Inspection Procedure

HINT:

• When U0073/94, U0123/62, U0124/95 or U0126/63 is output together with C1231/31 inspect and repair the trouble areas indicated by U0073/94, U0123/62, U0124/95 or U0126/63 first.
• When the speed sensor or the yaw rate sensor has trouble, DTCs for the steering angle sensor may be output even when the steering angle sensor is normal. When DTCs for the speed sensor or yaw rate sensor are output together with other DTCs for the steering angle sensor, inspect and repair the speed sensor and yaw rate sensor first, and then inspect and repair the steering angle sensor.
• Start the inspection from "CHECK HARNESS AND CONNECTOR" when using the intelligent tester and from "CHECK DTC" when not using the intelligent tester.

1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION) 
   1. Using the intelligent tester, check for any momentary interruption in the wire harness and connectors between the skid control ECU and the steering angle sensor (see CHECK FOR INTERMITTENT PROBLEMS ).

   DATA LIST: ABS/VSC 

   NORMAL CONDITION CHART
   
   

   Item (Display)	Measurement Item / Range (Display)	Normal Condition
   STEERING OPN	Steering sensor open detection / ERROR or NORMAL	ERROR: Momentary interruption NORMAL: Normal

   OK: 

   There are no momentary interruptions. 

   HINT:

   Perform the above inspection before removing the sensor and connector.

   NG:  Go to step  4

   OK: Go to next step 

2. CHECK DTC 
   1. Clear the DTC (see DTC CHECK / CLEAR ).
   2. Turn the engine switch off.
   3. Turn the engine switch on (IG) again and check that no CAN communication system DTC is output.
   4. Drive the vehicle and turn the steering wheel to the right and left at a speed of 24 mph (35 km/h) and check that no speed sensor and yaw rate sensor DTCs are output.

   Result 

   RESULT CHART
   
   

   Display (DTC Output)	Proceed To
   No CAN communication system DTC and the speed sensor or yaw rate sensor DTC are output.	A
   CAN communication system DTC is output.	B (see DIAGNOSIS SYSTEM )
   Speed sensor or yaw rate sensor DTC is output.	B (see DIAGNOSTIC TROUBLE CODE CHART )

   HINT:

   • If there is a malfunction in the speed sensor or the yaw rate sensor, an abnormal value may be output although the steering angle sensor is normal.
   • If the speed sensor and the yaw rate sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.

   B: REPAIR CIRCUIT INDICATED BY OUTPUT CODE 

   A: Go to next step 

3. INSPECT STEERING ANGLE SENSOR (IG, BAT AND ESS TERMINAL) 
   1. Remove the steering wheel and the column cover lower.
   2. Disconnect the steering angle sensor connector.
   3. Measure the voltage according to the value(s) in the table below.

      Voltage 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
      
      

      Tester Connection	Condition	Specified Condition
      K19-1 (IG) - Body ground	Engine switch on (IG)	10 to 14 V
      K19-3 (BAT) - Body ground	Always	10 to 14 V

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

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION REFERENCE CHART
      
      

      Tester Connection	Condition	Specified Condition
      K19-2 (ESS) - Body ground	Engine switch off	Below 1 Ω

      HINT:

      If troubleshooting has been carried out according to the problem symptoms table, refer back to the table and proceed to the next step (see PROBLEM SYMPTOMS TABLE ).

   Fig 1: Identifying Steering Angle Sensor Connector Terminals

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

   NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (IG, BAT OR ESS CIRCUIT) 

   OK: REPLACE STEERING ANGLE SENSOR 

4. CHECK AND REPLACE HARNESS AND CONNECTOR (STEERING ANGLE SENSOR TO SKID CONTROL ECU) 
5. RECONFIRM DTC 
   1. Clear the DTC (see DTC CHECK / CLEAR ).
   2. Start the engine.
   3. Drive the vehicle and turn the steering wheel to the right and left at a speed of 24 mph (35 km/h) or more.
   4. Check that the same DTC is recorded (see DTC CHECK / CLEAR ).

   Result 

   RESULT CHART
   
   

   Display (DTC Output)	Proceed To
   DTC (C1231/31) is not output	A
   DTC (C1231/31) is output	B

   HINT:

   If troubleshooting has been carried out according to the problem symptoms table, refer back to the table and proceed to the next step (see PROBLEM SYMPTOMS TABLE ).

   B:  Go to step  2

   A: END