2004 INFINITI QX56 check engine

TROUBLE DIAGNOSIS FOR SYMPTOMS
AT-219
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Revision: August 20072004 QX56
7. DETECT MALFUNCTIONING ITEM

Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.25).
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
Lock-up Is Not ReleasedUCS002IW
SYMPTOM:
The lock-up condition cannot be cancelled even after releasing the accelerator pedal.
DIAGNOSTIC PROCEDURE
1. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 3 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate torque converter clutch solenoid valve, engine speed signal, turbine rev-
olution sensor, CAN communication?
YES >> Check the malfunctioning system. Refer to AT- 11 8 , "DTC P0740 TORQUE CONVERTER
CLUTCH SOLENOID VALVE" , AT-115, "DTC P0725 ENGINE SPEED SIGNAL" , AT- 1 3 4 , "DTC
P1716 TURBINE REVOLUTION SENSOR" , AT-103, "DTC U1000 CAN COMMUNICATION
LINE" .
NO >> GO TO 2.
2. CHECK SYMPTOM
Check again. Refer to AT- 6 3 , "
Cruise Test - Part 1" .
OK or NG
OK >>INSPECTION END
NG >> GO TO 3.
3. PERFORM TCM INSPECTION
1. Perform TCM input/output signals inspection. Refer to AT-90, "
TCM Input/Output Signal Reference Val-
ues" .
2. If NG, recheck A/T assembly harness connector terminals for damage or loose connection with harness
connector.
OK or NG
OK >>INSPECTION END
NG >> Repair or replace damaged parts.

AT-220
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
Engine Speed Does Not Return to IdleUCS002IX
SYMPTOM:
When a shift-down is performed, the engine speed does not smoothly return to the idling speed.
DIAGNOSTIC PROCEDURE
1. CHECK A/T FLUID LEVEL
Check A/T fluid level. Refer to AT-13, "
Checking A/T Fluid" .
OK or NG
OK >> GO TO 2.
NG >> Refill ATF.
2. CHECK SELF-DIAGNOSTIC RESULTS
Perform self-diagnosis. Refer to AT- 9 3 , "
SELF-DIAGNOSTIC RESULT MODE" .
Do the self-diagnostic results indicate front brake solenoid valve, direct clutch solenoid valve, ATF pressure
switch 1, ATF pressure switch 5, accelerator pedal position sensor, vehicle speed sensor A/T (revolution sen-
sor) and vehicle speed sensor MTR?
YES >> Check the malfunctioning system. Refer to AT-151, "DTC P1757 FRONT BRAKE SOLENOID
VA LV E" , AT-157, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE" , AT- 1 7 5 , "DTC P1841
ATF PRESSURE SWITCH 1" , AT-181, "DTC P1845 ATF PRESSURE SWITCH 5" , AT-129,
"DTC P1705 THROTTLE POSITION SENSOR" , AT- 11 2 , "DTC P0720 VEHICLE SPEED SEN-
SOR A/T (REVOLUTION SENSOR)" , AT-136, "DTC P1721 VEHICLE SPEED SENSOR MTR" .
NO >> GO TO 3.
3. CHECK A/T FLUID CONDITION
1. Remove oil pan. Refer to AT-241, "
Control Valve With TCM and A/T Fluid Temperature Sensor 2" .
2. Check A/T fluid condition. Refer to AT- 5 8 , "
Fluid Condition
Check" .
OK or NG
OK >> GO TO 4.
NG >> GO TO 7.
4. DETECT MALFUNCTIONING ITEM

Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.65).
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
SAT6 3 8A
SCIA5199E

AT-222
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
2. CHECK 4TH POSITION SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for
"A/T" with CONSULT-II.
3. Read out "OD CONT SW" switch moving selector lever to each
position.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine)
2. Check voltage between A/T device harness connector terminal
and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK A/T FLUID LEVEL
Check the A/T fluid level again. Refer to AT- 1 3 , "
Checking A/T Fluid"
.
OK or NG
OK >> GO TO 4.
NG >> Refill ATF.
Monitor item Condition Display value
OD CONT SWWhen setting the selector
lever to "4" and "3" posi-
tion.ON
When setting selector
lever to other positions.OFF
LCIA0339E
Item Connector No.Te r m i n a l N o .
(Wire color)ConditionData
(Approx.)
4th position
switchM2031 (SB) -
GroundWhen setting
the selector
lever to "4"
and "3" posi-
tion.0V
When setting
selector lever
to other posi-
tions.Battery volt-
age
LCIA0340E
SAT6 3 8A

AT-228
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
2. CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for
"A/T" with CONSULT-II.
3. Read out "1 POSITION SW" switch moving selector lever to
each position.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine)
2. Check voltage between A/T device harness connector terminal
and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3. CHECK A/T FLUID LEVEL
Check the A/T fluid level again. Refer to AT- 1 3 , "
Checking A/T Fluid"
.
OK or NG
OK >> GO TO 4.
NG >> Refill ATF.
Monitor item Condition Display value
1 POSITION SWWhen setting the selector
lever to "1" position.ON
When setting selector
lever to other positions.OFF
LCIA0339E
Item Connector No.Te r m i n a l N o .
(Wire color)ConditionData
(Approx.)
1st position
switchM2037 (Y/G) -
GroundWhen setting
the selector
lever to "1"
position.0V
When setting
selector lever
to other posi-
tions.Battery volt-
age
LCIA0341E
SAT6 3 8A

AT-230
TROUBLE DIAGNOSIS FOR SYMPTOMS
Revision: August 20072004 QX56
9. DETECT MALFUNCTIONING ITEM

Check the malfunction items. If any items are damaged, repair or replace damaged parts. Refer to AT-68,
"Symptom Chart" (Symptom No.17).
OK or NG
OK >> GO TO 7.
NG >> Repair or replace damaged parts.
Vehicle Does Not Decelerate By Engine BrakeUCS002J 2
SYMPTOM:
No engine brake is applied when the gear is shifted from the 22 to 11 .
DIAGNOSTIC PROCEDURE
1. CHECK SELF-DIAGNOSIS RESULTS
Perform self-diagnosis.
Do the self-diagnosis results indicate PNP switch, ATF pressure switch 5?
YES >> Check the malfunctioning system. Refer to AT-109, "DTC P0705 PARK/NEUTRAL POSITION
SWITCH" , AT-181, "DTC P1845 ATF PRESSURE SWITCH 5" .
NO >> GO TO 2.
2. CHECK 1ST POSITION SWITCH CIRCUIT
With CONSULT-II
1. Turn ignition switch “ON”.
2. Select "ECU INPUT SIGNALS" in "DATA MONITOR" mode for
"A/T" with CONSULT-II.
3. Read out "OVERDRIVE SW" switch moving selector lever to
each position.
Without CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine)
2. Check voltage between A/T device harness connector terminal
and ground.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
Monitor item Condition Display value
1 POSITION SWWhen setting the selector
lever to "1" position.ON
When setting selector
lever to other positions.OFF
LCIA0339E
Item Connector No.Te r m i n a l N o .
(Wire color)ConditionData
(Approx.)
1st position
switchM2037 (Y/G) -
GroundWhen setting
the selector
lever to "1"
position.0V
When setting
selector lever
to other posi-
tions.Battery volt-
age
LCIA0341E

AT-234
SHIFT CONTROL SYSTEM
Revision: August 20072004 QX56
REMOVAL
1. Remove the select lever knob.
2. Remove console finisher.

Refer to IP-10, "INSTRUMENT PANEL ASSEMBLY" .
3. Remove center console.

Refer to IP-10, "INSTRUMENT PANEL ASSEMBLY" .
4. Disconnect selector control cable.
5. Disconnect A/T device harness connector.
6. Remove control device assembly.
INSTALLATION
Installation is in reverse order of removal.
NOTE:


: Vehicle front
Apply adhesive, Cemedyne 3000 or equivalent, to thread of select
lever knob before installation. Rotate knob clockwise through com-
plete thread range (A) at low torque. When knob rotation is finished
through complete thread range, rotation torque will sunddenly
increase. Continue knob rotation in incomplete thread range (B), not
more than 360°, until knob rotational position is as shown.

After installation is completed, adjust and check A/T position.
Adjustment of A/T PositionECS0090O
1. Loosen nut of control cable.
2. Place PNP switch and selector lever in “P” position.
3. After pushing the control cable in the direction shown with a
force of 9.8 N·m (1kg-m, 2.2 lb-ft), release it. This is in the natu-
ral state, tighten control cable nut to specifications.
Checking of A/T PositionECS0090P
1. Place selector lever in “P” position, and turn ignition switch ON
(engine stop).
2. Make sure selector lever can be shifted to other than “P” posi-
tion when brake pedal is depressed. Also make sure selector
lever can be shifted from “P” position only when brake pedal is
depressed.
3. Move the selector lever and check for excessive effort, sticking,
noise or rattle.
4. Confirm the selector lever stops at each position with the feel of
engagement when it is moved through all the positions. Check
whether or not the actual position the selector lever is in
matches the position shown by the shift position indicator and
the transmission body.
5. The method of operating the lever to individual positions correctly should be as shown.
6. Confirm the back-up lamps illuminate only when lever is placed in the “R” position. Confirm the back-up
lamps does not illuminate when selector lever is pushed against “R” position in the “P” or “N” position.
LCIA0323E
LCIA0397E
Control cable nut : 14.5 N·m (1.5 kg-m, 11 ft-lb)
LCIA0345E
LCIA0325E

AT-256
TRANSMISSION ASSEMBLY
Revision: August 20072004 QX56
8. Remove crankshaft position sensor (POS) from A/T assembly.
9. Remove fluid cooler tube.
10. Remove dust cover from converter housing part.
11. Turn crankshaft, and remove the four tightening bolts for drive
plate and torque converter.
CAUTION:
When turning crankshaft, turn it clockwise as viewed from
the front of the engine.
12. Support A/T assembly with a transmission jack.
CAUTION:
When setting the transmission jack, be careful not to allow
it to collide against the drain plug.
13. Remove cross member with power tool.
14. Remove air breather hose. Refer to AT-253, "
Removal and
Installation" .
15. Disconnect A/T assembly connector.
16. Remove A/T fluid indicator pipe from A/T assembly.
17. Plug up openings such as the fluid charging pipe hole, etc.
18. Remove the A/T assembly to engine bolts with power tool.
19. Remove A/T assembly from vehicle using Tool and a transmis-
sion jack.

Secure torque converter to prevent it from dropping.

Secure A/T assembly to a transmission jack.
INSPECTION
Installation and Inspection of Torque Converter

After inserting a torque converter to a transmission, be sure to
check dimension A to ensure it is within the reference value
limit.
LCIA0334E
Tool number : — (J-47002)
LCIA0335E
SCIA0499E
Dimension A : 24.0 mm (0.94 in) or more
SAT0 1 7B

TRANSMISSION ASSEMBLY
AT-257
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Revision: August 20072004 QX56
INSTALLATION
Installation of the remaining components is in the reverse order of
the removal, while paying attention to the following work.

If removed install drive plate.
–Align dowel pin of crankshaft rear end with pin holes of each
parts to install.
–Install drive plate, reinforcement plate and pilot converter as
shown.
–Face chamfered or rounded edge side to crankshaft.
CAUTION:

When replacing an engine or transmission you must make
sure the dowels are installed correctly during re-assembly.

Improper alignment caused by missing dowels may cause
vibration, oil leaks or breakage of drivetrain components.

When installing transmission to the engine, attach the bolts in
accordance with the following standard.
*: No.2 bolt also secures air breather vent.
–Align the positions of tightening bolts for drive plate with those of
the torque converter, and temporarily tighten the bolts. Then,
tighten the bolts with the specified torque.
CAUTION:

When turning crankshaft, turn it clockwise as viewed from the front of the engine.

After converter is installed to drive plate, rotate crankshaft several turns and check to be sure that
transmission rotates freely without binding.

After completing installation, check fluid leakage, fluid level, and the positions of A/T. Refer to AT-13,
"Checking A/T Fluid" , AT-234, "Checking of A/T Position" , AT-234, "Adjustment of A/T Position" .
KBIA2494E
KBIA2537E
Bolt No. 1 2* 3
Number of bolts 4 1 4
Bolt length
“”mm (in)70 (2.76) 70 (2.76) 70 (2.76)
Tightening torque
N·m (kg-m, ft-lb)11 3
(12, 83)11 3
(12, 83)
LCIA0371E
LCIA0335E