2004 INFINITI QX56 low oil pressure

TROUBLE DIAGNOSIS
AT-75
D
E
F
G
H
I
J
K
L
MA
B
AT
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
page

TROUBLE DIAGNOSIS
AT-77
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
28
Slips/Will
Not
engageNo shock at all or the
clutch slips when
vehicle changes
speed D
2 → D3 .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 6, high and low reverse clutch sole-
noid valveAT- 1 8 4,
AT- 1 6 3
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. High and low reverse clutchAT- 3 0 5
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
29No shock at all or the
clutch slips when
vehicle changes
speed D
3 → D4 .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 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5

4. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5
,
AT- 1 5 1
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT- 5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 3
9. Oil pump assemblyAT- 2 9 0
10. Input clutchAT- 2 9 5
11. Gear systemAT- 2 6 1
12. High and low reverse clutchAT- 3 0 5
13. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

AT-78
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
30
Slips/Will
Not
engageNo shock at all or the
clutch slips when
vehicle changes
speed D
4 → D5 .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. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT-5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 3
9. Oil pump assemblyAT- 2 9 0
10. Front brake (brake band)AT- 2 7 3
11. Input clutchAT- 2 9 5
12. Gear systemAT- 2 6 1
13. High and low reverse clutchAT- 3 0 5
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 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. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT-5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 3
9. Oil pump assemblyAT- 2 9 0
10. Input clutchAT- 2 9 5
11. Gear systemAT- 2 6 1
12. High and low reverse clutchAT- 3 0 5
13. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-79
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
32
Slips/Will
Not
engageWhen you press the
accelerator pedal and
shift speed D4 → D3
the engine idles or the
transmission slips.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 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
4. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT- 5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converter AT- 2 7 3
9. Oil pump assemblyAT- 2 9 0
10. 3rd one-way clutchAT- 2 9 2
11. Gear systemAT- 2 6 1
12. High and low reverse clutchAT- 3 0 5
13. 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
14. 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
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 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
3. ATF pressure switch 6, high and low reverse clutch sole-
noid valveAT- 1 8 4,
AT- 1 6 3
4. ATF pressure switch 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
5. CAN communication lineAT- 1 0 3
6. Line pressure testAT- 5 9
7. Control valve with TCMAT- 2 4 1
OFF vehicle8. Torque converterAT- 2 7 3
9. Oil pump assemblyAT- 2 9 0
10. 3rd one-way clutchAT- 2 9 2
11. Gear systemAT- 2 6 1
12. Direct clutchAT- 3 0 7
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
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-81
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
36
Slips/Will
Not
EngageWith selector lever in
“R” position, accelera-
tion is extremely poor.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 6, high and low reverse clutch sole-
noid valveAT- 1 8 4,
AT- 1 6 3
5. CAN communication lineAT- 1 0 3
6. PNP switchAT- 1 0 9
7. Control cable adjustmentAT- 2 3 4
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Gear systemAT- 2 6 110. Output shaftAT- 2 7 3
11. Reverse brakeAT- 2 7 3
37While starting off by
accelerating in 1st,
engine races or slip-
page 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. 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
38While accelerating in
2nd, 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 5 and direct clutch solenoid valveAT- 1 8 1,
AT- 1 5 7
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
page

AT-82
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
39
Slips/Will
Not
EngageWhile accelerating in
3rd, 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 6, high and low reverse clutch sole-
noid valveAT- 1 8 4,
AT- 1 6 3

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. High and low reverse clutchAT- 3 0 5
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
40While accelerating in
4th, 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 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. Torque converterAT- 2 7 3
8. Oil pump assemblyAT- 2 9 0
9. Input clutchAT- 2 9 5
10. Gear systemAT- 2 6 1
11. High and low reverse clutchAT- 3 0 5
12. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-83
D
E
F
G
H
I
J
K
L
MA
B
AT
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
page

TROUBLE DIAGNOSIS
AT-87
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
56
OthersMaximum speed low.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. Direct clutch solenoid valveAT- 1 5 7
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. Torque converterAT- 2 7 3
8. Oil pump assemblyAT- 2 9 0
9. Input clutchAT- 2 9 5
10. Gear systemAT- 2 6 1
11. High and low reverse clutchAT- 3 0 5
12. Direct clutchAT- 3 0 7
13. 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
14 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
57Extremely large
creep.ON vehicle1. Engine idle speed EC-32

2. CAN communication lineAT- 1 0 3
3. ATF pressure switch 5AT- 1 8 1
OFF vehicle 4. Torque converterAT- 2 7 3
58With selector lever in
“P” position, vehicle
does not enter parking
condition or, with
selector lever in
another position, park-
ing condition is not
cancelled.
Refer to AT- 1 9 3 , "
In
“P” Position, Vehicle
Moves When Pushed"
.ON vehicle1. PNP switchAT- 1 0 9
2. Control cable adjustmentAT- 2 3 4
3. Parking pawl componentsAT- 2 6 1
59Vehicle runs with
transmission in “P”
position.ON vehicle1. PNP switchAT- 1 0 9
2. Fluid level and stateAT- 5 8
3. Control cable adjustmentAT- 2 3 4
4. Control valve with TCMAT- 2 4 1
5. Parking pawl componentsAT- 2 6 1
OFF vehicle 6. Gear systemAT- 2 6 1
No. Items Symptom Condition Diagnostic ItemReference
page