DTC C1258: Open Circuit in Transfer 4WD Position Switch Circuit; DTC C1340: Center Differential Lock Circuit [08/2015 - 08/2019]: Procedure

1. Disconnect the A6 skid control ECU connector.
2. Measure the voltage according to the value(s) in the table below.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   Standard Voltage

   Tester Connection	Switch Condition	Specified Condition
   A6-27 (EXI) - Body ground	Ignition switch ON	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

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

   RESULT
   
   

   Result	Proceed to
   OK	A
   NG (for Part-time 4WD)	B
   NG (for Full-time 4WD)	C

Result: 

B 

See step  3

Result: 

C 

See step  4

Result: 

A 

See step  2

1. Clear the DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
2. Check for DTCs (Refer to DTC CHECK / CLEAR [08/2015 - 08/2019] ).
   RESULT
   
   

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

Result: 

A 

REPLACE MASTER CYLINDER SOLENOID 

(Refer to DISASSEMBLY [08/2015 - ] )

Result: 

B 

USE SIMULATION METHOD TO CHECK 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [08/2015 - 08/2019] )

1. Disconnect the A6 skid control ECU connector.
2. Disconnect the F47 four wheel drive control ECU connector.
3. Disconnect the D1 A.D.D. actuator connector.
4. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   W/ REAR DIFFERENTIAL LOCK
   
   

   Tester Connection	Condition	Specified Condition
   A6-27 (EXI) - F47-15 (ADD)	Always	Below 1 Ω
   A6-27 (EXI) - D1-3 (ADD)	Always	Below 1 Ω
   A6-27 (EXI) - Body ground	Always	10 kΩ or higher
   D1-4 (GND) - Body ground	Always	Below 1 Ω

   W/O REAR DIFFERENTIAL LOCK
   
   

   Tester Connection	Condition	Specified Condition
   A6-27 (EXI) - F47-14 (ADD)	Always	Below 1 Ω
   A6-27 (EXI) - D1-3 (ADD)	Always	Below 1 Ω
   A6-27 (EXI) - Body ground	Always	10 kΩ or higher
   D1-4 (GND) - Body ground	Always	Below 1 Ω

Result: 

OK 

GO TO TRANSFER SYSTEM (PROBLEM SYMPTOMS TABLE) 

(Refer to PROBLEM SYMPTOMS TABLE [08/2015 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR 

1. Disconnect the A6 skid control ECU connector.
2. Disconnect the F47 four wheel drive control ECU connector.
3. Disconnect the B47 transfer shift actuator assembly connector.
4. Measure the resistance according to the value(s) in the table below.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   A6-27 (EXI) - F47-14 (P1)	Always	Below 1 Ω
   A6-27 (EXI) - B47-9 (CDL)	Always	Below 1 Ω
   A6-27 (EXI) - Body ground	Always	10 kΩ or higher
   B47-10 (GND) - Body ground	Always	Below 1 Ω

Result: 

OK 

GO TO TRANSFER SYSTEM (PROBLEM SYMPTOMS TABLE) 

(Refer to PROBLEM SYMPTOMS TABLE [08/2015 - 08/2019] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR