DTC C1231/31: Steering Angle Sensor Circuit Malfunction [10/2015 - ]: Procedure

1. Clear the DTCs (Refer to DTC CHECK / CLEAR [10/2014 - ] ).
2. Turn the power switch off.
3. Turn the power switch on (IG) again and check that no CAN communication system DTCs are output.

   w/ Central Gateway ECU: Refer to DIAGNOSIS SYSTEM [10/2015 - ]

   w/o Central Gateway ECU: Refer to DIAGNOSIS SYSTEM [10/2015 - ]

4. Drive the vehicle at a speed of 35 km/h (22 mph), turn the steering wheel to the right and left, and check that no speed sensor and/or yaw rate and acceleration sensor DTCs are output (Refer to DTC CHECK / CLEAR [10/2014 - ] ).

   Result

   Result	Proceed to
   DTC C1231/31 is output.	A
   CAN communication system DTCs are output.	B
   Speed sensor and/or yaw rate and acceleration sensor DTCs are output.	C
   DTC C1231/31 is not output.	D

   HINT: 

   • When CAN communication system DTCs are output, repair the CAN communication system before repairing each corresponding sensor.
   • If there is a malfunction in the speed sensor or yaw rate and acceleration sensor (airbag ECU assembly), an abnormal value may be output even though the steering angle sensor is normal.
   • If speed sensor and yaw rate and acceleration sensor DTCs are output simultaneously, repair the sensors and inspect the steering angle sensor.

Result: 

B 

INSPECT CAN COMMUNICATION SYSTEM 

w/ Central Gateway ECU: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ]

w/o Central Gateway ECU: Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ]

Result: 

C 

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS 

(Refer to DIAGNOSTIC TROUBLE CODE CHART [10/2015 - ] )

Result: 

D 

USE SIMULATION METHOD TO CHECK 

(Refer to HOW TO PROCEED WITH TROUBLESHOOTING [10/2015 - ] )

Result: 

A 

See step  2

1. Turn the power switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

2. Remove the steering wheel and column cover.
3. Make sure that there is no looseness at the locking part and the connecting part of the connector.
4. Disconnect the D21 steering angle sensor connector.
5. Measure the voltage according to the value(s) in the table below.

   Standard Voltage

   Tester Connection	Condition	Specified Condition
   D21-4 (IG) - Body ground	Power switch on (IG)	11 to 14 V
   D21-5 (BAT) - Body ground	Always	11 to 14 V

   TEXT IN ILLUSTRATION
   
   

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

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (POWER SOURCE CIRCUIT) 

Result: 

OK 

See step  3

1. Turn the power switch off.

   Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

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

   Before measuring the resistance of the steering angle sensor, turn the power switch off and leave the vehicle for 1 minute or more without operating the key, switches or opening or closing the doors.

   Standard Resistance

   Tester Connection	Condition	Specified Condition
   D21-1 (ESS) - Body ground	1 minute after power switch off	Below 1 Ω

   TEXT IN ILLUSTRATION
   
   

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

   HINT: 

   If troubleshooting has been carried out according to Problem Symptoms Table, refer back to the table and proceed to the next step (Refer to PROBLEM SYMPTOMS TABLE [10/2015 - ] ).

Result: 

OK 

REPLACE STEERING ANGLE SENSOR 

(Refer to REMOVAL [10/2014 - ] )

Result: 

NG 

REPAIR OR REPLACE HARNESS OR CONNECTOR (GROUND CIRCUIT)