2007 INFINITI QX56 clutch

TROUBLE DIAGNOSIS
AT-79
< SERVICE INFORMATION >
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P53
OthersVehicle dose not de-
celerate by engine
brake.
Refer to AT- 1 9 9 , "Ve -
hicle Does Not Decel-
erate By Engine
Brake".ON vehicle1. PNP switchAT- 9 9
2. Fluid level and stateAT- 5 1
3. Control cable adjustmentAT-208
4. 1st position switchAT-199
5. ATF pressure switch 5AT-154
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT-210
OFF vehicle8. Input clutchAT-2629. High and low reverse clutchAT-272
10. Direct clutchAT-274
54Engine brake does not
operate in “2” position.ON vehicle1. PNP switchAT- 9 9
2. Fluid level and stateAT- 5 1
3. Control cable adjustmentAT-208
5. ATF pressure switch 6AT-156
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT-210
OFF vehicle8. Front brake (brake band)AT-2409. Input clutchAT-262
10. High and low reverse clutchAT-272
55Engine brake does not
operate in “1” position.ON vehicle1. PNP switchAT- 9 9
2. Fluid level and stateAT- 5 1
3. Control cable adjustmentAT-208
4. 1st position switchAT-199
5. ATF pressure switch 5AT-154
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT-210
OFF vehicle8. Input clutchAT-2629. High and low reverse clutchAT-272
10. Direct clutchAT-274
No. Items Symptom Condition Diagnostic ItemReference
page

AT-80
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
56
OthersMaximum speed low.ON vehicle1. Fluid level and stateAT- 5 1
2. Line pressure testAT- 5 1
3. Accelerator pedal position sensorAT- 11 7
4. CAN communication lineAT- 9 1
5. Direct clutch solenoid valveAT- 1 3 8
6. Control valve with TCMAT- 2 1 0
OFF vehicle7. Torque converterAT- 2 4 0
8. Oil pump assemblyAT- 2 5 8
9. Input clutchAT- 2 6 2
10. Gear systemAT- 2 2 8
11. High and low reverse clutchAT- 2 7 2
12. Direct clutchAT- 2 7 4
13. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to AT-
19, AT- 2 0.)AT- 2 4 0
14 Forward brake (Parts behind drum support is impossible to
perform inspection by disassembly. Refer to AT- 1 9
, AT- 2 0.)AT- 2 4 0
57 Extremely large creep.ON vehicle1. Engine idle speed EC-75

2. CAN communication lineAT- 9 1
3. ATF pressure switch 5AT- 1 5 4
OFF vehicle 4. Torque converterAT- 2 4 0
58With selector lever in
“P” position, vehicle
does not enter parking
condition or, with se-
lector lever in another
position, parking con-
dition is not cancelled.
Refer to AT-168, "
In
"P" Position, Vehicle
Moves When
Pushed".ON vehicle1. PNP switchAT- 9 9
2. Control cable adjustmentAT- 2 0 8
OFF vehicle 3. Parking pawl componentsAT- 2 2 8
59Vehicle runs with
transmission in “P” po-
sition.ON vehicle1. PNP switchAT- 9 9
2. Fluid level and stateAT- 5 1
3. Control cable adjustmentAT- 2 0 8
4. Control valve with TCMAT- 2 1 0
5. Parking pawl componentsAT- 2 2 8
OFF vehicle 6. Gear systemAT- 2 2 8
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-81
< SERVICE INFORMATION >
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60
OthersVehicle runs with
transmission in “N” po-
sition.
Refer to AT- 1 6 9 , "In
"N" Position, Vehicle
Moves".ON vehicle1. PNP switchAT- 9 9
2. Fluid level and stateAT- 5 1
3. Control cable adjustmentAT-208
4. Control valve with TCMAT-210
OFF vehicle5. Input clutchAT-262
6. Gear systemAT-228
7. Direct clutchAT-274
8. Reverse brakeAT-240
9. Forward one- way clutch (Parts behind drum support is im-
possible to perform inspection by disassembly. Refer to AT-
19, AT- 2 0.)AT-240
10. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 9
, AT- 2 0.)AT-240
61Engine does not start
in “N” or “P” position.
Refer to AT- 1 6 8 , "En-
gine Cannot Be Start-
ed in "P" or "N"
Position".ON vehicle1. Ignition switch and starterPG-3
, SC-
9
2. Control cable adjustmentAT-208
3. PNP switchAT- 9 9
62Engine starts in posi-
tions other than “N” or
“P”.ON vehicle1. Ignition switch and starterPG-3
, SC-
9
2. Control cable adjustmentAT-208
3. PNP switchAT- 9 9
63 Engine stall.ON vehicle1. Fluid level and stateAT- 5 1
2. Engine speed signalAT-109
3. Turbine revolution sensorAT-103
4. Torque converter clutch solenoid valveAT- 111
5. CAN communication lineAT- 9 1
6. Control valve with TCMAT-210
OFF vehicle 7. Torque converterAT-240
64Engine stalls when se-
lect lever shifted “N” →
“D”, “R”.ON vehicle1. Fluid level and stateAT- 5 1
2. Engine speed signalAT-109
3. Turbine revolution sensorAT-103
4. Torque converter clutch solenoid valveAT- 111
5. CAN communication lineAT- 9 1
6. Control valve with TCMAT-210
OFF vehicle 7. Torque converterAT-240
No. Items Symptom Condition Diagnostic ItemReference
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AT-82
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
TCM Input/Output Signal Reference Value
INFOID:0000000003532258
A/T ASSEMBLY HARNESS CONNECTOR TERMINAL LAYOUT
TERMINAL AND REFERENCE VALUES FOR TCM
Data are reference value and are measured between each terminal and ground.
65 OthersEngine speed does
not return to idle.
Refer to AT-191, "En-
gine Speed Does Not
Return to Idle".ON vehicle1. Fluid level and stateAT- 5 1
2. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT- 1 3 8
3. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 0,
AT- 1 3 4
4. Accelerator pedal position sensorAT- 11 7
5. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT- 1 2 4
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT- 2 1 0
OFF vehicle8. Front brake (brake band)AT- 2 4 09. Direct clutchAT- 2 7 4
No. Items Symptom Condition Diagnostic ItemReference
page
SCIA1658E
Te r m i n a l
No.Wire
colorItem Condition Data (Pyrex.)
1PPower supply
(Memory back-up)Always Battery voltage
2PPower supply
(Memory back-up)Always Battery voltage
3 L CAN-H – –
4VK-line (CONSULT-
II signal)The terminal is connected to the data link connector for CONSULT-II. –
5 B Ground Always 0V
6Y/RPower supply– Battery voltage
–0V
7RBack-up lamp re-
laySelector lever in “R” position. 0V
Selector lever in other positions. Battery voltage
8 P CAN-L – –

AT-84
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
CONSULT-II START PROCEDURE
Refer to GI-36, "CONSULT-II Start Procedure".
SELF-DIAGNOSTIC RESULT MODE
Operation Procedure
After performing SELF-DIAGNOSTIC RESULT MODE, place check marks for results on the AT-44, "How To
Perform Trouble Diagnosis for Quick and Accurate Repair". Reference pages are provided following the items.
Display Items List
LINE PRES SOL During driving 0.2 - 0.6 A
TURBINE REV During driving (lock-up ON)Approximately matches the en-
gine speed.
VHCL/S SE·MTR During drivingApproximately matches the
speedometer reading.
ATF PRES SW 1Front brake engaged. Refer to AT- 2 0
ON
Front brake disengaged. Refer to AT- 2 0
OFF
ATF PRES SW 2Low coast brake engaged. Refer to AT- 2 0
ON
Low coast brake disengaged. Refer to AT- 2 0
OFF
ATF PRES SW 3Input clutch engaged. Refer to AT- 2 0
ON
Input clutch disengaged. Refer to AT- 2 0
OFF
ATF PRES SW 5Direct clutch engaged. Refer to AT- 2 0
ON
Direct clutch disengaged. Refer to AT- 2 0
OFF
ATF PRES SW 6High and low reverse clutch engaged. Refer to AT- 2 0
ON
High and low reverse clutch disengaged. Refer to AT- 2 0
OFF
I/C SOLENOIDInput clutch disengaged. Refer to AT- 2 0
0.6 - 0.8 A
Input clutch engaged. Refer to AT- 2 0
0 - 0.05 A
FR/B SOLENOIDFront brake engaged. Refer to AT- 2 0
0.6 - 0.8 A
Front brake disengaged. Refer to AT- 2 0
0 - 0.05 A
D/C SOLENOIDDirect clutch disengaged. Refer to AT- 2 0
0.6 - 0.8 A
Direct clutch engaged. Refer to AT- 2 0
0 - 0.05 A
HLR/C SOLHigh and low reverse clutch disengaged. Refer to AT- 2 0
0.6 - 0.8 A
High and low reverse clutch engaged. Refer to AT- 2 0
0 - 0.05 A
ON OFF SOLLow coast brake engaged. Refer to AT- 2 0
ON
Low coast brake disengaged. Refer to AT- 2 0
OFF
STARTER RELAYSelector lever in “N”,“P” position. ON
Selector lever in other position. OFF
ACCELE POSIReleased accelerator pedal. 0.0/8
Fully depressed accelerator pedal. 8/8
CLSD THL POSReleased accelerator pedal. ON
Fully depressed accelerator pedal. OFF
W/O THL POSFully depressed accelerator pedal. ON
Released accelerator pedal. OFF
BRAKE SWDepressed brake pedal. ON
Released brake pedal. OFF Item name Condition Display value (Approx.)

DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE
AT-111
< SERVICE INFORMATION >
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DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE
DescriptionINFOID:0000000003532304
• The torque converter clutch solenoid valve is activated, with the gear in D4, D5 by the TCM in response to
signals sent from the vehicle speed sensor and accelerator pedal position sensor (throttle position sensor).
Torque converter clutch piston operation will then be controlled.
• Lock-up operation, however, is prohibited when A/T fluid temperature is too low.
• When the accelerator pedal is depressed (less than 1/8) in lock-up condition, the engine speed should not
change abruptly. If there is a big jump in engine speed, there is no lock-up.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532305
On Board Diagnosis LogicINFOID:0000000003532306
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P0740 TCC SOLENOID/CIRC” with CONSULT-II is detected under the following
conditions.
- When TCM detects an improper voltage drop when it tries to operate the solenoid valve.
- When TCM detects as irregular by comparing target value with monitor value.
Possible CauseINFOID:0000000003532307
• Torque converter clutch solenoid valve
• Harness or connectors
(The solenoid circuit is open or shorted.)
DTC Confirmation ProcedureINFOID:0000000003532308
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Turn ignition switch “ON”. (Do not start engine.)
2. Select “DATA MONITOR” mode for “ENGINE” with CONSULT-II.
3. Start engine and maintain the following conditions for at least 5
consecutive seconds.
VHCL SPEED SE: 80 km/h (50 MPH) or more
ACCELE POS: 0.5/8 - 1.0/8
SELECTOR LEVER: “D” position
Driving location: Driving the vehicle uphill (increased
engine load) will help maintain the driving conditions
required for this test.
4. If DTC is detected go to AT- 111 , "
Diagnosis Procedure".
WITH GST
Follow the procedure “With CONSULT-II”.
Diagnosis ProcedureINFOID:0000000003532309
1.CHECK INPUT SIGNAL
With CONSULT-II
Item name Condition Display value (Approx.)
TCC SOLENOIDWhen performing slip lock-up 0.2 - 0.4 A
When performing lock-up 0.4 - 0.6 A
BCIA0031E

AT-112
< SERVICE INFORMATION >
DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE
1. Turn ignition switch “ON”.
2. Select “MAIN SIGNALS” in “DATA MONITOR” mode for “A/T”
with CONSULT-II.
3. Start engine.
4. Read out the value of “TCC SOLENOID” while driving.
OK or NG
OK >> GO TO 4.
NG >> GO TO 2.
2.CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to AT-158
.
OK or NG
OK >> GO TO 3.
NG >> Repair or replace damaged parts.
3.DETECT MALFUNCTIONING ITEM
Check the following items:
• The A/T assembly harness connector pin terminals for damage or loose connection with harness connector.
OK or NG
OK >> Replace the control valve with TCM. Refer to AT-210, "Control Valve with TCM and A/T Fluid Tem-
perature Sensor 2".
NG >> Repair or replace damaged parts.
4.CHECK DTC
Perform “DTC Confirmation Procedure”.
• Refer to AT- 111 , "
DTC Confirmation Procedure".
OK or NG
OK >>INSPECTION END
NG >> GO TO 2.
Item name Condition Display value (Approx.)
TCC SOLENOIDWhen performing slip lock-up 0.2 - 0.4 A
When performing lock-up 0.4 - 0.6 A
SCIA4793E

DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)
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< SERVICE INFORMATION >
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DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)
DescriptionINFOID:0000000003532310
This malfunction is detected when the A/T does not shift into 5th gear position or the torque converter clutch
does not lock-up as instructed by the TCM. This is not only caused by electrical malfunction (circuits open or
shorted) but also by mechanical malfunction such as control valve sticking, improper solenoid valve operation,
etc.
CONSULT-II Reference Value in Data Monitor ModeINFOID:0000000003532311
On Board Diagnosis LogicINFOID:0000000003532312
• This is an OBD-II self-diagnostic item.
• Diagnostic trouble code “P0744 A/T TCC S/V FNCTN” with CONSULT-II is detected under the following con-
ditions.
- When A/T cannot perform lock-up even if electrical circuit is good.
- When TCM detects as irregular by comparing difference value with slip rotation.
Possible CauseINFOID:0000000003532313
• Harness or connectors
(The solenoid circuit is open or shorted.)
• Torque converter clutch solenoid valve
• Hydraulic control circuit
DTC Confirmation ProcedureINFOID:0000000003532314
CAUTION:
Always drive vehicle at a safe speed.
NOTE:
If “DTC Confirmation Procedure” has been previously performed, always turn ignition switch “OFF”
and wait at least 10 seconds before performing the next test.
After the repair, perform the following procedure to confirm the malfunction is eliminated.
WITH CONSULT-II
1. Start engine and Select “TCC S/V FNCTN CHECK” of “DTC
WORK SUPPORT” mode for “A/T” with CONSULT-II and touch
“START”.
2. Accelerate vehicle to more than 80 km/h (50 MPH) and maintain
the following condition continuously until “TESTING” has turned
to “COMPLETE”. (It will take approximately 30 seconds after
“TESTING” shows.)
ACCELE POSI: More than 1.0/8 (at all times during step 4)
TCC SOLENOID: 0.4 - 0.6 A
Selector lever: “D” position
[Reference speed: Constant speed of more than 80 km/h (50
MPH)]
-Make sure “GEAR” shows “5”.
-For shift schedule, refer to AT-299, "
Vehicle Speed When Performing and Releasing Complete
Lock-up".
-If “TESTING” does not appear on CONSULT-II for a long time, select “SELF-DIAG RESULTS”. In
case a 1st trip DTC other than P0744 is shown, refer to applicable “TROUBLE DIAGNOSIS FOR
DTC”.
3. Make sure that “OK” is displayed. (If “NG” is displayed, refer to “DIAGNOSTIC PROCEDURE”.)
Refer to AT-114, "
Diagnosis Procedure".
Item name Condition Display value (Approx.)
TCC SOLENOIDWhen performing slip lock-up 0.2 - 0.4 A
When performing lock-up 0.4 - 0.6 A
BCIA0031E