Toyota Tacoma (2015-2018) Service Manual: Transfer L4 Position Switch Circuit (C1268)

Toyota Tacoma (2015-2018) Service Manual / Brake Control / Dynamic Control Systems / Vehicle Stability Control System(for Hydraulic Brake Booster) / Transfer L4 Position Switch Circuit (C1268)

DESCRIPTION

A-TRAC is activated if wheel skid is detected while the transfer is in the L4 position.

DTC Code	DTC Detecting Condition	Trouble Areas
C1268	L4 detection switch signal input to skid control ECU (master cylinder solenoid) does not match L4 detection switch signal output from ECM.	L4 detection switch (transfer shift actuator assembly) L4 detection switch (transfer shift actuator assembly) circuit Skid control ECU (master cylinder solenoid)

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

When replacing the skid control ECU (master cylinder solenoid), perform zero point calibration (See page HINT: ).

HINT:

When DTC U0114 is output together with DTC C1268, inspect and repair the trouble areas indicated by DTC U0114 first (See page PROCEDURE ).

PROCEDURE

1.	INSPECT TOUCH SELECT 2-4 AND HIGH-LOW SYSTEM

(a) Turn the 4WD control switch (transfer position switch) to L4, and then drive the vehicle and check that there are no problems with the touch select 2-4 and high-low system.

OK:

There are no problems with the touch select 2-4 and high-low system.

GO TO TOUCH SELECT 2-4 AND HIGH-LOW SYSTEM

2.	CHECK HARNESS AND CONNECTOR (EXI TERMINAL)

(a) Connect the S1 skid control ECU (master cylinder solenoid) connector.

(b) Turn the 4WD control switch (transfer position switch) to L4.

(d) Disconnect the S1 skid control ECU (master cylinder solenoid) connector.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
S1-27 (EXI) - Body ground	Ignition switch ON 4WD control switch (transfer position switch) set to L4	Below 1.5 V

Text in Illustration

*a	Front view of wire harness connector (to Skid Control ECU (Master Cylinder Solenoid))

(f) Reconnect the S1 skid control ECU (master cylinder solenoid) connector.

(g) Reconnect the E13 ECM connector.

(h) Turn the 4WD control switch (transfer position switch) to 2WD or H4.

(i) Disconnect the E13 ECM connector.

(j) Disconnect the S1 skid control ECU (master cylinder solenoid) connector.

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

Standard Voltage:

Tester Connection	Switch Condition	Specified Condition
S1-27 (EXI) - Body ground	Ignition switch ON 4WD control switch (transfer position switch) set to 2WD or H4	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR (EXI TERMINAL)

3.	RECONFIRM DTC OUTPUT

(a) Turn the ignition switch off.

(b) Reconnect the S1 skid control ECU (master cylinder solenoid) connector.

(d) Turn the ignition switch to ON.

(e) Clear the DTC (See page (f) Turn the ignition switch off. ).

(f) Turn the ignition switch off.

(g) Start the engine.

(h) Turn the 4WD control switch (transfer position switch) to 2WD or H4.

(i) Turn the 4WD control switch (transfer position switch) to L4, drive the vehicle, and then check for DTCs.

Result

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

REPLACE MASTER CYLINDER SOLENOID

USE SIMULATION METHOD TO CHECK

Power Supply Drive Circuit (C1257)

DESCRIPTION The motor relay (semiconductor relay) is built into the hydraulic brake booster and drives the pump motor based on a signal from the skid control ECU (master cylinder solenoid). ...

Low Output Signal of Front Speed Sensor RH (Test Mode DTC) (C1271,C1272,C1401,C1402)

DESCRIPTION The speed sensor detects the wheel speed and sends the appropriate signals to the skid control ECU (master cylinder solenoid). These signals are used for brake control. The speed sen ...

Other materials:

Lost Communication with ECM (C1437)
DESCRIPTION The skid control ECU (brake actuator assembly) receives signals from the ECM via the CAN communication system. DTC No. Detection Item DTC Detection Condition Trouble Area C1437 Lost Communication with ECM ...

Communication Error from VSC to ECM Invalid Serial Data Received (P163081)
DESCRIPTION The skid control ECU (master cylinder solenoid)*1 or skid control ECU (brake actuator assembly)*2 sends signals such as cruise control cancel signals and brake demand response signals to the ECM when the dynamic radar cruise control system is operating. DTC No. ...

Operation Check
OPERATION CHECK 1. CHECK WINDOW LOCK SWITCH HINT: Before performing the window lock switch operation check, make sure that the window lock switch is off (the switch is not pushed in). (a) Check that the front passenger and rear windows cannot be operated from each power window regulator swit ...