Toyota Tundra Service Manual: 4WD Control Switch Circuit

WIRING DIAGRAM

PROCEDURE

1.

CONFIRM PROBLEM SYMPTOM

(a) Confirm the problem symptoms.

Result

Result

Proceed to

The 4HI and 4LO indicator lights are not illuminated

A

The 4HI indicator light is illuminated and the 4LO indicator light is not illuminated

B

The 4HI indicator light is not illuminated and the 4LO indicator light is illuminated

C

B

GO TO STEP 5

C

GO TO STEP 6

A

2.

CHECK 4HI INDICATOR LIGHT

(a) Turn the ignition switch to ON.

(b) Move the shift lever to N.

(c) Turn the transfer position switch to 4H.

(d) Check the 4HI indicator light.

Result

Result

Proceed to

The 4HI indicator light is blinking or illuminated

A

The 4HI indicator light is not illuminated

B

A

END

B

3.

CHECK FOR DTC

(a) Turn the transfer position switch to 4L.

(b) Check if DTC P279E is output after 60 seconds elapse (See page ).

Result

Result

Proceed to

DTC P279E is not output

A

DTC P279E is output

B

B

REPAIR CIRCUIT INDICATED BY OUTPUT CODE

A

4.

CHECK CAN COMMUNICATION LINE

(a) Select "Bus Check" from the System Selection Menu screen, and follow the prompts on the screen to inspect the CAN Bus (See page ).

OK:

"Bus Check" indicates no malfunctions in CAN communication.

OK

GO TO METER / GAUGE SYSTEM (HOW TO PROCEED WITHTROUBLESHOOTING)

NG

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITHTROUBLESHOOTING)

5.

CHECK 4HI INDICATOR LIGHT

(a) Turn the ignition switch to ON.

(b) Move the shift lever to N.

(c) Turn the transfer position switch to 2WD.

(d) Turn the transfer position switch to 2WD.

Result

Result

Proceed to

The 4HI indicator light is blinking or not illuminated

A

The 4HI indicator light is illuminated

B

A

END

B

GO TO DTC P279E

6.

CHECK 4LO INDICATOR LIGHT

(a) Turn the ignition switch to ON.

(b) Move the shift lever to N.

(c) Turn the transfer position switch to 4H.

(d) Check the 4LO indicator light.

Result

Result

Proceed to

The 4LO indicator light is blinking or not illuminated

A

The 4LO indicator light is illuminated

B

A

END

B

7.

CHECK FOR DTC

(a) Turn the transfer position switch to 2WD.

(b) Check if DTC P279E is output after 60 seconds elapse (See page ).

Result

Result

Proceed to

DTC P279E is not output

A

DTC P279E is output

B

A

GO TO CAN COMMUNICATION SYSTEM (HOW TO PROCEED WITHTROUBLESHOOTING)

B

REPAIR CIRCUIT INDICATED BY OUTPUT CODE

    Touch Select 2-4 And High-low System

    Diagnosis System

    See More:

    Toyota Tundra Service Manual > Sfi System: Exhaust Gas Recirculation Flow Insufficient Detected (P0401)
    DESCRIPTION Based on the driving conditions, the ECM regulates the volume of exhaust gas that is recirculated to the engine's combustion chambers and thus lowers the combustion temperature to reduce NOx emissions. The ECM monitors signals such as engine speed, coolant temperature, electric load, and ...

    Toyota Tundra Owners Manual

    Toyota Tundra Service Manual

    © 2021 Copyright www.ttundra.com
    0.0184