2007 INFINITI QX56 engine

TROUBLE DIAGNOSIS
AT-71
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
30
Slips/Will
Not en-
gageNo shock at all or the
clutch slips when vehi-
cle changes speed D4
→ D
5.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 1 and front brake solenoid valveAT- 1 5 0,
AT-134
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT-138
5. CAN communication lineAT- 9 1
6. Line pressure testAT- 5 1
7. Control valve with TCMAT-210
OFF vehicle8. Torque converterAT-240
9. Oil pump assemblyAT-258
10. Front brake (brake band)AT-240
11. Input clutchAT-262
12. Gear systemAT-228
13. High and low reverse clutchAT-272
31When you press the
accelerator pedal and
shift speed D5 → D4
the engine idles or the
transmission slips.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 1 and front brake solenoid valveAT- 1 5 0,
AT-134
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT-138
5. CAN communication lineAT- 9 1
6. Line pressure testAT- 5 1
7. Control valve with TCMAT-210
OFF vehicle8. Torque converterAT-240
9. Oil pump assemblyAT-258
10. Input clutchAT-262
11. Gear systemAT-228
12. High and low reverse clutchAT-272
13. Direct clutchAT-274
No. Items Symptom Condition Diagnostic ItemReference
page

AT-72
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
32
Slips/Will
Not en-
gageWhen you press the
accelerator pedal and
shift speed D4 → D3
the engine idles or the
transmission slips.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 3 and input clutch solenoid valveAT- 1 5 2,
AT- 1 3 0
4. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 0,
AT- 1 3 4
5. CAN communication lineAT- 9 1
6. Line pressure testAT- 5 1
7. Control valve with TCMAT- 2 1 0
OFF vehicle8. Torque converter AT- 2 4 0
9. Oil pump assemblyAT- 2 5 8
10. 3rd one-way clutchAT- 2 6 0
11. Gear systemAT- 2 2 8
12. High and low reverse clutchAT- 2 7 2
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
33When you press the
accelerator pedal and
shift speed D3 → D2
the engine idles or the
transmission slips.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 6, high and low reverse clutch sole-
noid valveAT- 1 5 6,
AT- 1 4 2
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT- 1 3 8
5. CAN communication lineAT- 9 1
6. Line pressure testAT- 5 1
7. Control valve with TCMAT- 2 1 0
OFF vehicle8. Torque converterAT- 2 4 0
9. Oil pump assemblyAT- 2 5 8
10. 3rd one-way clutchAT- 2 6 0
11. Gear systemAT- 2 2 8
12. Direct clutchAT- 2 7 4
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
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-73
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
34
Slips/Will
Not En-
gageWhen you press the
accelerator pedal and
shift speed D2 → D1
the engine idles or the
transmission slips.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. 1st one-way clutchAT-267
11. Gear systemAT-228
12. Reverse brakeAT-240
13. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to AT-
19, AT- 2 0.)AT-240
14. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 9
, AT- 2 0.)AT-240
35With selector lever in
“D” position, accelera-
tion is extremely poor.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. PNP switchAT- 9 9
6. Control cable adjustmentAT-208
7. Control valve with TCMAT-210
OFF vehicle8. Torque converterAT-240
9. Oil pump assemblyAT-258
10. 1st one-way clutchAT-267
11. Gear systemAT-228
12. Reverse brakeAT-240
13. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to AT-
19, AT- 2 0.)AT-240
14. 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
page

AT-74
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
36
Slips/Will
Not En-
gageWith selector lever in
“R” position, accelera-
tion is extremely poor.ON vehicle1. Fluid level and stateAT- 5 1
2. Line pressure testAT- 5 1
3. Accelerator pedal position sensorAT- 11 7
4. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 5 6,
AT- 1 4 2
5. CAN communication lineAT- 9 1
6. PNP switchAT- 9 9
7. Control cable adjustmentAT- 2 0 8
8. Control valve with TCMAT- 2 1 0
OFF vehicle9. Gear systemAT- 2 2 810. Output shaftAT- 2 4 0
11. Reverse brakeAT- 2 4 0
37While starting off by
accelerating in 1st, en-
gine races or slippage
occurs.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. 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
impossible 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
38While accelerating in
2nd, engine races or
slippage occurs.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. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT- 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. 3rd one-way clutchAT- 2 6 0
10. Gear systemAT- 2 2 8
11. Direct clutchAT- 2 7 4
12. 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
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-75
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
P
39
Slips/Will
Not En-
gageWhile accelerating in
3rd, engine races or
slippage occurs.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. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 5 6,
AT-142

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. High and low reverse clutchAT-272
12. Forward one- way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to AT-
19, AT- 2 0.)AT-240
13. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to AT- 1 9
, AT- 2 0.)AT-240
40While accelerating in
4th, engine races or
slippage occurs.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. ATF pressure switch 3 and input clutch solenoid valveAT- 1 5 2,
AT-130
6. Control valve with TCMAT-210
OFF vehicle7. Torque converterAT-240
8. Oil pump assemblyAT-258
9. Input clutchAT-262
10. Gear systemAT-228
11. High and low reverse clutchAT-272
12. Direct clutchAT-274
No. Items Symptom Condition Diagnostic ItemReference
page

AT-76
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
41
Slips/Will
Not En-
gage While accelerating in
5th, engine races or
slippage occurs.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. ATF pressure switch 1 and front brake solenoid valveAT- 1 5 0,
AT- 1 3 4
6. Control valve with TCMAT- 2 1 0
OFF vehicle7. Torque converterAT- 2 4 0
8. Oil pump assemblyAT- 2 5 8
9. Front brake (brake band)AT- 2 4 0
10. Input clutchAT- 2 6 2
11. Gear systemAT- 2 2 8
12. High and low reverse clutchAT- 2 7 2
42 Slips at 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
43No creep at all.
Refer to AT-172, "
Ve -
hicle Does Not Creep
Backward in "R" Posi-
tion", AT- 1 7 5 , "Vehicle
Does Not Creep For-
ward in "D" Position"
ON vehicle1. Fluid level and stateAT- 5 1
2. Line pressure testAT- 5 1
3. Accelerator pedal position sensorAT- 11 7
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 5 4,
AT- 1 3 8
5. PNP switchAT- 9 9
6. CAN communication lineAT- 9 1
7. Control cable adjustmentAT- 2 0 8
8. Control valve with TCMAT- 2 1 0
OFF vehicle9. Torque converterAT- 2 4 0
10. Oil pump assemblyAT- 2 5 8
11. 1st one-way clutchAT- 2 6 7
12. Gear systemAT- 2 2 8
13. Reverse brakeAT- 2 4 0
14. Direct clutchAT- 2 7 4
15. 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
16. 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
No. Items Symptom Condition Diagnostic ItemReference
page

AT-78
< SERVICE INFORMATION >
TROUBLE DIAGNOSIS
48
OthersShift point is low in “D”
position.ON vehicle1. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5
,
AT- 1 2 4
2. Accelerator pedal position sensorAT- 11 7
3. CAN communication lineAT- 9 1
4. Control valve with TCMAT- 2 1 0
49Judder occurs during
lock-up.ON vehicle1. Fluid level and stateAT- 5 1
2. Engine speed signalAT- 1 0 9
3. Turbine revolution sensorAT- 1 0 3
4. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 1 0 5,
AT- 1 2 4
5. Accelerator pedal position sensorAT- 11 7
6. CAN communication lineAT- 9 1
7. Torque converter clutch solenoid valveAT- 111
8. Control valve with TCMAT- 2 1 0
OFF vehicle 9. Torque converterAT- 2 4 0
50Strange noise in “R”
position.ON vehicle1. Fluid level and stateAT- 5 1
2. Engine speed signalAT- 1 0 9
3. CAN communication lineAT- 9 1
4. Control valve with TCMAT- 2 1 0
OFF vehicle5. Torque converterAT- 2 4 0
6. Oil pump assemblyAT- 2 5 8
7. Gear systemAT- 2 2 8
8. High and low reverse clutchAT- 2 7 2
9. Reverse brakeAT- 2 4 0
51Strange noise in “N”
position.ON vehicle1. Fluid level and stateAT- 5 1
2. Engine speed signalAT- 1 0 9
3. CAN communication lineAT- 9 1
4. Control valve with TCMAT- 2 1 0
OFF vehicle5. Torque converterAT- 2 4 06. Oil pump assemblyAT- 2 5 8
7. Gear systemAT- 2 2 8
52Strange noise in “D”
position.ON vehicle1. Fluid level and stateAT- 5 1
2. Engine speed signalAT- 1 0 9
3. CAN communication lineAT- 9 1
4. Control valve with TCMAT- 2 1 0
OFF vehicle5. Torque converterAT- 2 4 0
6. Oil pump assemblyAT- 2 5 8
7. Gear systemAT- 2 2 8
8. 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
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-79
< SERVICE INFORMATION >
D
E
F
G
H
I
J
K
L
MA
B
AT
N
O
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