2004 INFINITI QX56 clutch

AT-58
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Inspections Before Trouble DiagnosisUCS002CX
A/T FLUID CHECK
Fluid Leakage and Fluid Level Check

Inspect for fluid leakage and check the fluid level. Refer to AT - 1 3 , "Checking A/T Fluid" .
Fluid Condition Check
Inspect the fluid condition.
STALL TEST
Stall Test Procedure
1. Inspect the amount of engine oil. Replenish the engine oil if necessary.
2. Drive for about 10 minutes to warm up the vehicle so that the A/
T fluid temperature is 50 to 80°C (122 to 176°F). Inspect the
amount of ATF. Replenish if necessary.
3. Securely engage the parking brake so that the tires do not turn.
4. Engine start, apply foot brake, and place selector lever in “D”
position.
5. While holding down the foot brake, gradually press down the
accelerator pedal.
6. Quickly read off the stall speed, then quickly remove your foot
from the accelerator pedal.
CAUTION:
Do not hold down the accelerator pedal for more than 5 sec-
onds during this test.
7. Move the selector lever to the “N” position.
8. Cool down the ATF.
Fluid condition Conceivable Cause Required Operation
Varnished (viscous
varnish state)Clutch, brake
scorchedReplace the ATF and check the A/T
main unit and the vehicle for mal-
functions (wire harnesses, cooler
pipes, etc.)
Milky white or
cloudyWater in the fluidReplace the ATF and check for
places where water is getting in.
Large amount of
metal powder mixed
inUnusual wear of
sliding parts within
A/TReplace the ATF and check for
improper operation of the A/T.
SAT6 3 8A
SAT6 4 7B
SCIA1224E
SAT5 1 4G

TROUBLE DIAGNOSIS
AT-59
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
CAUTION:
Run the engine at idle for at least one minute.
Judgement of Stall Test
O: Stall speed within standard value position
H: Stall speed higher than standard value
L: Stall speed lower than standard value
Stall test standard value position
LINE PRESSURE TEST
Line Pressure Test Port
Line Pressure Test Procedure
1. Inspect the amount of engine oil and replenish if necessary.
2. Drive the car for about 10 minutes to warm it up so that the ATF reaches in range of 50 to 80°C (122 to
176°F), then inspect the amount of ATF and replenish if necessary.
NOTE:
The automatic fluid temperature rises in range of 50 to 80°C (122 to 176°F) during 10 minutes of
driving.Stall speed: 2,500 - 2,800 rpm
Selector lever position
Expected problem location
DR
Stall rotation HO

Forward brake

Forward one-way clutch

1st one-way clutch

3rd one-way clutch
OH

Reverse brake
LL

Engine and torque converter one-way clutch
HH

Line pressure low
Does not shift-up D position 1 → 2 Slipping in 2nd, 3rd, 4th gears Direct clutch slippage
Does not shift-up D position 2 → 3 Slipping in 3rd, 4th, 5th gears High & low reverse clutch slippage
Does not shift-up D position 3 → 4 Slipping in 4th, 5th gears Input clutch slippage
Does not shift-up D position 4 → 5 Slipping in 5th gear Front brake slippage
SCIA1291E

AT-68
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
Symptom ChartUCS002D6

The diagnostics item numbers show the sequence for inspection. Inspect in order from item 1.

Overhaul and inspect inside the A/T only if A/T fluid condition is NG. Refer to AT-58, "Fluid Condi-
tion Check" .
No. Items Symptom Condition Diagnostic ItemReference
page
1
Shift
ShockLarge shock. (“N” →“
D” position)
Refer to AT-195,
"Large Shock (“N” to
“D” Position)" .ON vehicle1. Engine idle speedEC-32
2. Engine speed signalAT - 11 5
3. Accelerator pedal position sensorAT- 1 2 9
4. Control cable adjustmentAT- 2 3 4
5. ATF temperature sensorAT- 1 3 1
6. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1
7. CAN communication lineAT- 1 0 3
8. Fluid level and stateAT-5 8
9. Line pressure testAT-5 9
10. Control valve with TCMAT- 2 4 2
OFF vehicle11. 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
2Shock is too large
when changing D1 →
D
2 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
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. Engine speed signalAT - 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT-5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. Direct clutchAT- 3 0 7
3Shock is too large
when changing D2 →
D
3 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
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. Engine speed signalAT - 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT-5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. High and low reverse clutchAT- 3 0 5

TROUBLE DIAGNOSIS
AT-69
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
4
Shift
ShockShock is too large
when changing D3 →
D
4 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. ATF pressure switch 3 and input clutch solenoid valveAT- 1 7 8,
AT- 1 4 5
4. CAN communication lineAT- 1 0 3
5. Engine speed signalAT- 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT- 5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle 10. Input clutchAT- 2 9 5
5Shock is too large
when changing D4 →
D
5 .ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. ATF pressure switch 1 and front brake solenoid valveAT- 1 7 5,
AT- 1 5 1

4. CAN communication lineAT- 1 0 3
5. Engine speed signalAT- 11 5
6. Turbine revolution sensorAT- 1 3 4
7. Vehicle speed sensor A/T and vehicle speed sensor MTRAT- 11 2,
AT- 1 3 6
8. Fluid level and stateAT- 5 8
9. Control valve with TCMAT- 2 4 1
OFF vehicle10. Front brake (brake band)AT- 2 6 111. Input clutchAT- 2 9 5
6Shock is too large for
downshift when accel-
erator pedal is
pressed.ON vehicle1. Accelerator pedal position sensorAT- 1 2 9
2. Control cable adjustmentAT- 2 3 4
3. CAN communication lineAT- 1 0 3
4. Engine speed signalAT- 11 5
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
No. Items Symptom Condition Diagnostic ItemReference
page

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
page

TROUBLE DIAGNOSIS
AT-71
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX5610
No Up
ShiftGear does not change
from D
1 → D2 .
Refer to AT- 2 0 6 , "
A/T
Does Not Shift: D1 →
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. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle 7. Direct clutchAT- 3 0 7
11Gear does not change
from D2 → D3 .
Refer toAT- 2 0 8 , "
A/T
Does Not Shift: D2 →
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. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle 7. High and low reverse clutchAT- 3 0 5
12Gear does not change
from D
3 → D4 .
Refer toAT- 2 1 0 , "
A/T
Does Not Shift: D3 →
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. Line pressure testAT- 5 9
6. CAN communication lineAT- 1 0 3
7. Control valve with TCMAT- 2 4 1
OFF vehicle 8. Input clutchAT- 2 9 5
13Gear does not change
from D
4 → D5 .
Refer toAT- 2 1 3 , "
A/T
Does Not Shift: D4 →
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. Turbine revolution sensorAT- 1 3 4
6. Line pressure testAT- 5 9
7. CAN communication lineAT- 1 0 3
8. Control valve with TCMAT- 2 4 1
OFF vehicle9. Front brake (brake band)AT- 2 7 310. Input clutchAT- 2 9 5
No. Items Symptom Condition Diagnostic ItemReference
page

AT-72
TROUBLE DIAGNOSIS
Revision: August 20072004 QX56
14
No Down
ShiftIn “D” range, does not
downshift to 4th gear.
Refer to AT-221, "A/T
Does Not Shift: 5th
gear → 4th 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. 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. Front brake (brake band)AT- 2 7 39. Input clutchAT- 2 9 5
15In “D” range, does not
downshift to 3rd gear.
Refer toAT- 2 2 4 , "A/T
Does Not Shift: 4th
gear → 3rd 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 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 vehicle 8. Input clutchAT- 2 9 5
16In “D” range, does not
downshift to 2nd gear.
Refer toAT- 2 2 5 , "A/T
Does Not Shift: 3rd
gear → 2nd 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 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 vehicle 7. High and low reverse clutchAT- 3 0 5
17In “D” range, does not
downshift to 1st gear.
Refer toAT- 2 2 7 , "A/T
Does Not Shift: 2nd
gear → 1st 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 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 vehicle 7. Direct clutchAT- 3 0 7
No. Items Symptom Condition Diagnostic ItemReference
page

TROUBLE DIAGNOSIS
AT-73
D
E
F
G
H
I
J
K
L
MA
B
AT
Revision: August 20072004 QX56
18
Slips/Will
Not
engageWhen “D” position,
remains in 1st 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. Direct clutch solenoid valveAT- 1 5 7
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. 3rd one-way clutchAT- 2 9 2
8. 1st one-way clutchAT- 3 0 0
9. Gear systemAT- 2 6 1
10. Reverse brakeAT- 2 7 3
11. 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
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
19When “D” position,
remains in 2nd gear.ON vehicle1. Fluid level and stateAT- 5 8
2. Vehicle speed sensor A/T and vehicle speed sensor MTR AT- 11 2 ,
AT- 1 3 6
3. Low coast brake solenoid valveAT- 1 6 9
4. Line pressure testAT- 5 9
5. CAN communication lineAT- 1 0 3
6. Control valve with TCMAT- 2 4 1
OFF vehicle7. 3rd one-way clutchAT- 2 9 2
8. Gear systemAT- 2 6 1
9. Direct clutchAT- 3 0 7
10. 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