Nissan Frontier D40. Manual - part 251

P1802 – P1804, P1809 TRANSFER CONTROL UNIT

DLN-25

< COMPONENT DIAGNOSIS >

[TRANSFER: TX15B]

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DLN

N

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Do the self-diagnostic results indicate AD converter?

YES

>> Replace transfer control unit. Refer to 

DLN-94, "Removal and Installation"

.

NO

>> Inspection End.

DLN-26

< COMPONENT DIAGNOSIS >

[TRANSFER: TX15B]

P1807 VEHICLE SPEED SENSOR (A/T)

P1807 VEHICLE SPEED SENSOR (A/T)

Description

INFOID:0000000005275420

The transmission control module (TCM) transmits the output shaft revolution signal via CAN communication to
Transfer control unit.  DTC P1807 will set when a malfunction is detected in the output shaft revolution signal
or an improper signal is input while driving.

DTC Logic

INFOID:0000000005275421

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Perform self-diagnosis.

Is DTC P1807 detected?

YES

>> Perform diagnosis procedure. Refer to 

DLN-26, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000005275422

1.

CHECK DTC WITH TCM

Perform self-diagnosis with TCM. Refer to 

DLN-17, "CONSULT-III Function (ALL MODE AWD/4WD)"

.

Is any malfunction detected by self-diagnosis?

YES

>> Check the malfunctioning system.

NO

>> GO TO 2.

2.

CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to 

DLN-55, "Reference Value"

.

Are the inspection results normal?

YES

>> GO TO 3.

NO

>> Check transfer control unit pin terminals for damage or loose connection with harness connector.

If any items are damaged, repair or replace damaged parts.

3.

CHECK DTC

Drive vehicle and then perform Self-diagnosis.
Is DTC P1807 displayed?

YES

>> Perform self-diagnosis with TCM again.

NO

>> Inspection End.

DTC

CONSULT-III

Diagnostic item is detected when...

Reference

[P1807]

VHCL SPEED SEN·AT

• Malfunction is detected in output shaft 

revolution signalthat is output from 
TCM through CAN communication.

• Improper signal is input while driving.

DLN-26

P1808 VEHICLE SPEED SENSOR (ABS)

DLN-27

< COMPONENT DIAGNOSIS >

[TRANSFER: TX15B]

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P1808 VEHICLE SPEED SENSOR (ABS)

Description

INFOID:0000000005275423

The ABS actuator and electric unit (control unit) transmits a vehicle speed signal via CAN communication to
the transfer control unit.  DTC P1808 sets when a malfunction is detected in the vehicle speed signal that is
output from the ABS actuator and electric unit (control unit) or an improper signal is input while driving.

DTC Logic

INFOID:0000000005275424

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Perform self-diagnosis.

Is DTC “P1808 displayed?

YES

>> Perform diagnosis procedure. Refer to 

DLN-27, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000005275425

1.

CHECK DTC WITH ABS ACTUATOR AND ELECTRIC UNIT (CONTROL UNIT)

Perform self-diagnosis with ABS actuator and electric unit (control unit) for specific BRC system type.

Is any malfunction detected by self-diagnosis?

YES

>> Check the malfunctioning system.

NO

>> GO TO 2.

2.

CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Refer to 

DLN-55, "Reference Value"

.

Are the inspection results normal?

YES

>> GO TO 3.

NO

>> Check transfer control unit pin terminals for damage or loose connection with harness connector.

If any items are damaged, repair or replace damaged parts.

3.

CHECK DTC

Drive vehicle and then perform Self-diagnosis.

Is DTC P1808 displayed?

YES

>> Perform self-diagnosis with ABS actuator and electric unit (control unit) for specific BRC system

type.

NO

>> Inspection End.

DTC

CONSULT-III

Diagnostic item is detected when...

Reference

[P1808]

VHCL SPEED SEN·ABS

• Malfunction is detected in vehicle 

speed signal that is output from ABS 
actuator and electric unit (control unit) 
through CAN communication.

• Improper signal is input while driving.

DLN-27

DLN-28

< COMPONENT DIAGNOSIS >

[TRANSFER: TX15B]

P1810 4 LO SWITCH

P1810 4 LO SWITCH

Description

INFOID:0000000005275426

The 4LO switch detects that the transfer case is in 4LO range.  DTC P1810 will set when an improper signal
from the 4LO switch is input due to an open or short circuit.

DTC Logic

INFOID:0000000005275427

DTC DETECTION LOGIC

DTC CONFIRMATION PROCEDURE

1.

DTC CONFIRMATION PROCEDURE

1.

Turn ignition switch ON.

2.

Perform self-diagnosis.

Is DTC P1810 displayed?

YES

>> Perform diagnosis procedure. Refer to 

DLN-28, "Diagnosis Procedure"

.

NO

>> Inspection End.

Diagnosis Procedure

INFOID:0000000005275428

Regarding Wiring Diagram information, refer to 

DLN-60, "Wiring Diagram"

.

1.

CHECK 4LO POSITION SWITCH SIGNAL

With CONSULT-III

1.

Start engine.

2.

Select “DATA MONITOR” mode for “ALL MODE AWD/4WD” with CONSULT-III.

3.

Read out the value of “4L POSI SW”.

Without CONSULT-III

1.

Start engine.

2.

Check voltage between transfer control unit harness connector
terminal and ground.

Are the inspection results normal?

DTC

CONSULT-III

Diagnostic item is detected when...

Reference

[P1810]

4L POSI SW TF

Improper signal from 4LO switch is input 
due to open or short circuit.

DLN-28

Condition

Display value

• Vehicle stopped
• Engine running
• A/T selector lever “N” position
• Brake pedal depressed

4WD shift switch: 4LO

ON

Except the above

OFF

Connector

Terminal

Condition

Voltage 

(Approx.)

M152

 24 - 

Ground

• Vehicle stopped
• Engine running
• A/T selector lever 

“N” position

• Brake pedal de-

pressed

4WD shift switch: 4LO

0V

Except the above

Battery 
voltage

SDIA3363E