2006 INFINITI QX56 lock

AT-48
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
44-3Part 2
AT- 5 8
❏ AT-191, "Vehicle Cannot Be Started From D1"
❏ AT-194, "A/T Does Not Shift: D1 → D2"
❏ AT-196, "A/T Does Not Shift: D2 → D3"
❏ AT-198, "A/T Does Not Shift: D3 → D4"
Part 3
AT- 5 9
❏ AT-209, "A/T Does Not Shift: 5th gear → 4th gear"
❏ AT-212, "A/T Does Not Shift: 4th gear → 3rd gear"
❏ AT-213, "A/T Does Not Shift: 3rd gear → 2nd gear"
❏ AT-215, "A/T Does Not Shift: 2nd gear → 1st gear"
❏ AT-218, "Vehicle Does Not Decelerate By Engine Brake"
❏ Perform self-diagnostics Enter checks for detected items. AT- 8 6
❏ AT- 9 6 , "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-100, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-104, "DTC P0700 TCM"
❏ AT-105, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-109, "DTC P0717 TURBINE REVOLUTION SENSOR"
❏ AT- 111 , "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT- 11 6 , "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT- 11 8 , "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-120, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-122, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-124, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-127, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-132, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-134, "DTC P1730 A/T INTERLOCK"
❏ AT-137, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-139, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-141, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-143, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-145, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-147, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-149, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-153, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-155, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-157, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-159, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-161, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-163, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-165, "DTC P1846 ATF PRESSURE SWITCH 6"
5 ❏
Inspect each system for items found to be NG in the self-diagnostics and repair or replace the malfunction
parts.
6 ❏ Perform all road tests and enter the checks again for the required items. AT- 5 4
7❏
For any remaining NG items, perform the “diagnostics procedure ” and repair or replace the malfunction parts.
See the chart for diagnostics by symptoms. (This chart also contains other symptoms and inspection proce-
dures.) AT- 6 1
8
❏ Erase the results of the self-diagnostics from the TCM. AT- 3 9

AT-58
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
6. CHECK LOCK-UP
When releasing accelerator pedal from D5, check lock-up from D5 to L/U.

Refer to AT- 6 0 , "Vehicle Speed When Shifting Gears" .
With CONSULT-II
Select “TCC SOLENOID 0.00A ” with the “MAIN SIGNAL ” mode for A/T.
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 2ECS00CEI
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.

AT-60
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
Vehicle Speed When Shifting GearsECS00CEK
NORMAL MODE

At half throttle, the accelerator opening is 4/8 of the full opening.
TOW MODE

At half throttle, the accelerator opening is 4/8 of the full opening.
Vehicle Speed When Performing and Releasing Complete Lock-up ECS00CEL

At closed throttle, the accelerator opening is less than 1/8 condition.

At half throttle, the accelerator opening is 4/8 of the full opening.
Vehicle Speed When Performing and Releasing Slip Lock-upECS00CEM

At closed throttle, the accelerator opening is less than 1/8 condition.
Final
gear
ratio
Throttle position Vehicle speed km/h (MPH)
D
1 → D2D2 → D3D3 → D4D4 → D5D5 → D4D4 → D3D3 → D2D2 → D1
2.937 Full 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)
3.357 Full 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) 117 - 127
(73 - 79) 95 - 105
(59 - 65) 59 - 69
(37 - 43) 38 - 46
(24 - 29) 11 - 1 5
(7 - 10)
Final
gear
ratio Throttle position Vehicle speed km/h (MPH)
D
1 → D2D2 → D3D3 → D4D4 → D5D5 → D4D4 → D3D3 → D2D2 → D1
2.937 Full 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 50 - 54
(31 - 34) 81 - 89
(50 - 55) 113 - 123
(70 - 76) 135 - 145
(84 - 90) 109 - 119
(68 - 74) 68 - 78
(42 - 48) 44 - 52
(27 - 32) 11 - 1 5
(7 - 10)
3.357 Full 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 43 - 47
(27 - 29) 72 - 80
(45 - 50) 98 - 108
(61 - 67) 117 - 127
(73 - 79) 95 - 105
(59 - 65) 59 - 69
(37 - 43) 37 - 45
(23 - 28) 11 - 1 5
(7 - 10)
Final
gear ratio Throttle position Vehicle speed km/h (MPH)
Lock-up “ON ” Lock-up “OFF ”
2.937 Closed throttle
74 - 82 (46 - 51) 71 - 79 (45 - 49)
Half throttle 188 - 196 (117 - 122) 136 - 144 (85 - 90)
3.357 Closed throttle
65 - 73 (41 - 46) 62 - 70 (39 - 44)
Half throttle 168 - 176 (105 - 110) 118 - 126 (74 - 79)
Final
gear
ratioThrottle position Gear position
Vehicle speed km/h (MPH)
Slip lock-up “ON ” Slip lock-up “OFF ”
2.937 Closed throttle 4th
52 - 60 (33 - 38) 49 - 57 (31 - 36)
5th 52 - 60 (33 - 38) 49 - 57 (31 - 36)
3.357 Closed throttle 4th
46 - 54 (29 - 34) 43 - 51 (27 - 32)
5th 46 - 54 (29 - 34) 43 - 51 (27 - 32)

TROUBLE DIAGNOSISAT-63
DE
F
G H
I
J
K L
M A
B
AT
Revision: November 2009 2006 QX56
7
Shift
Shock Shock is too large for
upshift when acceler-
ator pedal is released.
ON vehicle1. Accelerator pedal position sensor
AT-124
2. Control cable adjustmentAT-227
3. Engine speed signal AT- 11 6
4. CAN communication line AT- 9 6
5. Turbine revolution sensorAT-109
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 111,
AT-132
7. Fluid level and state AT- 5 1
8. Control valve with TCMAT-230
OFF vehicle9. Front brake (brake band)
AT-25010. Input clutchAT-286
11. High and low reverse clutchAT-296
12. Direct clutchAT-298
8Shock is too large for
lock-up. ON vehicle1. Accelerator pedal position sensor
AT-124
2. Control cable adjustmentAT-227
3. Engine speed signal AT- 11 6
4. CAN communication line AT- 9 6
5. Turbine revolution sensorAT-109
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 111,
AT-132
7. Torque converter clutch solenoid valve AT- 11 8
8. Fluid level and state AT- 5 1
9. Control valve with TCMAT-230
OFF vehicle 10. Torque converter AT-264
9Shock is too large
during engine brake. ON vehicle
1. Accelerator pedal position sensor
AT-124
2. Control cable adjustmentAT-227
3. CAN communication line AT- 9 6
4. Fluid level and stateAT- 5 1
5. Control valve with TCMAT-230
OFF vehicle6. Front brake (brake band)
AT-2507. Input clutchAT-286
8. High and low reverse clutchAT-296
9. Direct clutchAT-298
No. ItemsSymptom Condition Diagnostic ItemReference
page

AT-68
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
22
Slips/Will
Not
Engage When
“D ” position,
remains in 5th gear. ON vehicle1. Fluid level and state
AT- 5 1
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 111,
AT- 1 3 2

3. ATF pressure switch 1 and front brake solenoid valve AT- 1 5 9
,
AT- 1 4 3
4. Line pressure test AT- 5 2
5. CAN communication lineAT- 9 6
6. Control valve with TCMAT- 2 3 0
OFF vehicle7. Front brake (brake band)
AT- 2 6 48. Input clutchAT- 2 8 6
9. Gear systemAT- 2 5 0
10. High and low reverse clutchAT- 2 9 6
23Vehicle cannot be
started from D
1 .
Refer to AT-191, "
Vehi-
cle Cannot Be Started
From D1" . ON vehicle
1. Fluid level and state
AT- 5 1
2. Accelerator pedal position sensorAT- 1 2 4
3. Line pressure test AT- 5 2
4. CAN communication lineAT- 9 6
5. Control valve with TCMAT- 2 3 0
OFF vehicle6. Torque converter
AT- 2 6 4
7. Oil pump assemblyAT- 2 8 2
8. 3rd one-way clutchAT- 2 8 4
9. 1st one-way clutchAT- 2 9 1
10. Gear systemAT- 2 5 0
11. Reverse brakeAT- 2 6 4
12. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
AT- 1 7
, AT- 1 8 .) AT- 2 6 4
13. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to
AT- 1 7
, AT- 1 8
.) AT- 2 6 4
24Does not lock-up.
Refer to
AT-203, "A/T
Does Not Perform
Lock-up" . ON vehicle1. Fluid level and state
AT- 5 1
2. Line pressure testAT- 5 2
3. Engine speed signalAT- 11 6
4. Turbine revolution sensorAT- 1 0 9
5. Torque converter clutch solenoid valve AT- 11 8
6. CAN communication line AT- 9 6
7. Control valve with TCMAT- 2 3 0
OFF vehicle8. Torque converter
AT- 2 6 49. Oil pump assemblyAT- 2 8 2
No. ItemsSymptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSISAT-69
DE
F
G H
I
J
K L
M A
B
AT
Revision: November 2009 2006 QX5625
Slips/Will
Not
engage Does not hold lock-up
condition.
Refer to
AT-205, "A/T
Does Not Hold Lock-
up Condition" . ON vehicle 1. Fluid level and state
AT- 5 1
2. Line pressure testAT- 5 2
3. Engine speed signalAT- 11 6
4. Turbine revolution sensorAT-109
5. Torque converter clutch solenoid valve AT- 11 8
6. CAN communication line AT- 9 6
7. Control valve with TCMAT-230
OFF vehicle8. Torque converter
AT-2649. Oil pump assemblyAT-282
26Lock-up is not
released.
Refer to
AT-207,
"Lock-up Is Not
Released" . ON vehicle1. Fluid level and state
AT- 5 1
2. Line pressure testAT- 5 2
3. Engine speed signalAT- 11 6
4. Turbine revolution sensorAT-109
5. Torque converter clutch solenoid valve AT- 11 8
6. CAN communication line AT- 9 6
7. Control valve with TCMAT-230
OFF vehicle8. Torque converter
AT-2649. Oil pump assemblyAT-282
27No shock at all or the
clutch slips when
vehicle changes
speed D
1 →
D2 . ON vehicle
1. Fluid level and state
AT- 5 1
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 111,
AT-132
3. ATF pressure switch 5 and direct clutch solenoid valve AT-163,
AT-147
4. CAN communication line AT- 9 6
5. Line pressure testAT- 5 2
6. Control valve with TCMAT-230
OFF vehicle7. Torque converter
AT-264
8. Oil pump assemblyAT-282
9. 3rd one-way clutchAT-284
10. Gear systemAT-250
11. Direct clutchAT-298
12. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 7
, AT- 1 8
.) AT-264
No. Items
Symptom Condition Diagnostic ItemReference
page

AT-76
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
41
Slips/Will
Not
Engage While accelerating in
5th, engine races or
slippage occurs.
ON vehicle
1. Fluid level and state
AT- 5 1
2. Line pressure testAT- 5 2
3. Accelerator pedal position sensorAT- 1 2 4
4. CAN communication line AT- 9 6
5. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 9,
AT- 1 4 3
6. Control valve with TCM AT- 2 3 0
OFF vehicle7. Torque converter
AT- 2 6 4
8. Oil pump assemblyAT- 2 8 2
9. Front brake (brake band)AT- 2 6 4
10. Input clutchAT- 2 8 6
11. Gear systemAT- 2 5 0
12. High and low reverse clutchAT- 2 9 6
42Slips at lock-up. ON vehicle1. Fluid level and state
AT- 5 1
2. Line pressure testAT- 5 2
3. Engine speed signalAT- 11 6
4. Turbine revolution sensorAT- 1 0 9
5. Torque converter clutch solenoid valve AT- 11 8
6. CAN communication line AT- 9 6
7. Control valve with TCMAT- 2 3 0
OFF vehicle8. Torque converter
AT- 2 6 49. Oil pump assemblyAT- 2 8 2
43No creep at all.
Refer to
AT-186, "
Vehi-
cle Does Not Creep
Backward In “R” Posi-
tion" , AT-189, "Ve h i-
cle Does Not Creep
Forward In “D” Posi-
tion"
ON vehicle 1. Fluid level and state
AT- 5 1
2. Line pressure testAT- 5 2
3. Accelerator pedal position sensorAT- 1 2 4
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 6 3,
AT- 1 4 7
5. PNP switch AT- 1 0 5
6. CAN communication line AT- 9 6
7. Control cable adjustmentAT- 2 2 7
8. Control valve with TCMAT- 2 3 0
OFF vehicle9. Torque converter
AT- 2 6 4
10. Oil pump assemblyAT- 2 8 2
11. 1st one-way clutchAT- 2 9 1
12. Gear systemAT- 2 5 0
13. Reverse brakeAT- 2 6 4
14. Direct clutchAT- 2 9 8
15. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
AT- 1 7
, AT- 1 8 .) AT- 2 6 4
16. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to
AT- 1 7
, AT- 1 8
.) AT- 2 6 4
No. Items
Symptom Condition Diagnostic ItemReference
page

AT-78
TROUBLE DIAGNOSIS
Revision: November 20092006 QX56
48
Others Shift point is low in “
D”
position. ON vehicle1. Vehicle speed sensor A/T and vehicle speed sensor MTR
AT- 111
,
AT- 1 3 2
2. Accelerator pedal position sensor AT- 1 2 4
3. CAN communication line AT- 9 6
4. Control valve with TCMAT- 2 3 0
49Judder occurs during
lock-up. ON vehicle1. Fluid level and state
AT- 5 1
2. Engine speed signalAT- 11 6
3. Turbine revolution sensorAT- 1 0 9
4. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 111,
AT- 1 3 2
5. Accelerator pedal position sensor AT- 1 2 4
6. CAN communication line AT- 9 6
7. Torque converter clutch solenoid valveAT- 11 8
8. Control valve with TCMAT- 2 3 0
OFF vehicle 9. Torque converter AT- 2 6 4
50Strange noise in “
R”
position. ON vehicle
1. Fluid level and state
AT- 5 1
2. Engine speed signalAT- 11 6
3. CAN communication line AT- 9 6
4. Control valve with TCMAT- 2 3 0
OFF vehicle5. Torque converter
AT- 2 6 4
6. Oil pump assemblyAT- 2 8 2
7. Gear systemAT- 2 5 0
8. High and low reverse clutchAT- 2 9 6
9. Reverse brakeAT- 2 6 4
51Strange noise in “
N”
position. ON vehicle
1. Fluid level and state
AT- 5 1
2. Engine speed signalAT- 11 6
3. CAN communication line AT- 9 6
4. Control valve with TCMAT- 2 3 0
OFF vehicle5. Torque converter
AT- 2 6 46. Oil pump assemblyAT- 2 8 2
7. Gear systemAT- 2 5 0
52Strange noise in “
D”
position. ON vehicle
1. Fluid level and state
AT- 5 1
2. Engine speed signalAT- 11 6
3. CAN communication line AT- 9 6
4. Control valve with TCMAT- 2 3 0
OFF vehicle5. Torque converter
AT- 2 6 4
6. Oil pump assemblyAT- 2 8 2
7. Gear systemAT- 2 5 0
8. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 7
, AT- 1 8
.) AT- 2 6 4
No. Items
Symptom Condition Diagnostic ItemReference
page