2004 INFINITI QX56 Engine cooling system

ENGINE MAINTENANCE
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3. Open the radiator drain plug at the bottom of the radiator, and
remove the radiator filler cap. This is the only step required
when partially draining the cooling system (radiator only).
CAUTION:
Do not to allow the coolant to contact the drive belts.
4. When draining all of the coolant in the system for engine
removal or repair, it is necessary to drain the cylinder block.
Remove the RH cylinder block drain plug to drain the right bank
and the oil cooler hose to drain the left bank as shown.
5. Remove the reservoir tank to drain the engine coolant, then clean the reservoir tank before installing it.
6. Check the drained coolant for contaminants such as rust, corrosion or discoloration.
If the coolant is contaminated, flush the engine cooling system. Refer to MA-14, "
FLUSHING COOLING
SYSTEM" .
REFILLING ENGINE COOLANT
1. Close the radiator drain plug. Install the reservoir tank, cylinder block drain plug, and the oil cooler hose, if
removed for a total system drain or for engine removal or repair.

The radiator must be completely empty of coolant and water.

Apply sealant to the threads of the cylinder block drain plug. Use Genuine High Performance Thread
Sealant or equivalent. Refer to GI-45, "
RECOMMENDED CHEMICAL PRODUCTS AND SEALANTS" .
2. Set the vehicle heater controls to the full HOT and heater ON position. Turn the vehicle ignition ON with
the engine OFF as necessary to activate the heater mode.
3. Remove the vented reservoir cap and replace it with a non-vented reservoir cap before filling the cooling
system.
WBIA0391E
PBIC0146E
WBIA0392E
Radiator drain plug : Refer to CO-10, "RADIATOR" .
RH cylinder block drain plug : Refer to EM-73, "
CYLINDER BLOCK" .

MA-14
ENGINE MAINTENANCE
Revision: August 20072004 QX56
4. Install the Tool by installing the radiator cap adapter onto the
radiator neck opening. Then attach the gauge body assembly
with the refill tube and the venturi assembly to the radiator cap
adapter.
5. Insert the refill hose into the coolant mixture container that is
placed at floor level. Make sure the ball valve is in the closed
position.

Use Genuine NISSAN Long Life Anti-freeze coolant or equiv-
alent, mixed 50/50 with distilled water or demineralized water.
Refer to MA-11, "
ANTI-FREEZE COOLANT MIXTURE
RATIO" .
6. Install an air hose to the venturi assembly, the air pressure must
be within specification.
CAUTION:
The compressed air supply must be equipped with an air
dryer.
7. The vacuum gauge will begin to rise and there will be an audible hissing noise. During this process open
the ball valve on the refill hose slightly. Coolant will be visible rising in the refill hose. Once the refill hose is
full of coolant, close the ball valve. This will purge any air trapped in the refill hose.
8. Continue to draw the vacuum until the gauge reaches 28 inches
of vacuum. The gauge may not reach 28 inches in high altitude
locations, refer to the vacuum specifications based on the alti-
tude above sea level.
9. When the vacuum gauge has reached the specified amount, disconnect the air hose and wait 20 seconds
to see if the system loses any vacuum. If the vacuum level drops, perform any necessary repairs to the
system and repeat steps 6 - 8 to bring the vacuum to the specified amount. Recheck for any leaks.
10. Place the coolant container (with the refill hose inserted) at the same level as the top of the radiator. Then
open the ball valve on the refill hose so the coolant will be drawn up to fill the cooling system. The cooling
system is full when the vacuum gauge reads zero.
CAUTION:
Do not allow the coolant container to get too low when filling, to avoid air from being drawn into
the cooling system.
11. Remove the Tool from the radiator neck opening and install the radiator cap.
12. Remove the non-vented reservoir cap.
13. Fill the cooling system reservoir tank to the specified level. Run the engine to warm up the cooling system
and top up the system as necessary before installing the vented reservoir cap.
FLUSHING COOLING SYSTEM
1. Drain the water from the engine cooling system. Refer to MA-12, "DRAINING ENGINE COOLANT" .
2. Fill the radiator and the reservoir tank (to the “MAX” line), with water. Reinstall the radiator cap and leave
the vented reservoir cap off.Tool number : KV991J0070 (J-45695)
Cooling system capacity
(with reservoir tank): Refer to MA-10, "
Fluids
and Lubricants" .
Compressed air
supply pressure: 5.7 - 8.5 kPa (5.6 - 8.4 kg/cm
2
, 80 - 120 psi)
LLIA0058E
Altitude above sea level Vacuum gauge reading
0 - 100 m (328 ft) : 28 inches of vacuum
300 m (984 ft) : 27 inches of vacuum
500 m (1,641 ft) : 26 inches of vacuum
1,000 m (3,281 ft) : 24 - 25 inches of vacuum
LLIA0057E

ENGINE MAINTENANCE
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3. Run the engine until it reaches normal operating temperature.
4. Press the engine accelerator two or three times under no-load.
5. Stop the engine and wait until it cools down.
6. Drain the water from the engine cooling system. Refer to MA-12, "
DRAINING ENGINE COOLANT" .
7. Repeat steps 2 through 6 until clear water begins to drain from the radiator.
Checking Fuel LinesELS00107
Inspect the fuel lines and fuel tank for improper mounting, leaks,
cracks, damage, loose connections, chafing, or deterioration.
As necessary, repair or replace any faulty parts.
Changing Fuel FilterELS00108
The fuel filter is part of the fuel level sensor unit, fuel filter and fuel pump assembly. Refer to FL-5, "FUEL
LEVEL SENSOR UNIT, FUEL FILTER AND FUEL PUMP ASSEMBLY" .
WA RN ING:
Before replacing the fuel filter, release the fuel pressure from the fuel system. Refer to EC-46, "
FUEL
PRESSURE RELEASE" .
Changing Engine Air Cleaner FilterELS00109
VISCOUS PAPER TYPE
NOTE:

The viscous paper type filter does not need cleaning between replacement intervals.

Replace the air filter as necessary for required maintenance.
1. Remove the air duct and resonator assembly (inlet).
2. Remove the air cleaner case (upper).
3. Remove the air cleaner filter from the air cleaner case (lower).
4. Install the new air cleaner filter in the air cleaner case (lower).
SM A80 3A
1. Air cleaner case (upper) 2. Air cleaner filter 3. Air cleaner case (lower)
4. Air duct and resonator assembly
LBIA0394E

CHASSIS AND BODY MAINTENANCE
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5. Insert the first new in-cabin microfilter into the front heater and
cooling unit assembly housing and slide it over to the right.
Insert the second new in-cabin microfilter into the front heater
and cooling unit assembly housing.
NOTE:
The in-cabin microfilters are marked with air flow arrows. The
end of the microfilter with the arrow should face the rear of the
vehicle. The arrows should point downward.
6. Install the in-cabin microfilter cover.
7. Install the glove box assembly in reverse order of removal.
8. Install the instrument lower cover RH.
Checking Exhaust SystemELS0010F
Check exhaust pipes, muffler and mounting for improper attachment,
leaks, cracks, damage, loose connections, chafing or deterioration.
Checking A/T FluidELS001JM
1. Warm up the engine.
2. Check for any fluid leakage.
3. Remove the tightening bolt for the ATF level gauge.
LJIA0148E
LJIA0134E
Upper glove box screws : 3.5 N·m (0.36 kg-m, 31 in-lb)
Lower glove box screws : 3.5 N·m (0.36 kg-m, 31 in-lb)
LLIA0072E
SM A211 A

CHASSIS AND BODY MAINTENANCE
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b. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T” with CONSULT-II.
c. Read out the value of “ATF TEMP 1”.
7. Re-check fluid level at fluid temperatures of approximately 65°C
(149°F) using “HOT” range on A/T fluid level gauge.
CAUTION:

When wiping away the fluid level gauge, always use lint-
free paper, not a cloth one.

To check fluid level, insert the ATF level gauge until the
cap contacts the end of the charging pipe, with the gauge
reversed from the normal attachment conditions as
shown.
8. Check fluid condition.

If fluid is very dark or smells burned, refer to check operation
of A/T. Flush cooling system after repair of A/T.

If ATF contains frictional material (clutches, bands, etc.),
replace radiator and flush cooler line using cleaning solvent
and compressed air after repair of A/T. Refer to CO-10,
"RADIATOR" and AT-15, "A/T Fluid Cooler Cleaning" .
9. Install the removed ATF level gauge into the fluid charging pipe.
Changing A/T FluidELS001JN
1. Increase ATF temperature by 80°C (176°F) once.
2. Stop the engine.
3. Remove the tightening bolt for the ATF level gauge.
4. Drain ATF from drain plug and refill with new ATF. Always refill same volume with drained fluid.

To replace the ATF, pour in new fluid at the charging pipe with the engine idling and at the same time
drain the old fluid from the radiator cooler hose return side.

When the color of the fluid coming out is about the same as the color of the new fluid, the replacement
is complete. The amount of new transmission fluid to use should be 30 to 50% increase of the stipu-
lated amount.
CAUTION:

Use only specified ATF fluid. Do not mix with other fluid.

Using ATF other than the specified ATF fluid will cause deterioration in driveability and auto-
matic transmission durability, and may damage the automatic transmission, which is not cov-
ered by the warranty.

When filling ATF, take care not to splash any heat generating parts such as the exhaust.
5. Increase ATF temperature by 80°C (176°F) once.
6. Check fluid level and condition. Refer to MA-21, "
Checking A/T Fluid" . If fluid is still dirty, repeat step 2.
through 5.
7. Install the removed ATF level gauge in the fluid charging pipe.
WLIA0014E
Level gauge bolt : Refer to AT-13, "A/T FLUID" .
SCIA1684E
ATF fluid capacity and specification : Refer to MA-10, "Fluids and Lubricants" .
Drain plug : Refer to AT-13, "
A/T FLUID" .
Level gauge bolt : Refer to AT- 1 3 , "
A/T FLUID" .

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
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IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
PFP:284B7
System DescriptionEKS007NN

IPDM E/R (Intelligent Power Distribution Module Engine Room) integrates the relay box and fuse block
which were originally placed in engine compartment. It controls integrated relays via IPDM E/R control cir-
cuits.

IPDM E/R-integrated control circuits perform ON-OFF operation of relays, CAN communication control,
etc.

It controls operation of each electrical component via ECM, BCM and CAN communication lines.
CAUTION:
None of the IPDM E/R integrated relays can be removed.
SYSTEMS CONTROLLED BY IPDM E/R
1. Lamp control
Using CAN communication lines, it receives signals from the BCM and controls the following lamps:

Headlamps (Hi, Lo)

Parking lamps

Tail lamps

Front fog lamps
2. Wiper control
Using CAN communication lines, it receives signals from the BCM and controls the front wipers.
3. Rear window defogger relay control
Using CAN communication lines, it receives signals from the BCM and controls the rear window defogger
relay.
4. A/C compressor control
Using CAN communication lines, it receives signals from the ECM and controls the A/C compressor
(magnetic clutch).
5. Starter control
Using CAN communication lines, it receives signals from the ECM and controls the starter relay.
6. Cooling fan control
Using CAN communication lines, it receives signals from the ECM and controls the cooling fan relays.
7. Horn control
Using CAN communication lines, it receives signals from the BCM and controls the horn relay.
CAN COMMUNICATION LINE CONTROL
With CAN communication, by connecting each control unit using two communication lines (CAN L-line, CAN
H-line), it is possible to transmit a maximum amount of information with minimum wiring. Each control unit can
transmit and receive data, and reads necessary information only.
1. Fail-safe control

When CAN communication with other control units is impossible, IPDM E/R performs fail-safe control.
After CAN communication returns to normal operation, it also returns to normal control.

Operation of control parts by IPDM E/R during fail-safe mode is as follows:
Controlled system Fail-safe mode
Headlamp

With the ignition switch ON, the headlamp (low) is ON.

With the ignition switch OFF, the headlamp (low) is OFF.
Tail and parking lamps

With the ignition switch ON, the tail and parking lamps are ON.

With the ignition switch OFF, the tail and parking lamps are OFF.
Cooling fan

With the ignition switch ON, the cooling fan HI operates.

With the ignition switch OFF, the cooling fan stops.
Front wiperUntil the ignition switch is turned off, the front wiper LO and HI remains in the same status it
was in just before fail−safe control was initiated.
Rear window defogger Rear window defogger relay OFF

IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
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Auto Active TestEKS007NR
DESCRIPTION

In auto active test mode, operation inspection can be performed when IPDM E/R sends a drive signal to
the following systems:
–Rear window defogger
–Front wipers
–Tail and parking lamps
–Front fog lamps
–Headlamps (Hi, Lo)
–A/C compressor (magnet clutch)
–Cooling fan
OPERATION PROCEDURE
1. Close hood and front door RH, and lift wiper arms away from windshield (to prevent glass damage by
wiper operation).
NOTE:
When auto active test is performed with hood opened, sprinkle water on windshield beforehand.
2. Turn ignition switch OFF.
3. Turn ignition switch ON and, within 20 seconds, press front door switch LH 10 times. Then turn ignition
switch OFF.
4. Turn ignition switch ON within 10 seconds after ignition switch OFF.
5. When auto active test mode is actuated, horn chirps once.
6. After a series of operations is repeated three times, auto active test is completed.
NOTE:
When auto active test mode has to be cancelled halfway, turn ignition switch OFF.
CAUTION:
Be sure to perform BL-93, "
Door Switch Check" when the auto active test cannot be performed.
INSPECTION IN AUTO ACTIVE TEST MODE

When auto active test mode is actuated, the following seven steps are repeated three times.
Cornering lamp output CORNERING LAMP —
Horn output HORN With a certain ON-OFF operation, the horn relay can be operated.Test name CONSULT-II screen display Description
WKIA1972E

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IPDM E/R (INTELLIGENT POWER DISTRIBUTION MODULE ENGINE ROOM)
Revision: August 20072004 QX56
Concept of Auto Active Test

IPDM E/R actuates auto active test mode when it receives door switch signal from BCM via CAN commu-
nication line. Therefore, when auto active test mode is activated successfully, CAN communication
between IPDM E/R and BCM is normal.

If any of the systems controlled by IPDM E/R cannot be operated, possible cause can be easily diagnosed
using auto active test.
Diagnosis chart in auto active test mode
Symptom Inspection contents Possible cause
Rear window defogger
does not operate.Perform auto active
test. Does rear win-
dow defogger oper-
ate?YES

BCM signal input circuit
NO

Rear window defogger relay

Open circuit of rear window defogger

IPDM E/R malfunction

Harness or connector malfunction between IPDM E/R and rear window
defogger
Any of front wipers, tail
and parking lamps, front
fog lamps, and head-
lamps (Hi, Lo) do not
operate.Perform auto active
test. Does system in
question operate?YES

BCM signal input system
NO

Lamp/wiper motor malfunction

Lamp/wiper motor ground circuit malfunction

Harness/connector malfunction between IPDM E/R and system in
question

IPDM E/R (integrated relay) malfunction
A/C compressor does
not operate.Perform auto active
test. Does magnet
clutch operate?YES

BCM signal input circuit

CAN communication signal between BCM and ECM

CAN communication signal between ECM and IPDM E/R
NO

Magnet clutch malfunction

Harness/connector malfunction between IPDM E/R and magnet clutch

IPDM E/R (integrated relay) malfunction
Cooling fan does not
operate.Perform auto active
test. Does cooling fan
operate?YES

ECM signal input circuit

CAN communication signal between ECM and IPDM E/R
NO

Cooling fan motor malfunction

Harness/connector malfunction between IPDM E/R and cooling fan
motor

IPDM E/R (integrated relay) malfunction