DTC B1312[15] Steering Switch Input Circuit Short to Battery or Open (BCM)

1. DTC B1312[15] description

The cruise control switch signal is input to the BCM. Because the resistances are different between each switch of the cruise control switch, the BCM determines which switch is pressed based on the resistance. The BCM sends the cruise control switch signal to the stereo camera via the CAN communication circuit. If the BCM detects a malfunction in the cruise control switch input circuit, the DTC is set.

The cruise control switch input to the BCM consists of the following switches.

  • Inter-vehicular distance switch
  • SET/+ switch
  • LKAS switch
  • Main switch
  • CANCEL switch
  • RES switch
  • SET/- switch

2. Condition for setting DTC B1312[15]

  • The BCM detects an open circuit or a short to the power supply in the cruise control switch input circuit for 2 seconds or more.

3. Action taken when DTC B1312[15] sets

  • The cruise control switch does not operate normally.
  • Current and past failures are set.
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