2004 INFINITI QX56 ABS

AT-36
A/T CONTROL SYSTEM
Revision: August 20072004 QX56
Lock-up Applied

In the lock-up applied state, the torque converter clutch control valve is set into the locked state by the
torque converter clutch solenoid and lock-up apply pressure is generated.
In this way, the torque converter clutch piston is pressed and coupled.
SMOOTH LOCK-UP CONTROL
When shifting from the lock-up released state to the lock-up applied state, the current output to the torque con-
verter clutch solenoid is controlled with the TCM. In this way, when shifting to the lock-up applied state, the
torque converter clutch is temporarily set to the half-clutched state to reduce the shock.
Half-clutched State

The current output from the TCM to the torque converter clutch solenoid is varied to gradually increase
the torque converter clutch solenoid pressure.
In this way, the lock-up apply pressure gradually rises and while the torque converter clutch piston is put
into half-clutched status, the torque converter clutch piston operating pressure is increased and the cou-
pling is completed smoothly.
Slip Lock-up Control

In the slip region, the torque converter clutch solenoid current is controlled with the TCM to put it into the
half-clutched state. This absorbs the engine torque fluctuation and lock-up operates from low speed.
This raises the fuel efficiency for 4th and 5th gears at both low speed and when the accelerator has a low
degree of opening.

AT-98
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
ATF PRES SW 5 (ON-OFF display) X X X (for D/C solenoid)
ATF PRES SW 6 (ON-OFF display) X X X (for HLR/C solenoid)
PNP SW 1 (ON-OFF display) X — X
PNP SW 2 (ON-OFF display) X — X
PNP SW 3 (ON-OFF display) X — X
PNP SW 4 (ON-OFF display) X — X
SLCT LVR POSI — X XSelector lever position is recognized by the
TCM.
For fail-safe operation, the specific value used
for control is displayed.
1 POSITION SW (ON-OFF display) X — X 1st position switch
OD CONT SW (ON-OFF display) X — X 4th position switch
POWERSHIFT SW (ON-OFF display) X — X
Not mounted but displayed. HOLD SW (ON-OFF display) X — X
MANU MODE SW (ON-OFF display) X — X
NON M-MODE SW (ON-OFF display) X — X
UP SW LEVER (ON-OFF display) X — X
DOWN SW LEVER (ON-OFF display) X — X
SFT UP ST SW (ON-OFF display) — — X
SFT DWN ST SW (ON-OFF display) — — X
ASCD-OD CUT (ON-OFF display) — — X
ASCD-CRUISE (ON-OFF display) — — X
ABS SIGNAL (ON-OFF display) — — X
ACC OD CUT (ON-OFF display) — — X
ICC (Intelligent cruise control)
ACC SIGNAL (ON-OFF display) — — X
TCS GR/P KEEP (ON-OFF display) — — X
TCS SIGNAL 2 (ON-OFF display) — — X
TCS SIGNAL 1 (ON-OFF display) — — X
TCC SOLENOID (A) — X X
LINE PRES SOL (A) — X X
I/C SOLENOID (A) — X X
FR/B SOLENOID (A) — X X
D/C SOLENOID (A) — X X
HLR/C SOL (A) — X X
ON OFF SOL (ON-OFF display) — — X LC/B solenoid
TCC SOL MON (A) — — X
L/P SOL MON (A) — — X
I/C SOL MON (A) — — X
FR/B SOL MON (A) — — X
D/C SOL MON (A) — — X
HLR/C SOL MON (A) — — X
ONOFF SOL MON (ON-OFF display) — — X LC/B solenoidMonitored item (Unit)Monitor Item Selection
Remarks ECU
INPUT
SIGNALSMAIN SIG-
NALSSELEC-
TION
FROM
MENU

PRECAUTIONS
ATC-5
C
D
E
F
G
H
I
K
L
MA
B
AT C
Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EJS002BF
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WA RN ING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Working with HFC-134a (R-134a)EJS002BG
WA RN ING:

CFC-12 (R-12) refrigerant and HFC-134a (R-134a) refrigerant are not compatible. If the refrigerants
are mixed compressor failure is likely to occur. Refer AT C - 5 , "
Contaminated Refrigerant" . To
determine the purity of HFC-134a (R-134a) in the vehicle and recovery tank, use Refrigerant
Recovery/Recycling Recharging equipment and Refrigerant Identifier.

Use only specified lubricant for the HFC-134a (R-134a) A/C system and HFC-134a (R-134a) compo-
nents. If lubricant other than that specified is used, compressor failure is likely to occur.

The specified HFC-134a (R-134a) lubricant rapidly absorbs moisture from the atmosphere. The fol-
lowing handling precautions must be observed:
–When removing refrigerant components from a vehicle, immediately cap (seal) the component to
minimize the entry of moisture from the atmosphere.
–When installing refrigerant components to a vehicle, do not remove the caps (unseal) until just
before connecting the components. Connect all refrigerant loop components as quickly as possi-
ble to minimize the entry of moisture into system.
–Only use the specified lubricant from a sealed container. Immediately reseal containers of lubri-
cant. Without proper sealing, lubricant will become moisture saturated and should not be used.
–Avoid breathing A/C refrigerant and lubricant vapor or mist. Exposure may irritate eyes, nose and
throat. Remove HFC-134a (R-134a) from the A/C system using certified service equipment meeting
requirements of SAE J2210 [HFC-134a (R-134a) recycling equipment], or J2209 [HFC-134a (R-134a)
recovery equipment]. If accidental system discharge occurs, ventilate work area before resuming
service. Additional health and safety information may be obtained from refrigerant and lubricant
manufacturers.
–Do not allow the lubricant NISSAN A/C System Lubricant Type S (DH-PS) to come in contact with
styrofoam parts. Damage may result.
Contaminated RefrigerantEJS002BH
If a refrigerant other than pure HFC-134a (R-134a) is identified in a vehicle, your options are:

Explain to the customer that environmental regulations prohibit the release of contaminated refrigerant
into the atmosphere.

Explain that recovery of the contaminated refrigerant could damage your service equipment and refriger-
ant supply.

Suggest the customer return the vehicle to the location of previous service where the contamination may
have occurred.

BL-166
BODY REPAIR
Revision: August 20072004 QX56
1. Front shock absorber bracket RH/LH
2. Front differential mounting bracket RH/LH
3. 1st cab mounting bracket RH/LH
4. Front side member extension assembly RH/LH
5. 1st crossmember assembly
6. 2nd crossmember assembly
7. Front upper link mounting bracket RH/LH
8. Panhard rod bracket reinforcement
9. Bound bumper bracket RH/LH
10. Front brake hose bracket RH/LH
11. Panhard rod reinforcement
12. 4th crossmember gusset RH/LH
13. 2nd cab mounting bracket RH/LH
14. 3rd cab mounting bracket RH/LH
15. 4th cab mounting reinforcement RH/LH
16. 4th cab mounting bracket RH/LH
17. Rear suspension mounting bracket RH/LH
18. Rear brake hose bracket
19. Rear shock absorber bracket assembly RH/LH
20. Rear bound bumper bracket RH/LH
21. Rear bracket bumper reinforcement RH/LH
22. Cab mounting bracket assembly RH/LH
23. 9th crossmember assembly
24. Exhaust bracket assembly
25. Canister bracket, LH
26. 7th crossmember reinforcement
27. 7th crossmember assembly
28. 6th crossmember assembly
29. 4th crossmember gusset RH/LH
30. 4th crossmember assembly
31. 3rd crossmember assembly
32. Frame assembly

BODY REPAIR
BL-167
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BL
Revision: August 20072004 QX56
Corrosion ProtectionEIS002U5
DESCRIPTION
To provide improved corrosion prevention, the following anti-corrosive measures have been implemented in
NISSAN production plants. When repairing or replacing body panels, it is necessary to use the same anti-cor-
rosive measures.
ANTI-CORROSIVE PRECOATED STEEL (GALVANNEALED STEEL)
To improve repairability and corrosion resistance, a new type of anti-
corrosive precoated steel sheet has been adopted replacing conven-
tional zinc-coated steel sheet.
Galvannealed steel is electroplated and heated to form Zinc-iron
alloy, which provides excellent and long term corrosion resistance
with cationic electrode position primer.
Nissan Genuine Service Parts are fabricated from galvannealed steel. Therefore, it is recommended that
GENUINE NISSAN PARTS or equivalent be used for panel replacement to maintain the anti-corrosive perfor-
mance built into the vehicle at the factory.
PHOSPHATE COATING TREATMENT AND CATIONIC ELECTRODEPOSITION PRIMER
A phosphate coating treatment and a cationic electrode position primer, which provide excellent corrosion pro-
tection, are employed on all body components.
CAUTION:
Confine paint removal during welding operations to an absolute
minimum.
Nissan Genuine Service Parts are also treated in the same manner. Therefore, it is recommended that GENU-
INE NISSAN PARTS or equivalent be used for panel replacement to maintain anti-corrosive performance built
into the vehicle at the factory.
PIIA0093E
PIIA0095E

BODY REPAIR
BL-189
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BL
Revision: August 20072004 QX56
Handling Precautions for PlasticsEIS002U9
HANDLING PRECAUTIONS FOR PLASTICS
1. When repairing and painting a portion of the body adjacent to plastic parts, consider their characteristics
(influence of heat and solvent) and remove them if necessary or take suitable measures to protect them.
2. Plastic parts should be repaired and painted using methods suiting the materials
, characteristics.
Abbre-
viationMaterial nameHeat resisting
temperature
°C (°F)Resistance to gasoline and
solventsOther cautions
PE Polyethylene 60 (140)Gasoline and most solvents are
harmless if applied for a very
short time (wipe up quickly).Flammable
PVC Polyvinyl Chloride 80 (176) Same as above.Poison gas is emitted
when burned.
EPM/
EPDMEthylene Propylene (Diene) rub-
ber80 (176) Same as above. Flammable
TPO/
TPRThermoplastic Olefine/
Thermoplastic Rubber80 (176) Same as above. Flammable
PP Polypropylene 90 (194) Same as above.Flammable, avoid bat-
tery acid.
UP Polyester thermoset 90 (194) Same as above. Flammable
PS Polystyrene 80 (176) Avoid solvents. Flammable
ABSAcrylonitrile Butadiene Styrene
resin80 (176) Avoid gasoline and solvents.
AES Acrylonitrile Ethylene Styrene 80 (176) Same as above.
PMMA Polymethyl Methacrylate 85 (185) Same as above.
AAS Acrylonitrile Acrylic Styrene 85 (185) Same as above.
AS Acrylonitrile Styrene 85 (185) Same as above.
EVA Polyvinyl Ethyl Acetate 90 (194) Same as above.
ASA Acrylonitrile Styrene Acrylate 100 (222) Same as above. Flammable
PPO/
PPEPolyphenylene Oxide/
Polyphenylene Ether110 (230) Same as above.
PC Polycarbonate 120 (248) Same as above.
PAR Polyacrylate 180 (356) Same as above.
L-
LDPELenear Low Density PE 45 (100)Gasoline and most solvents are
harmless.Flammable
PUR Polyurethane 90 (194) Same as above.
TPU Thermoplastic Urethane 110 (230) Same as above.
PPC Polypropylene Composite 115 (239) Same as above. Flammable
POM Polyacetal 120 (248) Same as above. Avoid battery acid.
PBT+P
CPolybutylene Terephtha-
late+Polycarbonate120 (248) Same as above. Flammable
PA Polyamide (Nylon) 140 (284) Same as above.Avoid immersing in wa-
ter.
PBT Polybutylene Terephthalate 140 (284) Same as above.
FRP Fiber Reinforced Plastics 170 (338) Same as above. Avoid battery acid.
PET Polyethylene Terephthalate 180 (356) Same as above.
PEI Polyetherimide 200 (392) Same as above.

PRECAUTIONS
BR-3
C
D
E
G
H
I
J
K
L
MA
B
BR
Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
EFS003P3
The Supplemental Restraint System such as “AIR BAG” and “SEAT BELT PRE-TENSIONER”, used along
with a front seat belt, helps to reduce the risk or severity of injury to the driver and front passenger for certain
types of collision. This system includes seat belt switch inputs and dual stage front air bag modules. The SRS
system uses the seat belt switches to determine the front air bag deployment, and may only deploy one front
air bag, depending on the severity of a collision and whether the front occupants are belted or unbelted.
Information necessary to service the system safely is included in the SRS and SB section of this Service Man-
ual.
WA RN ING:

To avoid rendering the SRS inoperative, which could increase the risk of personal injury or death
in the event of a collision which would result in air bag inflation, all maintenance must be per-
formed by an authorized NISSAN/INFINITI dealer.

Improper maintenance, including incorrect removal and installation of the SRS, can lead to per-
sonal injury caused by unintentional activation of the system. For removal of Spiral Cable and Air
Bag Module, see the SRS section.

Do not use electrical test equipment on any circuit related to the SRS unless instructed to in this
Service Manual. SRS wiring harnesses can be identified by yellow and/or orange harnesses or
harness connectors.
Precautions for Brake SystemEFS0062U

Refer to MA-10, "RECOMMENDED FLUIDS AND LUBRICANTS" for recommended brake fluid.

Do not reuse drained brake fluid.

Be careful not to splash brake fluid on painted areas.

To clean or wash all parts of master cylinder, disc brake caliper and wheel cylinder, use clean brake fluid.

Do not use mineral oils such as gasoline or kerosene. They will ruin rubber parts of the hydraulic system.

Use flare nut wrench when removing and installing brake tube.

Always check tightening torque when installing brake lines.

Before working, turn ignition switch to OFF and disconnect con-
nectors for ABS actuator and electric unit (control unit) or battery
terminals.

Burnish the brake contact surfaces after refinishing or replacing
drums or rotors, after replacing pads or linings, or if a soft pedal
occurs at very low mileage. Refer to BR-25, "
BRAKE BURNISH-
ING PROCEDURE" .
WA RN ING:

Clean brake pads and shoes with a waste cloth, then wipe
with a dust collector.SBR6 86 C

BRAKE FLUID
BR-11
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BR
Revision: August 20072004 QX56
Bleeding Brake SystemEFS003PB
CAUTION:
While bleeding, pay attention to master cylinder fluid level.
1. Turn ignition switch OFF and disconnect ABS actuator and electric unit (control unit) connector or battery
negative cable.
2. Connect a vinyl tube to the rear right bleed valve.
3. Fully depress brake pedal 4 to 5 times.
4. With brake pedal depressed, loosen bleed valve to let the air out, and then tighten it immediately.
5. Repeat steps 3 and 4 until no more air comes out.
6. Tighten bleed valve to the specified torque. Refer to BR-21, "
Components" (front disc brake), BR-27,
"Components" (rear disc brake).
7. Repeat steps 2 through 6, with master cylinder reservoir tank filled at least half way, bleed air from the
front left, rear left, and front right bleed valve.