2004 INFINITI QX56 engine

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Revision: August 20072004 QX56 On Board Diagnosis Logic ................................... 151
Possible Cause .................................................... 151
DTC Confirmation Procedure ............................... 151
Diagnostic Procedure ........................................... 152
DTC P1759 FRONT BRAKE SOLENOID VALVE
FUNCTION .............................................................. 154
Description ........................................................... 154
CONSULT-II Reference Value .............................. 154
On Board Diagnosis Logic ................................... 154
Possible Cause .................................................... 154
DTC Confirmation Procedure ............................... 154
Diagnostic Procedure ........................................... 155
DTC P1762 DIRECT CLUTCH SOLENOID VALVE . 157
Description ........................................................... 157
CONSULT-II Reference Value .............................. 157
On Board Diagnosis Logic ................................... 157
Possible Cause .................................................... 157
DTC Confirmation Procedure ............................... 157
Diagnostic Procedure ........................................... 158
DTC P1764 DIRECT CLUTCH SOLENOID VALVE
FUNCTION .............................................................. 160
Description ........................................................... 160
CONSULT-II Reference Value .............................. 160
On Board Diagnosis Logic ................................... 160
Possible Cause .................................................... 160
DTC Confirmation Procedure ............................... 160
Diagnostic Procedure ........................................... 161
DTC P1767 HIGH AND LOW REVERSE CLUTCH
SOLENOID VALVE ................................................. 163
Description ........................................................... 163
CONSULT-II Reference Value .............................. 163
On Board Diagnosis Logic ................................... 163
Possible Cause .................................................... 163
DTC Confirmation Procedure ............................... 163
Diagnostic Procedure ........................................... 164
DTC P1769 HIGH AND LOW REVERSE CLUTCH
SOLENOID VALVE FUNCTION ............................. 166
Description ........................................................... 166
CONSULT-II Reference Value .............................. 166
On Board Diagnosis Logic ................................... 166
Possible Cause .................................................... 166
DTC Confirmation Procedure ............................... 166
Diagnostic Procedure ........................................... 167
DTC P1772 LOW COAST BRAKE SOLENOID
VALVE ..................................................................... 169
Description ........................................................... 169
CONSULT-II Reference Value .............................. 169
On Board Diagnosis Logic ................................... 169
Possible Cause .................................................... 169
DTC Confirmation Procedure ............................... 169
Diagnostic Procedure ........................................... 170
DTC P1774 LOW COAST BRAKE SOLENOID
VALVE FUNCTION ................................................. 172
Description ........................................................... 172
CONSULT-II Reference Value .............................. 172
On Board Diagnosis Logic ................................... 172
Possible Cause .................................................... 172
DTC Confirmation Procedure ............................... 172
Diagnostic Procedure ........................................... 173DTC P1841 ATF PRESSURE SWITCH 1 ...............175
Description ............................................................175
CONSULT-II Reference Value ..............................175
On Board Diagnosis Logic ....................................175
Possible Cause .....................................................175
DTC Confirmation Procedure ...............................175
Diagnostic Procedure ...........................................176
DTC P1843 ATF PRESSURE SWITCH 3 ...............178
Description ............................................................178
CONSULT-II Reference Value ..............................178
On Board Diagnosis Logic ....................................178
Possible Cause .....................................................178
DTC Confirmation Procedure ...............................178
Diagnostic Procedure ...........................................179
DTC P1845 ATF PRESSURE SWITCH 5 ...............181
Description ............................................................181
CONSULT-II Reference Value ..............................181
On Board Diagnosis Logic ....................................181
Possible Cause .....................................................181
DTC Confirmation Procedure ...............................181
Diagnostic Procedure ...........................................182
DTC P1846 ATF PRESSURE SWITCH 6 ...............184
Description ............................................................184
CONSULT-II Reference Value ..............................184
On Board Diagnosis Logic ....................................184
Possible Cause .....................................................184
DTC Confirmation Procedure ...............................184
Diagnostic Procedure ...........................................185
CLOSED THROTTLE POSITION AND WIDE OPEN
THROTTLE POSITION CIRCUIT ............................187
CONSULT-II Reference Value ..............................187
Diagnostic Procedure ...........................................187
BRAKE SIGNAL CIRCUIT ......................................188
CONSULT-II Reference Value ..............................188
Diagnostic Procedure ...........................................188
TOW MODE SWITCH .............................................189
Description ............................................................189
Diagnostic Procedure ...........................................189
TROUBLE DIAGNOSIS FOR SYMPTOMS ............191
AT CHECK Indicator Lamp Does Not Come On ..191
Engine Cannot Be Started In “P” or “N” Position ..192
In “P” Position, Vehicle Moves When Pushed ......193
In “N” Position, Vehicle Moves ..............................194
Large Shock (“N” to “D” Position) .........................195
Vehicle Does Not Creep Backward In “R” Position .198
Vehicle Does Not Creep Forward In “D” Position . 201
Vehicle Cannot Be Started From D
1 .....................203
A/T Does Not Shift: D
1 → D2 ................................206
A/T Does Not Shift: D
2 → D3 ................................208
A/T Does Not Shift: D
3 → D4 ................................210
A/T Does Not Shift: D
4 → D5 ................................213
A/T Does Not Perform Lock-up ............................215
A/T Does Not Hold Lock-up Condition ..................217
Lock-up Is Not Released ......................................219
Engine Speed Does Not Return to Idle ................220
A/T Does Not Shift: 5th gear → 4th gear ..............221
A/T Does Not Shift: 4th gear → 3rd gear ..............224
A/T Does Not Shift: 3rd gear → 2nd gear .............225

AT-4Revision: August 20072004 QX56 A/T Does Not Shift: 2nd gear → 1st gear .............227
Vehicle Does Not Decelerate By Engine Brake ....230
SHIFT CONTROL SYSTEM ....................................233
Control Device Removal and Installation ..............233
Adjustment of A/T Position ...................................234
Checking of A/T Position ......................................234
A/T SHIFT LOCK SYSTEM .....................................236
Description ............................................................236
Shift Lock System Electrical Parts Location .........236
Wiring Diagram — A/T — SHIFT ..........................237
Shift Lock Control Unit Reference Values .............238
Component Inspection ..........................................239
ON-VEHICLE SERVICE ..........................................241
Control Valve With TCM and A/T Fluid Temperature
Sensor 2 ...............................................................241
Rear Oil Seal ........................................................252
AIR BREATHER HOSE ...........................................253
Removal and Installation ......................................253
TRANSMISSION ASSEMBLY ................................255
Removal and Installation (4x2) .............................255
Removal and Installation (4x4) .............................258
OVERHAUL .............................................................261
Components .........................................................261
Oil Channel ...........................................................269
Locations of Adjusting Shims, Needle Bearings,
Thrust Washers and Snap Rings ..........................271
DISASSEMBLY .......................................................273
Disassembly .........................................................273REPAIR FOR COMPONENT PARTS ...................... 290
Oil Pump ............................................................... 290
Front Sun Gear, 3rd One-Way Clutch ................... 292
Front Carrier, Input Clutch, Rear Internal Gear ..... 295
Mid Sun Gear, Rear Sun Gear, High and Low
Reverse Clutch Hub .............................................. 300
High and Low Reverse Clutch .............................. 305
Direct Clutch ......................................................... 307
ASSEMBLY ............................................................. 309
Assembly (1) ......................................................... 309
Adjustment ............................................................ 322
Assembly (2) ......................................................... 324
SERVICE DATA AND SPECIFICATIONS (SDS) .... 331
General Specifications .......................................... 331
Vehicle Speed When Shifting Gears ..................... 331
Vehicle Speed When Performing and Releasing
Complete Lock-up ................................................. 332
Vehicle Speed When Performing and Releasing
Slip Lock-up .......................................................... 332
Stall Speed ............................................................ 332
Line Pressure ........................................................ 332
A/T Fluid Temperature Sensor .............................. 332
Turbine Revolution Sensor .................................... 332
Vehicle Speed Sensor A/T (Revolution Sensor) ... 332
Reverse brake ....................................................... 333
Total End Play ....................................................... 333

INDEX FOR DTC
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Revision: August 20072004 QX56
INDEX FOR DTCPFP:00024
Alphabetical Index UCS002BZ
NOTE:
If DTC U1000 is displayed with other DTC, first perform the trouble diagnosis for DTC U1000. Refer to
AT-1 03
.
*1: These numbers are prescribed by SAE J2012.
*2: These malfunctions cannot be displayed MIL if another malfunction is assigned to MIL.Items
(CONSULT- II screen terms) DTC
Reference page OBD- II Except OBD- II
CONSULT- II GST (*1) CONSULT- II only “A/T”
A/T 1ST E/BRAKING — P1731AT- 1 4 2
ATF PRES SW 1/CIRC — P1841AT- 1 7 5
ATF PRES SW 3/CIRC — P1843AT- 1 7 8
ATF PRES SW 5/CIRC — P1845AT- 1 8 1
ATF PRES SW 6/CIRC — P1846AT- 1 8 4
A/T INTERLOCK P1730 P1730AT- 1 3 9
A/T TCC S/V FNCTN P0744 P0744 AT- 1 2 1
ATF TEMP SEN/CIRC P0710 P1710AT- 1 3 1
CAN COMM CIRCUIT U1000 U1000AT- 1 0 3
D/C SOLENOID/CIRC P1762 P1762AT- 1 5 7
D/C SOLENOID FNCTN P1764 (*2 ) P1764 AT- 1 6 0
ENGINE SPEED SIG — P0725AT- 11 5
FR/B SOLENOID/CIRC P1757 P1757AT- 1 5 1
FR/B SOLENOID FNCT P1759 P1759 AT- 1 5 4
HLR/C SOL/CIRC P1767 P1767AT- 1 6 3
HLR/C SOL FNCTN P1769 (*2 ) P1769 AT- 1 6 6
I/C SOLENOID/CIRC P1752 P1752AT- 1 4 5
I/C SOLENOID FNCTN P1754 (*2 ) P1754 AT- 1 4 8
L/PRESS SOL/CIRC P0745 P0745AT- 1 2 4
LC/B SOLENOID/CIRC P1772 P1772AT- 1 6 9
LC/B SOLENOID FNCT P1774 P1774 AT- 1 7 2
PNP SW/CIRC P0705 P0705AT- 1 0 9
STARTER RELAY/CIRC — P0615AT- 1 0 5
TCC SOLENOID/CIRC P0740 P0740AT- 11 8
TCM P0700 P0700AT- 1 0 8
TCM·RAM — P1702AT- 1 2 7
TCM·ROM — P1703AT- 1 2 8
TP SEN/CIRC A/T — P1705AT- 1 2 9
TURBINE REV S/CIRC P1716 P1716AT- 1 3 4
VEH SPD SE/CIR·MTR — P1721AT- 1 3 6
VEH SPD SEN/CIR AT P0720 P0720AT- 11 2

AT-6
INDEX FOR DTC
Revision: August 20072004 QX56
DTC No. Index UCS002C0
NOTE:
If DTC U1000 is displayed with other DTC, first perform the trouble diagnosis for DTC U1000. Refer to
AT- 1 0 3 , "
DTC U1000 CAN COMMUNICATION LINE" .
*1: These numbers are prescribed by SAE J2012.
*2: These malfunctions cannot be displayed MIL if another malfunction is assigned to MIL.DTC
Items
(CONSULT- II screen terms)Reference page OBD- II Except OBD- II
CONSULT- II
GST (*1)C O N S U LT- I I
only “A/T”
— P0615 STARTER RELAY/CIRCAT- 1 0 5
P0700 P0700 TCMAT- 1 0 8
P0705 P0705 PNP SW/CIRCAT- 1 0 9
P0710 P1710 ATF TEMP SEN/CIRCAT- 1 3 1
P0720 P0720 VEH SPD SEN/CIR ATAT-11 2
— P0725 ENGINE SPEED SIGAT-11 5
P0740 P0740 TCC SOLENOID/CIRCAT-11 8
P0744 P0744 A/T TCC S/V FNCTNAT- 1 2 1
P0745 P0745 L/PRESS SOL/CIRCAT- 1 2 4
— P1702 TCM·RAMAT- 1 2 7
— P1703 TCM·ROMAT- 1 2 8
— P1705 TP SEN/CIRC A/TAT- 1 2 9
P1716 P1716 TURBINE REV S/CIRCAT- 1 3 6
— P1721 VEH SPD SE/CIR·MTRAT- 1 3 6
P1730 P1730 A/T INTERLOCKAT- 1 3 9
— P1731 A/T 1ST E/BRAKINGAT- 1 4 2
P1752 P1752 I/C SOLENOID/CIRCAT- 1 4 5
P1754 (*2 ) P1754 I/C SOLENOID FNCTNAT- 1 4 8
P1757 P1757 FR/B SOLENOID/CIRCAT- 1 5 1
P1759 (*2 ) P1759 FR/B SOLENOID FNCTAT- 1 5 4
P1762 P1762 D/C SOLENOID/CIRCAT- 1 5 7
P1764 (*2 ) P1764 D/C SOLENOID FNCTNAT- 1 6 0
P1767 P1767 HLR/C SOL/CIRCAT- 1 6 3
P1769 P1769 HLR/C SOL FNCTNAT- 1 6 6
P1772 P1772 LC/B SOLENOID/CIRCAT- 1 6 9
P1774 P1774 LC/B SOLENOID FNCTAT- 1 7 2
— P1841 ATF PRES SW 1/CIRCAT- 1 7 5
— P1843 ATF PRES SW 3/CIRCAT- 1 7 8
— P1845 ATF PRES SW 5/CIRCAT- 1 8 1
— P1846 ATF PRES SW 6/CIRCAT- 1 8 4
U1000 U1000 CAN COMM CIRCUITAT- 1 0 3

PRECAUTIONS
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Revision: August 20072004 QX56
PRECAUTIONSPFP:00001
Precautions for Supplemental Restraint System (SRS) “AIR BAG” and “SEAT
BELT PRE-TENSIONER”
UCS002C1
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 On Board Diagnostic (OBD) System of A/T and EngineUCS002C2
The ECM has an on board diagnostic system. It will light up the malfunction indicator lamp (MIL) to warn the
driver of a malfunction causing emission deterioration.
CAUTION:

Be sure to turn the ignition switch “OFF” and disconnect the negative battery cable before any
repair or inspection work. The open/short circuit of related switches, sensors, solenoid valves,
etc. Will cause the MIL to light up.

Be sure to connect and lock the connectors securely after work. A loose (unlocked) connector will
cause the MIL to light up due to an open circuit. (Be sure the connector is free from water, grease,
dirt, bent terminals, etc.)

Be sure to route and secure the harnesses properly after work. Interference of the harness with a
bracket, etc. May cause the MIL to light up due to a short circuit.

Be sure to connect rubber tubes properly after work. A misconnected or disconnected rubber tube
may cause the MIL to light up due to a malfunction of the EGR system or fuel injection system, etc.

Be sure to erase the unnecessary malfunction information (repairs completed) from the TCM and
ECM before returning the vehicle to the customer.

A/T FLUID
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Revision: August 20072004 QX56
A/T FLUIDPFP:KLE40
Changing A/T FluidUCS002C8
1. Increase ATF temperature by 80°C (176°F) once.
2. Stop engine.
3. Remove the tightening bolt for 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 Genuine NISSAN ATF Matic Fluid J. Do not mix with other fluid.

Using automatic transmission fluid other than Genuine NISSAN ATF Matic Fluid J will cause
deterioration in driveability and automatic transmission durability, and may damage the auto-
matic transmission, which is not covered by the warranty.

When filling ATF, take care not to scatter heat generating parts such as exhaust.
5. Increase ATF temperature by 80°C (176°F) once.
6. Check fluid level and condition. Refer to AT-13, "
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.
Checking A/T FluidUCS002C9
1. Warm up engine.
2. Check for fluid leakage.
3. Remove the tightening bolt for ATF level gauge.
4. Before driving, fluid level can be checked at fluid temperatures of 30° to 50°C (86° to 122°F) using
“COLD” range on ATF level gauge as follows.
a. Park vehicle on level surface and set parking brake.
b. Start engine and move selector lever through each gear position. Leave selector lever in “P” position.
c. Check fluid level with engine idling.
d. Remove ATF level gauge and wipe clean with lint-free paper.
CAUTION:
When wiping away the fluid level gauge, always use lint-free paper, not a cloth one.
e. Re-insert ATF level gauge into charging pipe as far as it will go.
CAUTION:
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.
f. Remove ATF level gauge and note reading. If reading is at low side of range, add fluid to the charging
pipe.
CAUTION:
Do not overfill.
5. Increase ATF temperature by 80°C (176°F) once. ATF: NISSAN Matic Fluid J
Fluid capacity: 10.6 (11-1/4 US qt, 9-3/8 lmp qt)
Drain plug:
: 34 N·m (3.5 kg-m, 25 ft-lb)
Level gauge bolt:
: 5.1 N·m (0.52 kg-m, 45 in-lb)

A/T CONTROL SYSTEM
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Revision: August 20072004 QX56
“D”, “4”, “3”, “2” Positions 1st Gear

The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.

The 1st one-way clutch regulates reverse rotation of the rear sun gear.

The 3rd one-way clutch regulates reverse rotation of the front sun gear.

During deceleration, the mid sun gear turns forward, so the forward one-way clutch idles and the engine
brake is not activated.
1. Front brake 2. Input clutch 3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear 12. Input shaft
13. Mid internal gear 14. Front internal gear 15. Rear carrier
16. Rear sun gear 17. Mid sun gear 18. Front carrier
19. Mid carrier 20. Rear internal gear 21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1512E

AT-24
A/T CONTROL SYSTEM
Revision: August 20072004 QX56
“1 ” Position 1st Gear

The front brake fastens the front sun gear.

The forward brake and the forward one-way clutch regulate reverse rotation of the mid sun gear.

High and low reverse clutch connects the rear sun gear and the mid sun gear.

The low coast brake fastens the mid sun gear.

During deceleration, the low coast brake regulates forward rotation of the mid sun gear and the engine
brake functions.
1. Front brake 2. Input clutch 3. Direct clutch
4. High and low reverse clutch 5. Reverse brake 6. Forward brake
7. Low coast brake 8. 1st one-way clutch 9. Forward one-way clutch
10. 3rd one-way clutch 11. Front sun gear 12. Input shaft
13. Mid internal gear 14. Front internal gear 15. Rear carrier
16. Rear sun gear 17. Mid sun gear 18. Front carrier
19. Mid carrier 20. Rear internal gear 21. Output shaft
22. Parking gear 23. Parking pawl
SCIA1513E