2007 INFINITI QX56 engine

AT-56
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
3. Turn ignition switch to “START” position.
Does the engine start in either position?
YES >> Stop the road test and go to AT-168, "Engine Cannot Be Started in "P" or "N" Position".
NO >> GO TO 3.
3.CHECK “P” POSITION FUNCTIONS
1. Move selector lever to “P” position.
2. Turn ignition switch to “OFF” position.
3. Release the parking brake.
4. Push the vehicle forward or backward.
5. Engage the parking brake.
When you push the vehicle with disengaging the parking brake, does it move?
YES >> Enter a check mark at “In “P” Position Vehicle Moves When Pushed” on the diagnostics work-
sheet, then continue the road test.
NO >> GO TO 4.
4.CHECK “N” POSITION FUNCTIONS
1. Start the engine.
2. Move selector lever to “N” position.
3. Release the parking brake.
Does vehicle move forward or backward?
YES >> Enter a check mark at “In “N” Position Vehicle Moves” on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 5.
5.CHECK SHIFT SHOCK
1. Engage the brake.
2. Move selector lever to “D” position.
When the transmission is shifted from
“N” to “D”, is there an excessive shock?
YES >> Enter a check mark at “Large Shock ("N" to "D" Position) on the diagnostics worksheet, then con-
tinue the road test.
NO >> GO TO 6.
6.CHECK “R” POSITION FUNCTIONS
1. Engage the brake.
2. Move selector lever to “R” position.
3. Release the brake for 4 to 5 seconds.
Does the vehicle creep backward?
YES >> GO TO 7.
NO >> Enter a check mark at “Vehicle Does Not Creep Backward In "R" Position” on the diagnostics
worksheet, then continue the road test.
7.CHECK “D” POSITION FUNCTIONS
Inspect whether the vehicle creeps forward when the transmission is put into the “D” position.
Does the vehicle creep forward in the
“D” positions?
YES >> Go to AT-56, "Cruise Test - Part 1", AT-58, "Cruise Test - Part 2", and AT-59, "Cruise Test - Part 3".
NO >> Enter a check mark at “Vehicle Does Not Creep Forward in "D" Position” on the diagnostics work-
sheet, then continue the road test.
Cruise Test - Part 1INFOID:0000000003532251
1.CHECK STARTING OUT FROM D1
1. Drive the vehicle for about 10 minutes to warm up the engine oil and ATF.
Appropriate temperature for the ATF: 50 - 80°C (122 - 176°F)
2. Park the vehicle on a level surface.
3. Move selector lever to “P” position.
4. Start the engine.
5. Move selector lever to “D” position.

AT-58
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
Does it lock-up?
YES >> GO TO 7.
NO >> Enter a check mark at “A/T Does Not Perform Lock-up” on the diagnostics worksheet, then con-
tinue the road test.
7.CHECK LOCK-UP HOLD
Does it maintain lock-up status?
YES >> GO TO 8.
NO >> Enter a check mark at “A/T Does Not Hold Lock-up Condition” on the diagnostics worksheet, then
continue the road test.
8.CHECK LOCK-UP RELEASE
Check lock-up cancellation by depressing brake pedal lightly to decelerate.
With CONSULT-II
Select “TCC SOLENOID 0.00A” with the “MAIN SIGNAL” mode for A/T.
Does lock-up cancel?
YES >> GO TO 9.
NO >> Enter a check mark at “Lock-up Is Not Released” on the diagnostics worksheet, then continue the
road test.
9.CHECK SHIFT-DOWN D5 → D4
Decelerate by pressing lightly on the brake pedal.
With CONSULT-II
Read the gear position and engine speed.
When the A/T shift-down D5
→ D4, does the engine speed drop smoothly back to idle?
YES >> 1. Stop the vehicle.
2. Go to Cruise test - Part 2 (Refer to AT- 5 8
).
NO >> Enter a check mark at “Engine Speed Does Not Return to Idle” on the diagnostics worksheet, then
continue the road test. Go to Cruise test - Part 2 (Refer to AT- 5 8
).
Cruise Test - Part 2INFOID:0000000003532252
1.CHECK STARTING FROM D1
1. Move selector lever the “D” position.
2. Accelerate at half throttle.
With CONSULT-II
Read the gear position.
Does it start from D1?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle Cannot Be Started From D1” on the diagnostics worksheet, then
continue the road test.
2.CHECK SHIFT-UP D1 → D2
Press the accelerator pedal down all the way and inspect whether or not the transmission shifts up (D1 → D2)
at the correct speed.
• Refer to AT-59, "
Vehicle Speed When Shifting Gears".
With CONSULT-II
Read the gear position, throttle position and vehicle speed.
Does the A/T shift-up D1
→ D2 at the correct speed?
YES >> GO TO 3.
NO >> Enter a check mark at “Vehicle Does Not Shift: D1 → D2” on the diagnostics worksheet, then con-
tinue the road test.
3.CHECK SHIFT-UP D2 → D3
Press the accelerator pedal down all the way and inspect whether or not the transmission shifts up (D2 → D3)
at the correct speed.

TROUBLE DIAGNOSIS
AT-59
< SERVICE INFORMATION >
D
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AT
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• Refer to AT-59, "Vehicle Speed When Shifting Gears".
With CONSULT-II
Read the gear position, throttle position and vehicle speed.
Does the A/T shift-up D2
→ D3 at the correct speed?
YES >> GO TO 4.
NO >> Enter a check mark at “Vehicle Does Not Shift: D2 → D3” on the diagnostics worksheet, then con-
tinue the road test.
4.CHECK SHIFT-UP D3 → D4 AND ENGINE BRAKE
When the transmission changes speed D3 → D4, return the accelerator pedal.
Does the A/T shift-up D3
→ D4 and apply the engine brake?
YES >> 1. Stop the vehicle.
2. See AT-59, "
Cruise Test - Part 3".
NO >> Enter a check mark at “Vehicle Does Not Shift: D3 → D4” on the diagnostics worksheet, then con-
tinue the road test.
Cruise Test - Part 3INFOID:0000000003532253
1.CHECK SHIFT-DOWN
During D
5 driving, move gear selector from D → 4 → 3 → 2 → 1.
With CONSULT-II
Read the gear position.
Is downshifting correctly performed?
YES >> GO TO 2.
NO >> Enter a check mark at “Vehicle does not shift” at the corresponding position (5th → 4th, 4th → 3rd,
3rd → 2nd, 2nd → 1st) on the diagnostics worksheet, then continue the road test.
2.CHECK ENGINE BRAKE
Does engine braking effectively reduce speed in 1
1 position?
YES >> 1. Stop the vehicle.
2. Carry out the self-diagnostics. Refer to AT-83, "
CONSULT-II Function (A/T)".
NO >> Enter a check mark at “Vehicle Does Not Decelerate By Engine Brake” on the diagnostics work-
sheet, then continue trouble diagnosis.
Vehicle Speed When Shifting GearsINFOID:0000000003532254
NORMAL MODE
• At half throttle, the accelerator opening is 4/8 of the full opening.
TOW MODE
Final
gear
ratioThrottle positionVehicle speed km/h (MPH)
D
1 →D2D2 →D3D3 →D4D4 →D5D5 →D4D4 →D3D3 →D2D2 →D1
2.937Full throttle 70 - 74
(44 - 46)112 - 120
(70 - 75)176 - 186
(110 - 116)249 - 259
(155 - 161)245 - 255
(152 - 159)166 - 176
(103 - 110)100 - 108
(62 - 67)43 - 47
(27 - 30)
Half throttle 46 - 50
(28 - 31)74 - 82
(46 - 51)103 - 113
(64 - 70)135 - 145
(84 - 90)109 - 119
(68 - 74)69 - 79
(43 - 49)44 - 52
(27 - 32)11 - 1 5
(7 - 10)
3.357Full throttle 61 - 65
(38 - 41)97 - 105
(61 - 66)153 - 163
(95 - 102)236 - 246
(147 - 153)232 - 242
(144 - 151)143 - 153
(89 - 95)87 - 95
(54 - 59)43 - 47
(27 - 29)
Half throttle 41 - 45
(26 - 28)66 - 74
(41 - 46)89 - 99
(56 - 62)11 7 - 1 2 7
(73 - 79)95 - 105
(59 - 65)59 - 69
(37 - 43)38 - 46
(24 - 29)11 - 1 5
(7 - 10)
Final
gear
ratioThrottle positionVehicle speed km/h (MPH)
D
1 →D2D2 →D3D3 →D4D4 →D5D5 →D4D4 →D3D3 →D2D2 →D1

TROUBLE DIAGNOSIS
AT-61
< SERVICE INFORMATION >
D
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F
G
H
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K
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MA
B
AT
N
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P
No. Items Symptom Condition Diagnostic ItemReference
page
1
Shift
ShockLarge shock. (“N” →“
D” position)
Refer to AT- 1 7 0 ,
"Large Shock ("N" to
"D" Position)".ON vehicle1. Engine idle speedEC-75
2. Engine speed signalAT-109
3. Accelerator pedal position sensorAT- 11 7
4. Control cable adjustmentAT-208
5. ATF temperature sensorAT- 11 9
6. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 0,
AT-134
7. CAN communication lineAT- 9 1
8. Fluid level and stateAT- 5 1
9. Line pressure testAT- 5 1
10. Control valve with TCMAT-210
OFF vehicle11. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 9, AT- 2 0.)AT-240
2Shock is too large
when changing D1 →
D
2.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT-208
3. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT-138
4. CAN communication lineAT- 9 1
5. Engine speed signalAT-109
6. Turbine revolution sensorAT-103
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT-124
8. Fluid level and stateAT- 5 1
9. Control valve with TCMAT-210
OFF vehicle 10. Direct clutchAT-274
3Shock is too large
when changing D2 →
D
3.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT-208
3. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 5 6,
AT-142
4. CAN communication lineAT- 9 1
5. Engine speed signalAT-109
6. Turbine revolution sensorAT-103
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT-124
8. Fluid level and stateAT- 5 1
9. Control valve with TCMAT-210
OFF vehicle 10. High and low reverse clutchAT-272

AT-62
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
4
Shift
ShockShock is too large
when changing D3 →
D
4.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT- 2 0 8
3. ATF pressure switch 3 and input clutch solenoid valveAT- 1 5 2,
AT- 1 3 0
4. CAN communication lineAT- 9 1
5. Engine speed signalAT- 1 0 9
6. Turbine revolution sensorAT- 1 0 3
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT- 1 2 4
8. Fluid level and stateAT- 5 1
9. Control valve with TCMAT- 2 1 0
OFF vehicle 10. Input clutchAT- 2 6 2
5Shock is too large
when changing D4 →
D
5.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT- 2 0 8
3. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 0,
AT- 1 3 4

4. CAN communication lineAT- 9 1
5. Engine speed signalAT- 1 0 9
6. Turbine revolution sensorAT- 1 0 3
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT- 1 2 4
8. Fluid level and stateAT- 5 1
9. Control valve with TCMAT- 2 1 0
OFF vehicle10. Front brake (brake band)AT- 2 2 811. Input clutchAT- 2 6 2
6Shock is too large for
downshift when accel-
erator pedal is
pressed.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT- 2 0 8
3. CAN communication lineAT- 9 1
4. Engine speed signalAT- 1 0 9
5. Turbine revolution sensorAT- 1 0 3
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT- 1 2 4
7. Fluid level and stateAT- 5 1
8. Control valve with TCMAT- 2 1 0
OFF vehicle9. Front brake (brake band)AT- 2 2 8
10. Input clutchAT- 2 6 2
11. High and low reverse clutchAT- 2 7 2AT-
272
12. Direct clutchAT- 2 7 4
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-63
< SERVICE INFORMATION >
D
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AT
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7
Shift
ShockShock is too large for
upshift when accelera-
tor pedal is released.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT-208
3. Engine speed signalAT-109
4. CAN communication lineAT- 9 1
5. Turbine revolution sensorAT-103
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT-124
7. Fluid level and stateAT- 5 1
8. Control valve with TCMAT-210
OFF vehicle9. Front brake (brake band)AT-22810. Input clutchAT-262
11. High and low reverse clutchAT-272
12. Direct clutchAT-274
8Shock is too large for
lock-up.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT-208
3. Engine speed signalAT-109
4. CAN communication lineAT- 9 1
5. Turbine revolution sensorAT-103
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT-124
7. Torque converter clutch solenoid valveAT- 111
8. Fluid level and stateAT- 5 1
9. Control valve with TCMAT-210
OFF vehicle 10. Torque converterAT-240
9Shock is too large dur-
ing engine brake.ON vehicle1. Accelerator pedal position sensorAT- 11 7
2. Control cable adjustmentAT-208
3. CAN communication lineAT- 9 1
4. Fluid level and stateAT- 5 1
5. Control valve with TCMAT-210
OFF vehicle6. Front brake (brake band)AT-2287. Input clutchAT-262
8. High and low reverse clutchAT-272
9. Direct clutchAT-274
No. Items Symptom Condition Diagnostic ItemReference
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AT-68
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
22
Slips/Will
Not En-
gageWhen “D” position, re-
mains in 5th gear.ON vehicle1. Fluid level and stateAT- 5 1
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT- 1 2 4

3. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 0
,
AT- 1 3 4
4. Line pressure testAT- 5 1
5. CAN communication lineAT- 9 1
6. Control valve with TCMAT- 2 1 0
OFF vehicle7. Front brake (brake band)AT- 2 4 08. Input clutchAT- 2 6 2
9. Gear systemAT- 2 2 8
10. High and low reverse clutchAT- 2 7 2
23Vehicle cannot be
started from D
1.
Refer to AT-177, "
Ve -
hicle Cannot Be Start-
ed from D1".ON vehicle1. Fluid level and stateAT- 5 1
2. Accelerator pedal position sensorAT- 11 7
3. Line pressure testAT- 5 1
4. CAN communication lineAT- 9 1
5. Control valve with TCMAT- 2 1 0
OFF vehicle6. Torque converterAT- 2 4 0
7. Oil pump assemblyAT- 2 5 8
8. 3rd one-way clutchAT- 2 6 0
9. 1st one-way clutchAT- 2 6 7
10. Gear systemAT- 2 2 8
11. Reverse brakeAT- 2 4 0
12. Forward one-way clutch (Parts behind drum support is im-
possible to perform inspection by disassembly. Refer to AT-
19, AT- 2 0.)AT- 2 4 0
13. 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
24Does not lock-up.
Refer to AT-187, "A/T
Does Not Perform
Lock-up".ON vehicle1. Fluid level and stateAT- 5 1
2. Line pressure testAT- 5 1
3. Engine speed signalAT- 1 0 9
4. Turbine revolution sensorAT- 1 0 3
5. Torque converter clutch solenoid valveAT- 111
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT- 2 1 0
OFF vehicle8. Torque converterAT- 2 4 09. Oil pump assemblyAT- 2 5 8
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-69
< SERVICE INFORMATION >
D
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Slips/Will
Not en-
gageDoes not hold lock-up
condition.
Refer to AT- 1 8 9 , "A/T
Does Not Hold Lock-
up Condition".ON vehicle1. Fluid level and stateAT- 5 1
2. Line pressure testAT- 5 1
3. Engine speed signalAT-109
4. Turbine revolution sensorAT-103
5. Torque converter clutch solenoid valveAT- 111
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT-210
OFF vehicle8. Torque converterAT-2409. Oil pump assemblyAT-258
26Lock-up is not re-
leased.
Refer to AT- 1 9 0 ,
"Lock-up Is Not Re-
leased".ON vehicle1. Fluid level and stateAT- 5 1
2. Line pressure testAT- 5 1
3. Engine speed signalAT-109
4. Turbine revolution sensorAT-103
5. Torque converter clutch solenoid valveAT- 111
6. CAN communication lineAT- 9 1
7. Control valve with TCMAT-210
OFF vehicle8. Torque converterAT-2409. Oil pump assemblyAT-258
27No shock at all or the
clutch slips when vehi-
cle changes speed D1
→ D
2. ON vehicle1. Fluid level and stateAT- 5 1
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT-124
3. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT-138
4. CAN communication lineAT- 9 1
5. Line pressure testAT- 5 1
6. Control valve with TCMAT-210
OFF vehicle7. Torque converterAT-240
8. Oil pump assemblyAT-258
9. 3rd one-way clutchAT-260
10. Gear systemAT-228
11. Direct clutchAT-274
12. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 9
, AT- 2 0.)AT-240
No. Items Symptom Condition Diagnostic ItemReference
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