Infiniti M35/M45 Y50. Manual — part 38

TROUBLE DIAGNOSIS

AT-75

D

E

F

G

H

I

J

K

L

M

A

B

AT

30

Slips/Will
Not
Engage

No shock at all or the
clutch slips when
vehicle changes
speed D

4

→

D

5

or

M

4

→

M

5

.

ON vehicle

1. A/T fluid level and state

AT-53

2. Vehicle speed sensor·A/T and vehicle speed sensor·MTR

AT-119

,

AT-140

3. ATF pressure switch 1 and front brake solenoid valve

AT-172

,

AT-151

4. ATF pressure switch 5 and direct clutch solenoid valve

AT-176

,

AT-155

5. CAN communication line

AT-105

6. Line pressure test

AT-55

7. Control valve with TCM

AT-236

OFF vehicle

8. Torque converter

AT-301

9. Oil pump assembly

AT-322

10. Front brake (brake band)

AT-301

11. Input clutch

AT-327

12. Gear system

AT-281

13. High and low reverse clutch

AT-339

31

When you press the
accelerator pedal and
shift speed D

5

→

D

4

or M

5

→

M

4

the

engine idles or the A/
T slips.

ON vehicle

1. A/T fluid level and state

AT-53

2. Vehicle speed sensor·A/T and vehicle speed sensor·MTR

AT-119

,

AT-140

3. ATF pressure switch 1 and front brake solenoid valve

AT-172

,

AT-151

4. ATF pressure switch 5 and direct clutch solenoid valve

AT-176

,

AT-155

5. CAN communication line

AT-105

6. Line pressure test

AT-55

7. Control valve with TCM

AT-236

OFF vehicle

8. Torque converter

AT-301

9. Oil pump assembly

AT-322

10. Input clutch

AT-327

11. Gear system

AT-281

12. High and low reverse clutch

AT-339

13. Direct clutch

AT-341

No.

Item

Symptom

Condition

Diagnostic Item

Reference

page

AT-76

TROUBLE DIAGNOSIS

32

Slips/Will
Not
Engage

When you press the
accelerator pedal and
shift speed D

4

→

D

3

or M

4

→

M

3

the

engine idles or the A/
T slips.

ON vehicle

1. A/T fluid level and state

AT-53

2. Vehicle speed sensor·A/T and vehicle speed sensor·MTR

AT-119

,

AT-140

3. ATF pressure switch 3 and input clutch solenoid valve

AT-174

,

AT-147

4. ATF pressure switch 1 and front brake solenoid valve

AT-172

,

AT-151

5. CAN communication line

AT-105

6. Line pressure test

AT-55

7. Control valve with TCM

AT-236

OFF vehicle

8. Torque converter

AT-301

9. Oil pump assembly

AT-322

10. 3rd one-way clutch

AT-325

11. Gear system

AT-281

12. High and low reverse clutch

AT-339

13. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to

AT-17, "Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18, "Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19, "Cross-Sectional View (AWD Models)"

.)

AT-301

14. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to

AT-17,

"Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18,

"Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19,

"Cross-Sectional View (AWD Models)"

.)

AT-301

33

When you press the
accelerator pedal and
shift speed D

3

→

D

2

or M

3

→

M

2

the

engine idles or the A/
T slips.

ON vehicle

1. A/T fluid level and state

AT-53

2. Vehicle speed sensor·A/T and vehicle speed sensor·MTR

AT-119

,

AT-140

3. ATF pressure switch 6, high and low reverse clutch sole-
noid valve

AT-178

,

AT-159

4. ATF pressure switch 5 and direct clutch solenoid valve

AT-176

,

AT-155

5. CAN communication line

AT-105

6. Line pressure test

AT-55

7. Control valve with TCM

AT-236

OFF vehicle

8. Torque converter

AT-301

9. Oil pump assembly

AT-322

10. 3rd one-way clutch

AT-325

11. Gear system

12. Direct clutch

AT-341

13. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to

AT-17,

"Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18,

"Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19,

"Cross-Sectional View (AWD Models)"

.)

AT-301

No.

Item

Symptom

Condition

Diagnostic Item

Reference

page

TROUBLE DIAGNOSIS

AT-77

D

E

F

G

H

I

J

K

L

M

A

B

AT

34

Slips/Will
Not
Engage

When you press the
accelerator pedal and
shift speed D

2

→

D

1

or M

2

→

M

1

the

engine idles or the A/
T slips.

ON vehicle

1. A/T fluid level and state

AT-53

2. Vehicle speed sensor·A/T and vehicle speed sensor·MTR

AT-119

,

AT-140

3. ATF pressure switch 5 and direct clutch solenoid valve

AT-176

,

AT-155

4. CAN communication line

AT-105

5. Line pressure test

AT-55

6. Control valve with TCM

AT-236

OFF vehicle

7. Torque converter

AT-301

8. Oil pump assembly

AT-322

9. 3rd one-way clutch

AT-325

10. 1st one-way clutch

AT-333

11. Gear system

AT-281

12. Reverse brake

AT-301

13. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to

AT-17, "Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18, "Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19, "Cross-Sectional View (AWD Models)"

.)

AT-301

14. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to

AT-17,

"Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18,

"Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19,

"Cross-Sectional View (AWD Models)"

.)

AT-301

35

With selector lever in
“D” position, accelera-
tion is extremely poor.

ON vehicle

1. A/T fluid level and state

AT-53

2. Line pressure test

AT-55

3. Accelerator pedal position sensor

AT-132

4. CAN communication line

AT-105

5. PNP switch

AT-113

6. A/T position

AT-227

7. Control valve with TCM

AT-236

OFF vehicle

8. Torque converter

AT-301

9. Oil pump assembly

AT-322

10. 1st one-way clutch

AT-333

11. Gear system

AT-281

12. Reverse brake

AT-301

13. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to

AT-17, "Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18, "Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19, "Cross-Sectional View (AWD Models)"

.)

AT-301

14. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to

AT-17,

"Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18,

"Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19,

"Cross-Sectional View (AWD Models)"

.)

AT-301

No.

Item

Symptom

Condition

Diagnostic Item

Reference

page

AT-78

TROUBLE DIAGNOSIS

36

Slips/Will
Not
Engage

With selector lever in
“R” position, accelera-
tion is extremely poor.

ON vehicle

1. A/T fluid level and state

AT-53

2. Line pressure test

AT-55

3. Accelerator pedal position sensor

AT-132

4. ATF pressure switch 6, high and low reverse clutch sole-
noid valve

AT-178

,

AT-159

5. CAN communication line

AT-105

6. PNP switch

AT-113

7. A/T position

AT-227

8. Control valve with TCM

AT-236

OFF vehicle

9. Gear system

AT-281

10. Output shaft

AT-301

11. Reverse brake

AT-301

37

While starting off by
accelerating in 1st,
engine races or slip-
page occurs.

ON vehicle

1. A/T fluid level and state

AT-53

2. Line pressure test

AT-55

3. Accelerator pedal position sensor

AT-132

4. CAN communication line

AT-105

5. Control valve with TCM

AT-236

OFF vehicle

6. Torque converter

AT-301

7. Oil pump assembly

AT-322

8. 3rd one-way clutch

AT-325

9. 1st one-way clutch

AT-333

10. Gear system

AT-281

11. Reverse brake

AT-301

12. Forward one-way clutch (Parts behind drum support is
impossible to perform inspection by disassembly. Refer to

AT-17, "Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18, "Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19, "Cross-Sectional View (AWD Models)"

.)

AT-301

13. Forward brake (Parts behind drum support is impossible
to perform inspection by disassembly. Refer to

AT-17,

"Cross-Sectional View (VQ35DE Models for 2WD)"

,

AT-18,

"Cross-Sectional View (VK45DE Models for 2WD)"

or

AT-19,

"Cross-Sectional View (AWD Models)"

.)

AT-301

No.

Item

Symptom

Condition

Diagnostic Item

Reference

page