2009 Toyota Matrix Base, AutomaticFACTORY OEM SERVICE PROCEDURE

DTC C1231/31 Steering Angle Sensor Circuit Malfunction: Description

Steering angle sensor signals are sent to the skid control ECU via the CAN communication system. When there is a malfunction in the CAN communication system, it will be detected by the steering angle sensor zero point malfunction diagnostic function.

DTC DETECTION CONDITION AND TROUBLE AREA REFERENCE CHART

DTC Code DTC Detection Condition Trouble Area
C1231/31 When ECU IG1 terminal voltage is between 9.5 and 17.4 V, a steering angle sensor malfunction signal is received.
  • Steering angle sensor
  • Steering angle sensor circuit
  • Steering angle sensor power supply
  • Brake actuator assembly (Skid control ECU)
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