detector properly, read the manufacturer's
operating instructions and perform any specified maintenance.
1. Position the probe approximately 5 mm (3/16 in) away from the
point to be checked as shown.
AHA2 81 A
SHA707EA

AV-2Revision: August 20072004 QX56 “VIEW” MODE ..................................................... 70
“HEADING” MODE .............................................. 71
“NEARBY DISPLAY ICONS” MODE ................... 71
“SAVE CURRENT LOCATION” MODE ............... 71
“ADJUST CURRENT LOCATION” MODE ........... 71
“AUTO RE-ROUTE” MODE ................................. 72
“AVOID AREA SETTINGS” MODE ...................... 72
“CLEAR MEMORY” MODE ................................. 72
“EDIT ADDRESS BOOK” MODE ........................ 73
“GPS INFORMATION” MODE ............................. 73
“QUICK STOP CUSTOMER SETTING” MODE ... 73
“SET AVERAGE SPEED” MODE ........................ 73
“TRACKING” MODE ............................................ 74
GUIDANCE VOLUME ......................................... 74
DISPLAY WITH PUSHED “TRIP” BUTTON ........ 74
TRIP 1 OR TRIP 2 ............................................... 75
FUEL ECONOMY ................................................ 75
MAINTENANCE .................................................. 75
ENGINE OIL OR TIRE ROTATION ..................... 75
TIRE PRESSURE ................................................ 76
WARNING INDICATIONS ................................... 76
CAN Communication System Description .............. 76
Component Parts Location ..................................... 77
Schematic ............................................................... 78
Wiring Diagram —NAVI— ....................................... 79
Schematic ............................................................... 86
Wiring Diagram — COMM — ................................. 87
Terminals and Reference Value for NAVI Control
unit .......................................................................... 90
Terminals and Reference Value for Display Control
unit .......................................................................... 92
Terminals and Reference Value for Display unit ..... 96
Terminals and Reference Value for AV Switch ....... 98
Terminals and Reference Value for BCM ................ 99
On Board Self-Diagnosis Function .......................101
DESCRIPTION ..................................................101
DIAGNOSIS ITEM .............................................101
Self-Diagnosis Mode (DCU) .................................101
OPERATION PROCEDURE ..............................101
SELF–DIAGNOSIS RESULT .............................103
Self-Diagnosis Mode (NAVI) .................................104
OPERATION PROCEDURE ..............................104
SELF–DIAGNOSIS RESULT .............................105
Confirmation/Adjustment Mode ............................107
OPERATION PROCEDURE ..............................107
DISPLAY DIAGNOSIS .......................................108
VEHICLE SIGNALS ...........................................108
NAVIGATION .....................................................109
DISPLAY DIAGNOSIS .......................................109
VEHICLE SIGNALS ...........................................110
HISTORY OF ERRORS ....................................110
DIAGNOSIS BY HISTORY OF ERRORS ..........110
NAVIGATION .....................................................112
CAN DIAG SUPPORT MONITOR ........................114
OPERATION PROCEDURE ..............................114
AV Switch Self-Diagnosis Function .......................115
Power Supply and Ground Circuit Check for NAVI
Control Unit ...........................................................116
Power Supply and Ground Circuit Check for Display Control Unit ...........................................................117
Power Supply and Ground Circuit Check for Display
Unit ........................................................................118
Power Supply and Ground Circuit Check for AV
Switch ................................................................... 120
Vehicle Speed Signal Check for NAVI Control Unit . 121
Vehicle Speed Signal Check for Display Control Unit . 122
Illumination Signal Check for NAVI Control Unit ... 123
Illumination Signal Check for Display Control Unit . 123
Ignition Signal Check for NAVI Control Unit .......... 123
Ignition Signal Check for Display Control Unit ...... 124
Reverse Signal Check for NAVI Control Unit ........ 124
Reverse Signal Check for Display Control Unit .... 124
AV Communication Line Check (Between Display
Control Unit and NAVI Control Unit) ...................... 125
Audio Communication Line Check (Between Dis-
play Control Unit and Audio Unit) .......................... 126
Display Communication Line Check (Between Dis-
play Control Unit and Display Unit) ....................... 128
AV Communication Line Check (Between Display
Control Unit and AV Switch) .................................. 130
CAN Communication Line Check ......................... 131
If NAVI Control Unit Detects That DVD-ROM Map
is Not Inserted ....................................................... 131
If NAVI Control Unit Detects That Inserted DVD-
ROM Map Malfunctioning or If It is Impossible to
Load Data from DVD-ROM Map ........................... 131
If Connection Between NAVI Control Unit and GPS
Antenna is Malfunctioning ..................................... 132
Operating Screen for Audio and A/C is Not Dis-
played When Showing NAVI Screen ..................... 132
Color of RGB Image is Not Proper (Only NAVI
Screen Looks Bluish) ............................................ 134
Color of RGB Image is Not Proper (Only NAVI
Screen Looks Reddish) ......................................... 135
Color of RGB Image is Not Proper (Only NAVI
Screen Looks Yellowish) ....................................... 136
Color of RGB Image is Not Proper (All Screen Looks
Bluish) ................................................................... 137
Color of RGB Image is Not Proper (All Screen Looks
Reddish) ................................................................ 138
Color of RGB Image is Not Proper (All Screen Looks
Yellowish) .............................................................. 139
NAVI Screen is Rolling .......................................... 140
Guide Sound is Not Heard .................................... 142
Screen is Not Shown ............................................ 143
A/C Screen is Not Shown (NAVI Screen is Shown) . 143
FUEL ECONOMY Screen is Not Shown ............... 143
Average Fuel Economy Displayed is Not Shown (“
*** ” is Shown) ....................................................... 143
Distance to Empty Displayed is Not Shown (“ *** ”
is Shown) .............................................................. 144
Driving Distance or Average Speed Displayed is Not
Shown (“ *** ” is Shown) ....................................... 144
WARNING DOOR OPEN Screen is Not Shown ... 144
Unable to Operate All of AV Switches (Unable to
Start Self-Diagnosis) ............................................. 145
Audio Does Not Work ........................................... 145
Navigation System Does Not Activate .................. 145

AV-74
NAVIGATION SYSTEM
Revision: August 20072004 QX56
“TRACKING” MODE

To delete the tracking marks on the map, select “Off”.

To leave the tracking marks on the map, select “On”.
NOTE:
When a trail display is turned OFF, trail data is erased from the mem-
ory.
GUIDANCE VOLUME
Description
Following guidance volume settings can be changed.
Activation/Deactivation Setting

The voice prompt can be turned on/off by pressing the “Guidance Volume” button.
Voice Volume Setting

Volume of the voice can be controlled by tilting the joystick to left/right.
DISPLAY WITH PUSHED “TRIP” BUTTON

When the “TRIP” button is pushed, the following items will display on the screen.

Warning message (if there are any) →TRIP1→TRIP2→FUEL ECONOMY→MAINTENANCE→OFF.
SKIA0559E
SKIA4497E
Display items Display/Setting contentsReference
page
Trip 1 o r Trip 2Elapsed TimeDisplays driving time with a range of 0000:00:00 to
9999:59:59.
AV- 7 5
Driving Distance
[(km) or (miles)] Displays driving distance with a range of 00000.0 to
99999.9.
Average speed
[(km/h) or (MPH)]Displays average speed with a range of 000.0 to 999.9.
Fuel EconomyAverage Fuel Economy
[(MPG) or (l/100km)]Displays fuel economy with ignition switch ON, average
fuel economy each 30 seconds.
AV- 7 5
Distance to Empty
[(km) or (miles)]Displays possible driving distance with remaining fuel.
Fuel Economy [(MPG)
or (l/100km)]Displays fuel economy each approx. 100 ms.
Maintenance Engine oilMaintenance intervals of engine oil and setting of oil
change cycle.
AV- 7 5
Tire rotationMaintenance intervals of tire and setting of tire replace-
ment cycle.
Tire pressure Tire pressure displayed as tire pressure information.

NAVIGATION SYSTEM
AV-75
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Revision: August 20072004 QX56
TRIP 1 OR TRIP 2

Elapsed time, Driving distance and Average speed are dis-
played as Trip 1 information or Trip 2 information.

The way to reset is by pushing the “Reset” switch or by pushing
“TRIP” button more than 1.5 seconds.
FUEL ECONOMY

Average Fuel Economy, Distance to Empty, Fuel Economy are
displayed as Fuel Economy information.

The way to reset is by pushing the “Reset” switch or by pushing
“TRIP” button more than 1.5 seconds.
MAINTENANCE

Engine Oil, Tire Rotation and Tire pressure are displayed as
Maintenance information.
NOTE:
In a case of a vehicle with low tire pressure warning control unit,
“Tire Pressure” switch is displayed.
ENGINE OIL OR TIRE ROTATION

Possible to set up interval of engine oil and tire rotation by tilting
joystick right and left.
WKIA1953E
WKIA1954E
WKIA1955E
WKIA1956E

DI-1
DRIVER INFORMATION SYSTEM
K ELECTRICAL
CONTENTS
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Revision: August 20072004 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 ........................................................... 30
WARNING LAMPS .................................................... 31
Schematic ............................................................... 31
Wiring Diagram — WARN — .................................. 32
Oil Pressure Warning Lamp Stays Off (Ignition
Switch ON) ............................................................. 38
Oil Pressure Warning Lamp Does Not Turn Off (Oil
Pressure Is Normal) ................................................ 40
A/T INDICATOR ........................................................ 41
Wiring Diagram — AT/IND — ................................. 41
A/T Indicator Does Not Illuminate ........................... 42
WARNING CHIME ..................................................... 43
Component Parts and Harness Connector Location ... 43
System Description ................................................. 44
FUNCTION .......................................................... 44
IGNITION KEY WARNING CHIME ..................... 44
LIGHT WARNING CHIME ................................... 44
SEAT BELT WARNING CHIME ........................... 44

DI-14
COMBINATION METERS
Revision: August 20072004 QX56
Next test requested Sc1XXDisplays 8-bit software
configuration value in Hex
format.Bit Coding
7-3 = reserved for future use
2 = TCS/VDC 0 = not present
1 = present
1 = Shift type 0 = Column shift
1 = Floor shift
0 = ICC 0 = not present
1 = present
Next test requested Sc2XXDisplays 8-bit software
configuration value in Hex
format.Bit coding
7-0 = Reserved for future use
Next test requested EprXXDisplays 8-bit software
configuration value in Hex
format.Bit Coding
7-2 = reserved for future use
1 = A/T Oil Temp (gauge)
0 = not present
1 = present
1 = Odo Units 0 = kilometers
1 = miles
Next test requested 1nFXXDisplays 8-bit market info
value in Hex format.$31 = USA
$2A = Canada
Next test requested cYLXXDisplays 8-bit engine con-
figuration value in Hex
format.$08 = 8 cylinder
$06 = 6 cylinder
Next test requested FFXXXXDisplays 16-bit fuel flow
constant "Q" in tenths of
cc/min in Hex format.$0000 - $FFFF
Next test requested tFDisplays 16-bit tire factor
"A" in hundredths in Hex
format.$0000 - $FFFF
Next test requested ot1XXDisplays oil pressure tell-
tale "on" threshold in A/D
counts in Hex format.$00 - $FF
Next test requested ot0XXDisplays oil pressure tell-
tale "off" threshold in A/D
counts in Hex format.$00 - $FF
Next test requested XXXXXRaw uncompensated
english speed value in
hundredths of MPH.
Speedometer indicates
present speed.Will display "-----" if message is
not received. Will display
"99999" if data received is
invalid
Next test requested XXXXXRaw uncompensated
metric speed value in
hundredths of KPH.
Speedometer indicates
present speed.Will display "-----" if message is
not received. Will display
"99999" if data received is
invalid
Next test requested tXXXXTachometer value in
RPM. Tachometer indi-
cates present RPM.Will display "-----" if message is
not received.
Next test requested F1 XXXXPresent ratioed fuel level
A/D input 1 in decimal for-
mat. Fuel gauge indicates
present filtered level.000-009 = Short circuit
010-254 = Normal range
255 = Open circuit
--- = Missing 5 seconds
Next test requested XXXCLast temperature gauge
input value in degrees C.
Temperature gauge indi-
cates present filtered tem-
perature.Will display "---"C if message is
not received.
Will display "999" if data
received is invalid. Event Odometer Display Description of Test/Data Notes: