2004 INFINITI QX56 lock

TROUBLE DIAGNOSIS
AT-49
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Revision: August 20072004 QX56
44-3Part 2
AT- 6 5
❏ AT-203, "Vehicle Cannot Be Started From D1"
❏ AT-206, "A/T Does Not Shift: D1 → D2"
❏ AT-208, "A/T Does Not Shift: D2 → D3"
❏ AT-210, "A/T Does Not Shift: D3 → D4"
Part 3
AT- 6 6
❏ AT-221, "A/T Does Not Shift: 5th gear → 4th gear"
❏ AT-224, "A/T Does Not Shift: 4th gear → 3rd gear"
❏ AT-225, "A/T Does Not Shift: 3rd gear → 2nd gear"
❏ AT-227, "A/T Does Not Shift: 2nd gear → 1st gear"
❏ AT-230, "Vehicle Does Not Decelerate By Engine Brake"
❏ Perform self-diagnostics Enter checks for detected items. AT- 9 3
❏ AT-103, "DTC U1000 CAN COMMUNICATION LINE"
❏ AT-105, "DTC P0615 START SIGNAL CIRCUIT"
❏ AT-108, "DTC P0700 TCM"
❏ AT-109, "DTC P0705 PARK/NEUTRAL POSITION SWITCH"
❏ AT-112, "DTC P0720 VEHICLE SPEED SENSOR A/T (REVOLUTION SENSOR)"
❏ AT-115, "DTC P0725 ENGINE SPEED SIGNAL"
❏ AT-118, "DTC P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE"
❏ AT-121, "DTC P0744 A/T TCC S/V FUNCTION (LOCK-UP)"
❏ AT-124, "DTC P0745 LINE PRESSURE SOLENOID VALVE"
❏ AT-127, "DTC P1702 TRANSMISSION CONTROL MODULE (RAM)"
❏ AT-128, "DTC P1703 TRANSMISSION CONTROL MODULE (ROM)"
❏ AT-129, "DTC P1705 THROTTLE POSITION SENSOR"
❏ AT-131, "DTC P1710 A/T FLUID TEMPERATURE SENSOR CIRCUIT"
❏ AT-134, "DTC P1716 TURBINE REVOLUTION SENSOR"
❏ AT-136, "DTC P1721 VEHICLE SPEED SENSOR MTR"
❏ AT-139, "DTC P1730 A/T INTERLOCK"
❏ AT-142, "DTC P1731 A/T 1ST ENGINE BRAKING"
❏ AT-145, "DTC P1752 INPUT CLUTCH SOLENOID VALVE"
❏ AT-148, "DTC P1754 INPUT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-151, "DTC P1757 FRONT BRAKE SOLENOID VALVE"
❏ AT-154, "DTC P1759 FRONT BRAKE SOLENOID VALVE FUNCTION"
❏ AT-157, "DTC P1762 DIRECT CLUTCH SOLENOID VALVE"
❏ AT-160, "DTC P1764 DIRECT CLUTCH SOLENOID VALVE FUNCTION"
❏ AT-163, "DTC P1767 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE"
❏ AT-166, "DTC P1769 HIGH AND LOW REVERSE CLUTCH SOLENOID VALVE
FUNCTION"
❏ AT-169, "DTC P1772 LOW COAST BRAKE SOLENOID VALVE"
❏ AT-172, "DTC P1774 LOW COAST BRAKE SOLENOID VALVE FUNCTION"
❏ AT-175, "DTC P1841 ATF PRESSURE SWITCH 1"
❏ AT-178, "DTC P1843 ATF PRESSURE SWITCH 3"
❏ AT-181, "DTC P1845 ATF PRESSURE SWITCH 5"
❏ AT-184, "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- 6 1
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 8
8❏ Erase the results of the self-diagnostics from the TCM.AT- 4 0

TROUBLE DIAGNOSIS
AT-65
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Revision: August 20072004 QX56
6. CHECK LOCK-UP
When releasing accelerator pedal from D5, check lock-up from D5 to L/U.

Refer to AT- 6 7 , "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 continue
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 hold does not 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- 6 5
).
NO >> Enter a check mark at “A/T does not shift-down” on the diagnostics worksheet, then continue the
road test. Go to Cruise test - Part 2 (Refer to AT- 6 5
).
Cruise Test - Part 2UCS002D1
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.

TROUBLE DIAGNOSIS
AT-67
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Revision: August 20072004 QX56
Vehicle Speed When Shifting GearsUCS002D3
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 UCS002D4

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-upUCS002D5

At closed throttle, the accelerator opening is less than 1/8 condition. 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)117 - 127
(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
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 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)
3.357Full 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 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
ratioThrottle positionVehicle speed km/h (MPH)
Lock-up “ON” Lock-up “OFF”
2.937Closed throttle 74 - 82 (46 - 51) 71 - 79 (45 - 49)
Half throttle 188 - 196 (117 - 122) 136 - 144 (85 - 90)
3.357Closed throttle 65 - 73 (41 - 46) 62 - 70 (39 - 44)
Half throttle 168 - 176 (105 - 110) 118 - 126 (74 - 79)
Final
gear
ratioThrottle position Gear positionVehicle speed km/h (MPH)
Slip lock-up “ON” Slip lock-up “OFF”
2.937 Closed throttle4th 52 - 60 (33 - 38) 49 - 57 (31 - 36)
5th 52 - 60 (33 - 38) 49 - 57 (31 - 36)
3.357 Closed throttle4th 46 - 54 (29 - 34) 43 - 51 (27 - 32)
5th 46 - 54 (29 - 34) 43 - 51 (27 - 32)

AT-70
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
7
Shift
ShockShock is too large for
upshift when acceler-
ator pedal is released.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. Engine speed signalAT - 11 5
4. CAN communication lineAT- 1 0 3
5. Turbine revolution sensorAT- 1 3 4
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
7. Fluid level and stateAT-5 8
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Front brake (brake band)AT- 2 6 110. Input clutchAT- 2 9 5
11. High and low reverse clutchAT- 3 0 5
12. Direct clutchAT- 3 0 7
8Shock is too large for
lock-up.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. Engine speed signalAT - 11 5
4. CAN communication lineAT- 1 0 3
5. Turbine revolution sensorAT- 1 3 4
6. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
7. Torque converter clutch solenoid valveAT - 11 8
8. Fluid level and stateAT-5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. Torque converterAT- 2 7 3
9Shock is too large
during engine brake.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. CAN communication lineAT- 1 0 3
4. Fluid level and stateAT-5 8
5. Control valve with TCMAT- 2 4 1
OFF vehicle6. Front brake (brake band)AT- 2 6 17. Input clutchAT- 2 9 5
8. High and low reverse clutchAT- 3 0 5
9. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
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TROUBLE DIAGNOSIS
AT-75
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Revision: August 20072004 QX56
22
Slips/Will
Not
EngageWhen “D” position,
remains in 5th gear.ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6

3. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5
,
AT- 1 5 1
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. Front brake (brake band)AT- 2 7 38. Input clutchAT- 2 9 5
9. Gear systemAT- 2 6 1
10. High and low reverse clutchAT- 3 0 5
23Vehicle cannot be
started from D
1 .
Refer toAT- 2 0 3 , "
Vehi-
cle Cannot Be Started
From D1" .ON vehicle1. Fluid level and stateAT- 5 8
2. Accelerator pedal position sensorAT- 1 2 9
3. Line pressure testAT- 5 9
4. CAN communication lineAT- 1 0 3
5. Control valve with TCMAT- 2 4 1
OFF vehicle6. Torque converterAT- 2 7 3
7. Oil pump assemblyAT- 2 9 0
8. 3rd one-way clutchAT- 2 9 2
9. 1st one-way clutchAT- 3 0 0
10. Gear systemAT- 2 6 1
11. Reverse brakeAT- 2 7 3
12. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
AT- 1 8
, AT-1 9 .)AT- 2 7 3
13. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT-1 8
, AT - 1 9
.)AT- 2 7 3
24Does not lock-up.
Refer to AT- 2 1 5 , "A/T
Does Not Perform
Lock-up" .ON vehicle1. Fluid level and stateAT- 5 8
2. Line pressure testAT- 5 9
3. Engine speed signalAT- 11 5
4. Turbine revolution sensorAT- 1 3 4
5. Torque converter clutch solenoid valveAT- 11 8
6. CAN communication lineAT- 1 0 3
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 39. Oil pump assemblyAT- 2 9 0
No. Items Symptom Condition Diagnostic ItemReference
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AT-76
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
25
Slips/Will
Not
engageDoes not hold lock-up
condition.
Refer toAT- 2 1 7 , "A/T
Does Not Hold Lock-
up Condition" .ON vehicle1. Fluid level and stateAT-5 8
2. Line pressure testAT-5 9
3. Engine speed signalAT - 11 5
4. Turbine revolution sensorAT- 1 3 4
5. Torque converter clutch solenoid valveAT - 11 8
6. CAN communication lineAT- 1 0 3
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 39. Oil pump assemblyAT- 2 9 0
26Lock-up is not
released.
Refer toAT- 2 1 9 ,
"Lock-up Is Not
Released" .ON vehicle1. Fluid level and stateAT-5 8
2. Line pressure testAT-5 9
3. Engine speed signalAT - 11 5
4. Turbine revolution sensorAT- 1 3 4
5. Torque converter clutch solenoid valveAT - 11 8
6. CAN communication lineAT- 1 0 3
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 39. Oil pump assemblyAT- 2 9 0
27No shock at all or the
clutch slips when
vehicle changes
speed D
1 → D2 . ON vehicle1. Fluid level and stateAT-5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
4. CAN communication lineAT- 1 0 3
5. Line pressure testAT-5 9
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. Torque converterAT- 2 7 3
8. Oil pump assemblyAT- 2 9 0
9. 3rd one-way clutchAT- 2 9 2
10. Gear systemAT- 2 6 1
11. Direct clutchAT- 3 0 7
12. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 8
, AT- 1 9
.)AT- 2 7 3
No. Items Symptom Condition Diagnostic ItemReference
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TROUBLE DIAGNOSIS
AT-83
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Revision: August 20072004 QX56
41
Slips/Will
Not
Engage While accelerating in
5th, engine races or
slippage occurs.ON vehicle1. Fluid level and stateAT- 5 8
2. Line pressure testAT- 5 9
3. Accelerator pedal position sensorAT- 1 2 9
4. CAN communication lineAT- 1 0 3
5. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. Torque converterAT- 2 7 3
8. Oil pump assemblyAT- 2 9 0
9. Front brake (brake band)AT- 2 7 3
10. Input clutchAT- 2 9 5
11. Gear systemAT- 2 6 1
12. High and low reverse clutchAT- 3 0 5
42 Slips at lock-up.ON vehicle1. Fluid level and stateAT- 5 8
2. Line pressure testAT- 5 9
3. Engine speed signalAT- 11 5
4. Turbine revolution sensorAT- 1 3 4
5. Torque converter clutch solenoid valveAT- 11 8
6. CAN communication lineAT- 1 0 3
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 39. Oil pump assemblyAT- 2 9 0
43No creep at all.
Refer toAT- 1 9 8 , "
Vehi-
cle Does Not Creep
Backward In “R” Posi-
tion" , AT-201, "Ve hi-
cle Does Not Creep
Forward In “D” Posi-
tion"
ON vehicle1. Fluid level and stateAT- 5 8
2. Line pressure testAT- 5 9
3. Accelerator pedal position sensorAT- 1 2 9
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
5. PNP switchAT- 1 0 9
6. CAN communication lineAT- 1 0 3
7. Control cable adjustmentAT- 2 3 4
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Torque converterAT- 2 7 3
10. Oil pump assemblyAT- 2 9 0
11. 1st one-way clutchAT- 3 0 0
12. Gear systemAT- 2 6 1
13. Reverse brakeAT- 2 7 3
14. Direct clutchAT- 3 0 7
15. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to
AT- 1 8
, AT-1 9 .)AT- 2 7 3
16. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT-1 8
, AT - 1 9
.)AT- 2 7 3
No. Items Symptom Condition Diagnostic ItemReference
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TROUBLE DIAGNOSIS
AT-85
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Revision: August 20072004 QX56
48
OthersShift point is low in “D”
position.ON vehicle1. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2
,
AT- 1 3 6
2. Accelerator pedal position sensorAT- 1 2 9
3. CAN communication lineAT- 1 0 3
4. Control valve with TCMAT- 2 4 1
49Judder occurs during
lock-up.ON vehicle1. Fluid level and stateAT- 5 8
2. Engine speed signalAT- 11 5
3. Turbine revolution sensorAT- 1 3 4
4. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
5. Accelerator pedal position sensorAT- 1 2 9
6. CAN communication lineAT- 1 0 3
7. Torque converter clutch solenoid valveAT- 11 8
8. Control valve with TCMAT- 2 4 1
OFF vehicle 9. Torque converterAT- 2 7 3
50Strange noise in “R”
position.ON vehicle1. Fluid level and stateAT- 5 8
2. Engine speed signalAT- 11 5
3. CAN communication lineAT- 1 0 3
4. Control valve with TCMAT- 2 4 1
OFF vehicle5. Torque converterAT- 2 7 3
6. Oil pump assemblyAT- 2 9 0
7. Gear systemAT- 2 6 1
8. High and low reverse clutchAT- 3 0 5
9. Reverse brakeAT- 2 7 3
51Strange noise in “N”
position.ON vehicle1. Fluid level and stateAT- 5 8
2. Engine speed signalAT- 11 5
3. CAN communication lineAT- 1 0 3
4. Control valve with TCMAT- 2 4 1
OFF vehicle5. Torque converterAT- 2 7 36. Oil pump assemblyAT- 2 9 0
7. Gear systemAT- 2 6 1
52Strange noise in “D”
position.ON vehicle1. Fluid level and stateAT- 5 8
2. Engine speed signalAT- 11 5
3. CAN communication lineAT- 1 0 3
4. Control valve with TCMAT- 2 4 1
OFF vehicle5. Torque converterAT- 2 7 3
6. Oil pump assemblyAT- 2 9 0
7. Gear systemAT- 2 6 1
8. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT-1 8
, AT - 1 9
.)AT- 2 7 3
No. Items Symptom Condition Diagnostic ItemReference
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