Toyota Tacoma 2015-2018 Service Manual: 4WD Control Switch Circuit

Toyota Tacoma 2015-2018 Service Manual / Vf2cm Transfer / Touch Select 2-4 And High-low System / 4WD Control Switch Circuit

WIRING DIAGRAM

PROCEDURE

1.	CONFIRM PROBLEM SYMPTOM

(a) Confirm the problem symptoms.

Result

Result	Proceed to
The 4WD indicator light (green) and 4LO indicator light remain off	A
The 4WD indicator light (green) remains illuminated, and the 4LO indicator light remains off	B
The 4WD indicator light (green) and 4LO indicator light remain illuminated	C

GO TO STEP 6

GO TO STEP 7

2.	CHECK 4WD INDICATOR LIGHT (GREEN)

(a) Turn the ignition switch to ON.

(b) for Automatic Transmission:

Move the shift lever to N.

for Manual Transmission:

Depress the clutch pedal.

(d) Wait for 60 seconds.

(e) Check the 4WD indicator light (green).

Result

Result	Proceed to
The 4WD indicator light (green) blinks*1 or illuminates	A
The 4WD indicator light (green) rapidly blinks*2 or remains off	B

*1 (Blinking): Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)
*2 (Rapidly blinking): Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)

END

3.	CHECK FOR DTC

(a) Turn the transfer position switch to L4.

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

Result

Result	Proceed to
DTC P279E is not output	A
DTC P279E is output	B

REPAIR CIRCUIT INDICATED BY OUTPUT CODE

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: OK: ).

OK:

"Bus Check" indicates no malfunctions in CAN communication.

CHECK CAN COMMUNICATION SYSTEM

5.	CHECK TRANSFER POSITION SWITCH

(a) Remove the transfer position switch with its connector still connected.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
F15-2 (2-4) - Body ground	Ignition switch ON 2WD position	Below 1.5 V
	Ignition switch ON H4 position	Below 1.5 V
	Ignition switch ON L4 position	10 to 14 V
F15-3 (LO) - Body ground	Ignition switch ON 2WD position	10 to 14 V
	Ignition switch ON H4 position	Below 1.5 V
	Ignition switch ON L4 position	Below 1.5 V

Text in Illustration

*a	Component with harness connected (Transfer Position Switch)

CHECK METER / GAUGE SYSTEM

REPLACE TRANSFER POSITION SWITCH

6.	CHECK 4WD INDICATOR LIGHT (GREEN)

(a) Turn the ignition switch to ON.

(b) for Automatic Transmission:

Move the shift lever to N.

for Manual Transmission:

Depress the clutch pedal.

(d) Wait for 60 seconds.

(e) Check the 4WD indicator light (green).

Result

Result	Proceed to
The 4WD indicator light (green) blinks*1 or turns off	A
The 4WD indicator light (green) rapidly blinks*2 or remains on	B

*1 (Blinking): Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)
*2 (Rapidly blinking): Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)

END

GO TO DTC P279E

7.	CHECK 4LO INDICATOR LIGHT

HINT:

Perform the following procedures with the vehicle stopped.

(a) Turn the ignition switch to ON.

(b) for Automatic Transmission:

Move the shift lever to N.

for Manual Transmission:

Depress the clutch pedal.

(d) Wait for 60 seconds.

(e) Check the 4LO indicator light.

Result

Result	Proceed to
The 4LO indicator light blinks*1 or turns off	A
The 4LO indicator light rapidly blinks*2 or remains on	B

*1 (Blinking): Blinks at 0.5 second intervals (0.5 seconds on and 0.5 seconds off)
*2 (Rapidly blinking): Blinks at 0.25 second intervals (0.25 seconds on and 0.25 seconds off)

END

8.	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

Result	Proceed to
DTC P279E is not output	A
DTC P279E is output	B

REPAIR CIRCUIT INDICATED BY OUTPUT CODE

9.	CHECK TRANSFER POSITION SWITCH

(a) Remove the transfer position switch with its connector still connected.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
F15-2 (2-4) - Body ground	Ignition switch ON 2WD position	Below 1.5 V
	Ignition switch ON H4 position	Below 1.5 V
	Ignition switch ON L4 position	10 to 14 V
F15-3 (LO) - Body ground	Ignition switch ON 2WD position	10 to 14 V
	Ignition switch ON H4 position	Below 1.5 V
	Ignition switch ON L4 position	Below 1.5 V

Text in Illustration

*a	Component with harness connected (Transfer Position Switch)

CHECK CAN COMMUNICATION SYSTEM

REPLACE TRANSFER POSITION SWITCH

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