Toyota Tacoma 2015-2018 Service Manual: Lock Switch Circuit

Toyota Tacoma 2015-2018 Service Manual / Differential / Differential System(w/ Rear Differential Lock) / Lock Switch Circuit

WIRING DIAGRAM

PROCEDURE

1.	CHECK REAR DIFFERENTIAL LOCK INDICATOR LIGHT

(a) Turn the ignition switch to ON.

(b) for 4WD:

Finish switching to L4.

(d) Press the differential lock switch.

(e) After 60 seconds, check the rear differential lock indicator light.

Result

Result	Proceed to
Rear differential lock indicator light blinks or illuminates	A
Rear differential lock indicator light remains off regardless of switch operation	B
Rear differential lock indicator light remains illuminated regardless of switch operation	C
Rear differential lock indicator light rapidly blinks	D

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

END

GO TO STEP 8

GO TO DTC P17CC

2.	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

3.	READ VALUE USING TECHSTREAM (REAR DIFFERENTIAL LOCK SWITCH CONTROL SW (R))

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the ignition switch to ON.

(e) Enter the following menus: Powertrain / Four Wheel Drive / Data List.

(f) According to the display on the Techstream, read the Data List.

Four Wheel Drive

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Rear Differential Lock Control SW (R)	Differential lock switch status (differential lock switch input signal of R terminal on ECU side)/ ON or OFF	ON: Switch pressed and held OFF: Switch not pressed	-

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Rear Differential Lock Control SW (R)

Differential lock switch status (differential lock switch input signal of R terminal on ECU side)/

ON or OFF

ON: Switch pressed and held

OFF: Switch not pressed

OK:

Display changes according to differential lock switch operation.

GO TO STEP 5

4.	INSPECT COMBINATION METER ASSEMBLY

(a) Turn the ignition switch off.

(b) Perform Active Test of the combination meter assembly using the Techstream.

OK:

The rear differential lock indicator light turns on or off in accordance with the Techstream.

REPLACE 4 WHEEL DRIVE CONTROL ECU

CHECK METER / GAUGE SYSTEM

5.	INSPECT DIFFERENTIAL LOCK SWITCH

(a) Disconnect the G13 differential lock switch connector.

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

Standard Resistance:

Tester Connection	Switch Condition	Specified Condition
6 - 3	Switch not pressed	10 kΩ or higher
6 - 3	Switch pressed	Below 1 Ω

Text in Illustration

*a	Component without harness connected (Differential Lock Switch)

REPLACE DIFFERENTIAL LOCK SWITCH

6.	INSPECT ROOF CONSOLE BOX ASSEMBLY

(a) Remove the roof console box assembly.

for Double Cab: (See page )
for Access Cab: (See page )

Text in Illustration

Component without harness connected

(Roof Console Box Assembly)

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

Standard Resistance:

Tester Connection	Condition	Specified Condition
R44-6 (B) - 6 (B)	Always	Below 1 Ω
R44-12 (GND) - 3 (E)	Always	Below 1 Ω

Result

Result	Proceed to
OK	A
NG (for Double Cab)	B
NG (for Access Cab)	C

REPLACE ROOF CONSOLE BOX ASSEMBLY

7.	CHECK HARNESS AND CONNECTOR (4 WHEEL DRIVE CONTROL ECU - ROOF CONSOLE BOX ASSEMBLY)

(a) Disconnect the F13 4 wheel drive control ECU connector.

(b) Disconnect the R44 roof console box assembly connector.

Standard Resistance:

Tester Connection	Condition	Specified Condition
F13-15 (R) - R44-6 (B)	Always	Below 1 Ω
R44-12 (GND) - Body ground	Always	Below 1 Ω

REPLACE 4 WHEEL DRIVE CONTROL ECU

REPAIR OR REPLACE HARNESS OR CONNECTOR

8.	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

9.	READ VALUE USING TECHSTREAM (REAR DIFFERENTIAL LOCK INDICATOR REQUEST)

(a) Turn the ignition switch off.

(b) Connect the Techstream to the DLC3.

(d) Turn the ignition switch to ON.

(e) Enter the following menus: Powertrain / Four Wheel Drive / Data List.

(f) According to the display on the Techstream, read the Data List.

Four Wheel Drive

Tester Display	Measurement Item/Range	Normal Condition	Diagnostic Note
Rear Differential Lock Indicator Request	Rear differential lock indicator light request/ Blink4*, Blink3, Blink2, Blink1, ON or OFF	Blink3: Indicator light rapidly blinks Blink2: Indicator light blinks 3 times Blink1: Indicator light blinks ON: Indicator light illuminates OFF: Indicator light turns off	Blinking: 0.5 second intervals (0.5 seconds on and 0.5 seconds off) Rapidly blinking: 0.25 second intervals (0.25 seconds on and 0.25 seconds off) *: Item not supported, therefore not displayed

Tester Display

Measurement Item/Range

Normal Condition

Diagnostic Note

Rear Differential Lock Indicator Request

Rear differential lock indicator light request/

Blink4*, Blink3, Blink2, Blink1, ON or OFF

Blink3: Indicator light rapidly blinks
Blink2: Indicator light blinks 3 times
Blink1: Indicator light blinks
ON: Indicator light illuminates
OFF: Indicator light turns off

Blinking: 0.5 second intervals (0.5 seconds on and 0.5 seconds off)
Rapidly blinking: 0.25 second intervals (0.25 seconds on and 0.25 seconds off)

*: Item not supported, therefore not displayed

(g) for 4WD:

Finish switching to L4.

(h) Turn the differential lock switch on and off several times and check the Techstream display condition of the rear differential lock indicator light.

Result

Result	Proceed to
Data List continues to display ON even when differential lock switch is operated	A
Data List display changes according to differential lock switch operation	B

REPLACE 4 WHEEL DRIVE CONTROL ECU

CHECK METER / GAUGE SYSTEM

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