2004 INFINITI QX56 service

AT-8
PRECAUTIONS
Revision: August 20072004 QX56
Precautions UCS002C3

Before connecting or disconnecting the A/T assembly har-
ness connector, turn ignition switch “OFF” and disconnect
negative battery cable. Because battery voltage is applied
to TCM even if ignition switch is turned “OFF”.

After performing each TROUBLE DIAGNOSIS, perform
“DTC (Diagnostic Trouble Code) CONFIRMATION PROCE-
DURE”.
If the repair is completed the DTC should not be displayed
in the “DTC CONFIRMATION PROCEDURE”.

Always use the specified brand of ATF. Refer to MA-10, "RECOMMENDED FLUIDS AND LUBRICANTS"
.

Use paper rags not cloth rags during work.

After replacing the ATF, dispose of the waste oil using the methods prescribed by law, ordinance, etc.

Before proceeding with disassembly, thoroughly clean the outside of the transaxle. It is important to pre-
vent the internal parts from becoming contaminated by dirt or other foreign matter.

Disassembly should be done in a clean work area.

Use lint-free cloth or towels for wiping parts clean. Common shop rags can leave fibers that could interfere
with the operation of the transaxle.

Place disassembled parts in order for easier and proper assembly.

All parts should be carefully cleaned with a general purpose, non-flammable solvent before inspection or
reassembly.

Gaskets, seals and O-rings should be replaced any time the transaxle is disassembled.

It is very important to perform functional tests whenever they are indicated.

The valve body contains precision parts and requires extreme care when parts are removed and serviced.
Place disassembled valve body parts in order for easier and proper assembly. Care will also prevent
springs and small parts from becoming scattered or lost.

Properly installed valves, sleeves, plugs, etc. will slide along bores in valve body under their own weight.

Before assembly, apply a coat of recommended ATF to all parts. Apply petroleum jelly to protect O-rings
and seals, or hold bearings and washers in place during assembly. Do not use grease.

Extreme care should be taken to avoid damage to O-rings, seals and gaskets when assembling.

After overhaul, refill the transaxle with new ATF.

When the A/T drain plug is removed, only some of the fluid is drained. Old A/T fluid will remain in torque
converter and ATF cooling system.
Always follow the procedures under “Changing A/T Fluid” in the AT section when changing A/T fluid. Refer
to AT-13, "
Changing A/T Fluid" , AT- 1 3 , "Checking A/T Fluid" .
SEF 2 89 H
SEF 2 17 U

PRECAUTIONS
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Service Notice or PrecautionsUCS002C4
ATF COOLER SERVICE
If A/T fluid contains frictional material (clutches, bands, etc.), or if an A/T is repaired, overhauled, or replaced,
inspect and clean the A/T fluid cooler mounted in the radiator or replace the radiator. Flush cooler lines using
cleaning solvent and compressed air after repair. For A/T fluid cooler cleaning procedure, refer to AT-15, "
A/T
Fluid Cooler Cleaning" . For radiator replacement, refer to CO-10, "RADIATOR" .
CHECKING AND CHANGING A/T FLUID SERVICE
Increase ATF temperature by 80°C (176°F) once, and then check ATF level in 65°C (149°F) when adjusting
ATF level.
NOTE:
JA60 uses both systems of a water-cooling and of an air-cooling. Air-cooling system has a by-pass valve.
When ATF temperature is not over 50°C (122°F) with water-cooling system OFF, it does not flow to air-cooling
system. If ATF level is set without the flow of ATF, the level will be 10mm lower than the standard. Therefore,
piping should be filled with ATF when adjusting level.
OBD-II SELF-DIAGNOSIS

A/T self-diagnosis is performed by the TCM in combination with the ECM. The results can be read through
the blinking pattern of the malfunction indicator lamp (MIL). Refer to the table on AT - 9 3 , "
SELF-DIAGNOS-
TIC RESULT MODE" for the indicator used to display each self-diagnostic result.

The self-diagnostic results indicated by the MIL are automatically stored in both the ECM and TCM mem-
ories.
Always perform the procedure on AT-40, "
HOW TO ERASE DTC" to complete the repair and avoid
unnecessary blinking of the MIL.
For details of OBD-II, refer to AT-39, "
ON BOARD DIAGNOSTIC (OBD) SYSTEM" .

Certain systems and components, especially those related to OBD, may use the new style slide-
locking type harness connector. For description and how to disconnect, refer to PG-68, "
HAR-
NESS CONNECTOR" .
Wiring Diagrams and Trouble DiagnosisUCS002C5
When you read wiring diagrams, refer to the following:

GI-15, "How to Read Wiring Diagrams".

PG-4, "POWER SUPPLY ROUTING CIRCUIT" for power distribution circuit.
When you perform trouble diagnosis, refer to the following:

GI-11, "How to Follow Trouble Diagnoses".

GI-27, "How to Perform Efficient Diagnosis for an Electrical Incident".

AT-10
PREPARATION
Revision: August 20072004 QX56
PREPARATIONPFP:00002
Special Service ToolsUCS002C6
The actual shapes of Kent-Moore tools may differ from those of special service tools illustrated here.
Tool number
(Kent-Moore No.)
Tool nameDescription
ST2505S001
(J-34301-C)
Oil pressure gauge set
1 ST25051001
(—)
Oil pressure gauge
2 ST25052000
(—)
Hose
3 ST25053000
(—)
Joint pipe
4 ST25054000
(—)
Adapter
5 ST25055000
(—)
AdapterMeasuring line pressure
KV31103600
(J-45674)
Joint pipe adapter
(With ST25054000)Measuring line pressure
ST33400001
(J-26082)
Drift
a: 60 mm (2.36 in) dia.
b: 47 mm (1.85 in) dia.

Installing rear oil seal (2WD models)

Installing oil pump housing oil seal
KV31102400
(J-34285 and J-34285-87)
Clutch spring compressor
a: 320 mm (12.60 in)
b: 174 mm (6.85 in)Installing reverse brake return spring retainer
ZZA0600D
ZZA1227D
NT086
NT423

AT-12
PREPARATION
Revision: August 20072004 QX56
Commercial Service ToolsUCS002C7
Tool nameDescription
Power toolLoosening bolts and nuts
Drift
a: 22 mm (0.87 in) dia.Installing manual shaft seals
Drift
a: 64 mm (2.52 in) dia.Installing rear oil seal (4WD models)
PBIC0190E
NT083
SCIA5338E

A/T FLUID
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A/T Fluid Cooler CleaningUCS002CA
Whenever an automatic transmission is repaired, overhauled, or replaced, the A/T fluid cooler mounted in the
radiator must be inspected and cleaned.
Metal debris and friction material, if present, can become trapped in the A/T fluid cooler. This debris can con-
taminate the newly serviced A/T or, in severe cases, can block or restrict the flow of A/T fluid. In either case,
malfunction of the newly serviced A/T may result.
Debris, if present, may build up as A/T fluid enters the cooler inlet. It will be necessary to back flush the cooler
through the cooler outlet in order to flush out any built up debris.
A/T FLUID COOLER CLEANING PROCEDURE
1. Position an oil pan under the automatic transmission's inlet and outlet cooler hoses.
2. Identify the inlet and outlet fluid cooler hoses.
3. Disconnect the fluid cooler inlet and outlet rubber hoses from the
steel cooler tubes or bypass valve.
NOTE:
Replace the cooler hoses if rubber material from the hose
remains on the tube fitting.
4. Allow any A/T fluid that remains in the cooler hoses to drain into
the oil pan.
5. Insert the extension adapter hose of a can of Transmission
Cooler Cleaner (Nissan P/N 999MP-AM006) into the cooler out-
let hose.
CAUTION:

Wear safety glasses and rubber gloves when spraying
the Transmission Cooler Cleaner.

Spray cooler cleaner only with adequate ventilation.

Avoid contact with eyes and skin.

Do not breath vapors or spray mist.
6. Hold the hose and can as high as possible and spray Transmis-
sion Cooler Cleaner in a continuous stream into the cooler outlet
hose until fluid flows out of the cooler inlet hose for 5 seconds.
7. Insert the tip of an air gun into the end of the cooler outlet hose.
8. Wrap a shop rag around the air gun tip and of the cooler outlet
hose.
9. Blow compressed air regulated to 5 - 9 kg/cm
2 (70 - 130 psi) through the cooler outlet hose for 10 sec-
onds to force out any remaining fluid.
10. Repeat steps 5 through 9 three additional times.
11. Position an oil pan under the banjo bolts that connect the fluid cooler steel lines to the transmission.
12. Remove the banjo bolts.
13. Flush each steel line from the cooler side back toward the transmission by spraying Transmission Cooler
Cleaner in a continuous stream for 5 seconds.
SCIA3830E
SCIA3831E
SCIA3832E

A/T FLUID
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A/T FLUID COOLER INSPECTION PROCEDURE
1. Inspect the coffee filter for debris.
a. If small metal debris less than 1mm (0.040 in) in size or metal
powder is found in the coffee filter, this is normal. If normal
debris is found, the A/T fluid cooler/radiator can be re-used and
the procedure is ended.
b. If one or more pieces of debris are found that are over 1mm
(0.040 in) in size and/or peeled clutch facing material is found in
the coffee filter, the fluid cooler is not serviceable. The A/T fluid
cooler/radiator must be replaced and the inspection procedure is
ended. Refer to CO-10, "
RADIATOR" .
A/T FLUID COOLER FINAL INSPECTION
After performing all procedures, ensure that all remaining oil is cleaned from all components.
SCIA2967E
SCIA5257E

TROUBLE DIAGNOSIS
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Revision: August 20072004 QX56
How To Perform Trouble Diagnosis For Quick and Accurate RepairUCS002CT
INTRODUCTION
The TCM receives a signal from the vehicle speed sensor, accelerator pedal position sensor (throttle position
sensor) or PNP switch and provides shift control or lock-up control via A/T solenoid valves.
The TCM also communicates with the ECM by means of a signal
sent from sensing elements used with the OBD-related parts of the
A/T system for malfunction-diagnostic purposes. The TCM is capa-
ble of diagnosing malfunctioning parts while the ECM can store mal-
functions in its memory.
Input and output signals must always be correct and stable in the
operation of the A/T system. The A/T system must be in good oper-
ating condition and be free of valve seizure, solenoid valve malfunc-
tion, etc.
It is much more difficult to diagnose a error that occurs intermittently
rather than continuously. Most intermittent errors are caused by poor
electric connections or improper wiring. In this case, careful check-
ing of suspected circuits may help prevent the replacement of good
parts.
A visual check only may not find the cause of the errors. A road test
with CONSULT-II (or GST) or a circuit tester connected should be
performed. Follow the AT-46, "
WORK FLOW" .
Before undertaking actual checks, take a few minutes to talk with a
customer who approaches with a driveability complaint. The cus-
tomer can supply good information about such errors, especially
intermittent ones. Find out what symptoms are present and under
what conditions they occur. A “Diagnostic Worksheet” as shown on
the example (Refer to AT- 4 7
) should be used.
Start your diagnosis by looking for “conventional” errors first. This will
help troubleshoot driveability errors on an electronically controlled
engine vehicle.
Also check related Service bulletins.
SAT6 3 1IB
SAT6 3 2I
SEF 2 34 G

TROUBLE DIAGNOSIS
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DIAGNOSTIC WORKSHEET
Information From Customer
KEY POINTS

WHAT..... Vehicle & A/T model

WHEN..... Date, Frequencies

WHERE..... Road conditions

HOW..... Operating conditions, Symptoms
Diagnostic Worksheet Chart
Customer name MR/MS Model & Year VIN
Trans. Model Engine Mileage
Malfunction Date Manuf. Date In Service Date
Frequency❏ Continuous❏ Intermittent ( times a day)
Symptoms❏ Vehicle does not move. (❏ Any position❏ Particular position)
❏ No up-shift (❏ 1st → 2nd❏ 2nd → 3rd❏ 3rd → 4th ❏ 4th → 5th)
❏ No down-shift (❏ 5th → 4th ❏ 4th → 3rd❏ 3rd → 2nd❏ 2nd → 1st)
❏ Lock-up malfunction
❏ Shift point too high or too low.
❏ Shift shock or slip (❏ N → D❏ Lock-up❏ Any drive position)
❏ Noise or vibration
❏ No kick down
❏ No pattern select
❏ Others
()
AT CHECK indicator lamp Blinks for about 8 seconds.
❏ Continuously lit❏ Not lit
Malfunction indicator lamp (MIL)❏ Continuously lit❏ Not lit
1❏ Read the item on “cautions concerning fail-safe and understand the customer's complaint.AT- 4 3
2❏ ATF inspection
AT- 5 8❏ Leak (Repair leak location.)
❏ Sta te
❏ Amount
3❏ Stall test and line pressure test
AT- 5 8
, AT-
59
❏ Stall test
❏ Torque converter one-way clutch
❏ Front brake
❏ High and low reverse clutch
❏ Low coast brake
❏ Forward brake
❏ Reverse brake
❏ Forward one-way clutch❏ 1st one-way clutch
❏ 3rd one-way clutch
❏ Engine
❏ Line pressure low
❏ Except for input clutch and direct
clutch, clutches and brakes OK
❏ Line pressure inspection - Suspected part: