Turn Signal Switch: Description and Operation

Steering Column Turn Signal and High Beam Stalk




Driver request signals from the steering column stalk are received by the LM as K-CAN-S messages. In the event of a bus fault, the signals are interpreted as analog values over a separate input line. The following functions are evaluated as CAN messages:

1) Single-touch flashing, left or right
2) Continuous flashing, left or right
3) High beam on
4) High beam off or headlight flasher

The command for cancelling of the turn signals comes from the steering angle sensor of the SZL.







Fault Detection

If no K-CAN messages are received from the steering-column stalk for a period exceeding 20s,the stalk is determined to be faulty. K-CAN communication continues to be attempted, although the light functions are then determined by the analog data line input. The fault status is terminated by newly detected K-CAN communication.

The following functions are determined as analog values over the data line in the event of a fault:

1) High mode on/off or headlight flasher
2) One-touch flashing, left/right
3) Neutral position