ELECTRONICALLY CONTROLLED BRAKE SYSTEM, Diagnostic DTC:C1231

DESCRIPTION

The skid control ECU assembly inputs steering sensor signals via the CAN communication. When a malfunction occurs in the communication line with the steering sensor, DTC U0126 (Lost Communication with Steering Angle Sensor Module) is output.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

PROCEDURE

1. CHECK DTC

   
   

   1. Clear the DTCs Click here.

   2. Turn the power switch off.

   3. Turn the power switch on (IG) again and check that no CAN communication system DTC is output (for LHD: See page , for RHD: Click here.

   4. Drive the vehicle at a speed of 35 km/h (22 mph) and turn the steering wheel to the right and left and check that no speed sensor and/or yaw rate sensor DTCs are output Click here.

      Result
      Result Proceed to No CAN communication system, speed sensor, yaw rate sensor DTCs are output A CAN communication system DTC is output (for LHD) B CAN communication system DTC is output (for RHD) C Speed sensor and/or yaw rate sensor DTC is output D

      Tech Tips

      
      

      • If there is a malfunction in the speed sensor or the yaw rate sensor, an abnormal value may be output although the steering sensor is normal.

      • If speed sensor and yaw rate sensor DTCs are output simultaneously, repair these 2 sensors and inspect the steering sensor.

   
   

   B

   INSPECT CAN COMMUNICATION SYSTEM Click here

   C

   INSPECT CAN COMMUNICATION SYSTEM Click here

   D

   REPAIR CIRCUITS INDICATED BY OUTPUT DTCS Click here

   A

2. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

   
   

   1. Turn the power switch off.

   2. Remove the steering wheel and the column cover.

   3. 

      Text in Illustration

      *A	w/o Dynamic Rear Steering System
      *B	w/ Dynamic Rear Steering System
      *a	Front view of wire harness connector (to Steering Sensor)

      Make sure that there is no looseness at the locking part and the connecting part of the connector.

   4. Disconnect the steering sensor connector.

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

      Standard Voltage
      w/o Dynamic Rear Steering System Tester Connection Switch Condition Specified Condition N34-4 (IG1) - Body ground Power switch on (IG) 11 to 14 V
      w/ Dynamic Rear Steering System Tester Connection Switch Condition Specified Condition N33-4 (IG1) - Body ground Power switch on (IG) 11 to 14 V

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

      Standard Resistance
      w/o Dynamic Rear Steering System Tester Connection Condition Specified Condition N34-1 (ESS) - Body ground Always Below 1 Ω
      w/ Dynamic Rear Steering System Tester Connection Condition Specified Condition N33-1 (ESS) - Body ground Always Below 1 Ω

      Result

      Result	Proceed to
      NG	A
      OK (w/o Dynamic Rear Steering System)	B
      OK (w/ Dynamic Rear Steering System)	C

   
   

   A

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   C

   CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL) Click here

   B

3. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

   
   
   1. 

      Text in Illustration

      *a	Front view of wire harness connector (to Steering Sensor)

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

      Standard Voltage
      Tester Connection Condition Specified Condition N34-8 (BAT) - Body ground Always 11 to 14 V

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.

   
   

   OK

   REPLACE STEERING SENSOR Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)

4. CHECK HARNESS AND CONNECTOR (POWER SOURCE TERMINAL)

   
   
   1. 

      Text in Illustration

      *a	Front view of wire harness connector (to Steering Sensor)

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

      Standard Voltage
      Tester Connection Condition Specified Condition N33-5 (BAT) - Body ground Always 11 to 14 V

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.

   
   

   OK

   REPLACE STEERING SENSOR Click here

   NG

5. CHECK HARNESS AND CONNECTOR (FRONT STEERING CONTROL ECU - STEERING SENSOR)

   
   

   1. Disconnect the N104 front steering control ECU connector.

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

      Standard Resistance
      Tester Connection Condition Specified Condition N104-1 (+BO) - N33-5 (BAT) Always Below 1 Ω N104-1 (+BO) - Body ground Always 10 kΩ or higher

   
   

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR

   OK

6. CHECK HARNESS AND CONNECTOR

   

   Text in Illustration

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

   
   

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

      Standard Voltage
      Tester Connection Condition Specified Condition N104-7 (+BI) - Body ground Always 11 to 14 V

      Tech Tips

      If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step Click here.

   
   

   OK

   REPLACE FRONT STEERING CONTROL ECU Click here

   NG

   REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT)