Nissan Altima L32. Instruction — part 1454

TM-160

< COMPONENT DIAGNOSIS >

[CVT: RE0F09B]

P0840 TRANSMISSION FLUID PRESSURE SENSOR A (SEC PRESSURE SEN-

SOR)

P0840 TRANSMISSION FLUID PRESSURE SENSOR A (SEC PRESSURE
SENSOR)

Description

INFOID:0000000004201724

The transmission fluid pressure sensor A (secondary pressure sensor) detects secondary pressure of CVT

and sends TCM the signal.

DTC Logic

INFOID:0000000004201725

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

NOTE:

If “DTC CONFIRMATION PROCEDURE” has been previously performed, always turn ignition switch OFF.

Then wait at least 10 seconds before performing the next test.

1.

CHECK DTC DETECTION

With CONSULT-III

1. Turn ignition switch ON.

2. Select “DATA MONITOR”.

3. Make sure that output voltage of CVT fluid temperature sensor is within the range below.

4. Start engine and wait for at least 5 consecutive seconds.

With GST

Follow the procedure “With CONSULT-III”.
Is “P0840 TR PRS SENS/A CIRC” detected?

YES

>> Go to

TM-160, "Diagnosis Procedure"

.

NO

>> Check intermittent incident. Refer to

GI-42, "Intermittent Incident"

.

Diagnosis Procedure

INFOID:0000000004201726

1.

CHECK INPUT SIGNAL

1. Start engine.

2. Check voltage between TCM harness connector F16 terminal

15 and ground.

3. Turn ignition switch OFF.
Is the inspection result normal?

YES

>> GO TO 8.

NO

>> GO TO 2.

DTC

Item

(CONSULT-III screen term)

Malfunction is detected when...

Possible cause

P0840

TR PRS SENS/A CIRC

Signal voltage of the transmission fluid pres-
sure sensor A (secondary pressure sensor)
is too high or too low while driving.

• Harness or connectors

(Sensor circuit is open or shorted.)

• Transmission fluid pressure sensor A

(secondary pressure sensor)

ATF TEMP SEN

: 1.0 – 2.0 V

If out of range, drive the vehicle to decrease the voltage (warm up the fluid) or stop engine to increase the voltage (cool
down the fluid)

TCM harness connec-

tor

Ground

Condition

Voltage

(Approx.)

Connec-

tor

Terminal

F16

15

“N” position idle

1.0 V

JPDIA0984ZZ

P0840 TRANSMISSION FLUID PRESSURE SENSOR A (SEC PRESSURE SEN-

SOR)

TM-161

< COMPONENT DIAGNOSIS >

[CVT: RE0F09B]

C

E

F

G

H

I

J

K

L

M

A

B

TM

N

O

P

2.

CHECK POWER AND SENSOR GROUND

1. Turn ignition switch ON.

2. Check voltage between TCM harness connector F16 terminal

25 and 26.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> GO TO 5.

3.

CHECK HARNESS BETWEEN TCM AND CVT UNIT [TRANSMISSION FLUID PRESSURE SENSOR A

(SECONDARY PRESSURE SENSOR)] (PART 1)

1. Turn ignition switch OFF.

2. Disconnect TCM harness connector and CVT unit harness con-

nector.

3. Check continuity between TCM harness connector F16 (A) ter-

minal 15 and CVT unit harness connector F46 (B) terminal 23.

Is the inspection result normal?

YES

>> GO TO 4.

NO

>> Repair or replace damaged parts.

4.

CHECK HARNESS BETWEEN TCM AND CVT UNIT [TRANSMISSION FLUID PRESSURE SENSOR A

(SECONDARY PRESSURE SENSOR)] (PART 2)

Check continuity between TCM harness connector F16 terminal 15

and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair or replace damaged parts.

5.

CHECK HARNESS BETWEEN TCM AND CVT UNIT (SENSOR POWER AND SENSOR GROUND) (PART

1)

1. Turn ignition switch OFF.

2. Disconnect TCM harness connector and CVT unit harness con-

nector.

3. Check continuity between TCM harness connector F16 (A) ter-

minal 25, 26 and CVT unit harness connector F46 (B) terminal

19, 20.

Is the inspection result normal?

TCM harness connector

Voltage (Approx.)

Connector

Terminal

F16

25

26

5.0 V

AWDIA0132ZZ

TCM harness connector

CVT unit harness connector

Continuity

Connector

Terminal

Connector

Terminal

F16 (A)

15

F46 (B)

23

Existed

AWDIA0133ZZ

TCM harness connector

Ground

Continuity

Connector

Terminal

F16

15

Not existed

AWDIA0134ZZ

TCM harness connector

CVT unit harness connector

Continuity

Connector

Terminal

Connector

Terminal

F16 (A)

25

F46 (B)

19

Existed

26

20

AWDIA0135ZZ

TM-162

< COMPONENT DIAGNOSIS >

[CVT: RE0F09B]

P0840 TRANSMISSION FLUID PRESSURE SENSOR A (SEC PRESSURE SEN-

SOR)

YES

>> GO TO 6.

NO

>> Repair or replace damaged parts.

6.

CHECK HARNESS BETWEEN TCM AND CVT UNIT (SENSOR POWER AND SENSOR GROUND) (PART

2)
Check continuity between TCM harness connector F16 terminal 25,

26 and ground.

Is the inspection result normal?

YES

>> GO TO 7.

NO

>> Repair or replace damaged parts.

7.

CHECK TCM

1. Replace same type TCM. Refer to

TM-254, "Exploded View"

.

2. Connect each connector.

3. Perform “DTC CONFIRMATION PROCEDURE”. Refer to

TM-160, "DTC Logic"

.

Is “P0840 TR PRS SENS/A CIRC” detected?

YES

>> Replace transaxle assembly. Refer to

TM-259, "Exploded View"

.

NO

>> Replace TCM. Refer to

TM-254, "Exploded View"

.

8.

DETECT MALFUNCTIONING ITEMS

Check TCM connector pin terminals for damage or loose connection with harness connector.
Is the inspection result normal?

YES

>> Replace TCM. Refer to

TM-254, "Exploded View"

.

NO

>> Repair or replace damaged parts.

TCM harness connector

Ground

Continuity

Connector

Terminal

F16

25

Not existed

26

AWDIA0136ZZ

P0841 PRESSURE SENSOR FUNCTION

TM-163

< COMPONENT DIAGNOSIS >

[CVT: RE0F09B]

C

E

F

G

H

I

J

K

L

M

A

B

TM

N

O

P

P0841 PRESSURE SENSOR FUNCTION

Description

INFOID:0000000004201727

Using the engine load (throttle position), the primary pulley revolution speed, and the secondary pulley revolu-

tion speed as input signal, TCM changes the operating pressure of the primary pulley and the secondary pul-

ley and changes the groove width of the pulley to control the gear ratio.

DTC Logic

INFOID:0000000004201728

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

CAUTION:

Always drive vehicle at a safe speed.

NOTE:

If “DTC CONFIRMATION PROCEDURE” has been previously performed, always turn ignition switch OFF.

Then wait at least 10 seconds before performing the next test.

1.

CHECK DTC DETECTION

With CONSULT-III

1. Turn ignition switch ON.

2. Select “DATA MONITOR”.

3. Start engine and maintain the following conditions for at least 12 consecutive seconds.

Is “P0841 PRESS SEN/FNCTN” detected?

YES

>> Go to

TM-163, "Diagnosis Procedure"

.

NO

>> Check intermittent incident. Refer to

GI-42, "Intermittent Incident"

.

Diagnosis Procedure

INFOID:0000000004201729

1.

CHECK LINE PRESSURE

Perform line pressure test. Refer to

TM-247, "Inspection and Judgment"

.

Is the inspection result normal?

YES

>> .GO TO 2.

NO

>> Repair or replace damaged parts. Refer to

TM-247, "Inspection and Judgment"

.

2.

CHECK TRANSMISSION FLUID PRESSURE SENSOR A (SECONDARY PRESSURE SENSOR) SYS-

TEM

Check transmission fluid pressure sensor A (secondary pressure sensor) system. Refer to

TM-160, "Descrip-

tion"

.

Is the inspection result normal?

YES

>> GO TO 3.

NO

>> Repair or replace damaged parts.

3.

CHECK TRANSMISSION FLUID PRESSURE SENSOR B (PRIMARY PRESSURE SENSOR) SYSTEM

Check transmission fluid pressure sensor B (primary pressure sensor) system. Refer to

TM-166, "Descrip-

tion"

.

DTC

Item

(CONSULT-III screen term)

Malfunction is detected when...

Possible cause

P0841

PRESS SEN/FNCTN

Correlation between the values of the trans-
mission fluid pressure sensor A (secondary
pressure sensor) and the transmission fluid
pressure sensor B (primary pressure sen-
sor) is out of specification.

• Harness or connectors

(Sensor circuit is open or shorted.)

• Transmission fluid pressure sensor A

(secondary pressure sensor)

• Transmission fluid pressure sensor B (pri-

mary pressure sensor)

VEHICLE SPEED

: 40 km/h (25 MPH) or more

RANGE

: “D” position