Part | Description
BCM |

- Detects each switch condition by the combination switch reading function.
- Judges the outside brightness from the optical sensor signal.
- Judges the OFF timing according to the vehicle condition.
- Judges the ON/OFF status of the exterior lamp and each illumination according to the outside brightness and the vehicle condition.
  Requests ON/OFF of each relay to IPDM E/R (with CAN communication).

IPDM E/R | Controls the integrated relay, and supplies voltage to the load according to the request from BCM (with CAN communication).
Combination switch (Lighting & turn signal switch) | Refer to System Diagram.
Optical sensor | Refer to Description.