GF82.10-P-3008FL Turn Signal Light Actuation, Function

GF82.10-P-3008FL Turn Signal Light Actuation, Function
MODEL 212.0/ 2

Function requirements, general
^ No overvoltage or undervoltage (operating voltage range U greater than or equal to 7 less than or equal to 17.5 V)

Turn signal light actuation, general
The turn signal light actuation consists of all functions for output of the turn signal, various warnings and feedback.
The master control unit for all turn signal functions is the front SAM control unit with fuse and relay module (N10/1).
The front SAM control unit prioritizes all flashing functions and sends a flasher frequency which contains the duration of the bright phase for the turn signal lamps, to the corresponding control units over the interior CAN (CAN B).
The turn signal light actuation encompasses the following partial functions:
^ Function sequence for turn indicators
^ Function sequence for hazard warning flashing

Additional function requirements for turn signaling
^ Circuit 15R ON
The electronic ignition lock control unit (N73) sends the status of circuit 15 to the front SAM control unit over the interior CAN.

Function sequence for turn indicators
The turn signaling function encompasses the following subfunctions:
^ Function sequence for left turn signal indicator
^ Function sequence for right turn signal indicator
^ Function sequence for touch turn signal indicator

Function sequence for left turn signal indicator
The left turn signal function is requested by pushing the combination switch (S4) downward.
The steering column tube module control unit (N80) directly reads in the position of the combination switch and transmits it to the front SAM control unit via the chassis CAN (CAN E).
The front SAM control unit receives the switch position of the combination switch, forwards the "Left turn signaling" (flasher frequency) request over the interior CAN to the corresponding control units and actuates the left front turn signal light (E1e5) in the left front lamp unit (E1).
The left front door control unit (N69/1) receives the flasher frequency and actuates the left outside mirror turn signal lamp (E6/5).
The rear SAM control unit with fuse and relay module (N10/2) receives the flasher frequency and actuates the left rear turn signal light (E3e1) in the left rear lamp unit (E3).
In vehicles with code (550) Trailer hitch, the trailer recognition control unit (N28/1) receives the flasher frequency and actuates the left turn signal light on the trailer via the trailer socket (X58).

Function sequence for right turn signal indicator
The right turn signal function is requested by pushing the combination switch upward.
The steering column tube module control unit reads in the position of the combination switch directly and transmits it to the front SAM control unit via the chassis CAN.
The front SAM control unit sends the "Right turn signaling" (flasher frequency) request to the corresponding control units over the interior CAN and actuates the right front turn signal light (E2e5) in the right front lamp unit (E2).
The right front door control unit (N69/2) receives the flasher frequency and actuates the right outside mirror turn signal lamp (E6/6).
The rear SAM control unit receives the flasher frequency and actuates the right rear turn signal light (E4e1) in the right rear lamp unit (E4).
The trailer recognition control unit receives the flasher frequency and actuates the right turn signal light on the trailer via the trailer socket.

Function sequence for touch turn signaling
With regard to signal flow, the function sequence of the touch turn signal function corresponds to that of the left turn signal and right turn signal functions. The difference is in the triggering and ending of the turn signal procedure.
To trigger the touch turn signaling function, the combination switch must only be pressed briefly (t < 440 ms) in the desired turn signal direction.
Three flashing cycles are then output by the front SAM control unit.
The touch turn signaling function is interrupted by means of actuation of the hazard warning flasher function or activation of the combination switch in the opposite direction
Each active function is displayed for the driver by actuating the left turn signal light indicator lamp (A1e1) or the right turn signal light indicator lamp (A1e2) and the acoustic turn signal light function check (A1h2).
For this purpose, the instrument cluster (A1) receives the flasher frequency transmitted by the front SAM control unit via interior CAN.
If a turn signal light or turn signal lamp fails, the frequencies of the turn signal indicator lamps and the turn signal light function check in the instrument cluster double to f = 3 Hz
The flashing frequency of the turn signal lights and the turn signal lamps of f = 1.5 Hz remains the same.
Substitute lamp actuation:
If the left rear turn signal light fails, the brake light and the outer left taillight (E3e11) are actuated instead, and if the right rear turn signal light fails, the brake light and outer right taillight (E4e11) are actuated in its place.

Function sequence for hazard warning flashing
The function sequence for the hazard warning flasher is identical to that for turn signaling in terms of signal flow.
However, all the turn signal lights and turn signal lamps on the vehicle are actuated synchronously.
In addition to the indicator lamps in the instrument cluster, the indicator lamp in the hazard warning flasher switch (S6/1s1) in the instrument panel switch group (S6/1) is also actuated by the front SAM control unit over the instrument panel LIN (LIN 1).
Depending on the status of circuit 15, two duty cycles are output by the front SAM control unit:
- With circuit 15R On: light 58 %, dark 42 %
- With circuit 15R Off: light 35 %, dark 65 %
The hazard warning flashing function encompasses the following subfunctions:
^ Function sequence for hazard warning flashing, manual
^ Function sequence, hazard warning flashing after emergency braking
^ Function sequence for hazard warning flashing for airbag deployment
^ Function sequence for hazard warning flashing in the event of crash detection
^ Function sequence, feedback from locking/unlocking of central locking (CL)
^ Function sequence for antitheft alarm system (ATA) flashing (with code (551) Antitheft alarm system (ATA))

Function sequence, hazard warning flashing, manual
The manual hazard warning flashing function is activated by pressing the hazard warning flasher switch.
The front SAM control unit reads in the status of the hazard warning flasher switch via instrument panel LIN.
Afterwards all the turn signal lights and turn signal lamps on the vehicle are actuated synchronously.

Additional function requirements, hazard warning flashing after emergency braking
^ Circuit 15 On (transmitted by the electronic ignition lock control unit via the interior CAN)
^ Emergency braking detected within t = 500 ms (vehicle speed v > 70 km/h and Brake Assist System active or vehicle deceleration a > 7.5 m/s 2)

Function sequence, hazard warning flashing after emergency braking
In the event of emergency braking, the Electronic Stability Program control unit (N30/4) (without code (233) DISTRONIC PLUS except model 212.074/077/274/277) or the Premium Electronic Stability Program control unit (N30/7) (with code (233) DISTRONIC PLUS or model 212.074/077/274/277) sends a corresponding signal over the chassis CAN to the front SAM control unit.
If the vehicle is decelerated below the speed threshold of v = 3 km/h due to the emergency braking, the front SAM control unit activates the hazard warning flasher function by means of issuing the flasher frequency via interior CAN.
All turn signal lights and the turn signal lamps on the vehicle are actuated synchronously.
The instrument cluster sends the vehicle speed to the front SAM control unit over the interior CAN.
This function is deactivated by pressing the hazard warning flasher switch or upon exceeding a speed of v = 10 km/h.

Additional function requirements for hazard warning flashing for airbag deployment
^ Deceleration a > 4 g

Function sequence for hazard warning flashing for airbag deployment
If an airbag is deployed, the supplemental restraint system control unit (N2/10) transmits an appropriate signal to the front SAM control unit via the chassis CAN. The front SAM control unit then actuates the hazard warning flashing function by means of outputting the flasher frequency over the interior CAN.
All turn signal lights and the turn signal lamps on the vehicle are actuated synchronously.
This function is deactivated by pressing the hazard warning flasher switch or by globally unlocking the central locking.

Additional function requirements for hazard warning flashing for crash recognition
^ Deceleration a > 6 g

Function sequence for hazard warning flashing in the event of crash detection
A crash sensor is integrated into the front SAM control unit.
If this detects a crash event during a time-out of the supplemental restraint system control unit, the front SAM control unit initiates the hazard warning flashing function by issuing the flasher frequency over the interior CAN.
This serves to avoid any inadvertent activation of the local crash sensor.
All turn signal lights and the turn signal lamps on the vehicle are actuated synchronously.
This function is deactivated by pressing the hazard warning flasher switch or by globally unlocking the central locking.

Function sequence, feedback from locking/unlocking of central locking (CL)
When the central locking system is locked/unlocked, the electronic ignition lock control unit requests the hazard warning flashing function via the interior CAN. To this end, the electronic ignition lock control unit sends the status of the central locking over interior CAN to the front SAM control unit.
The front SAM control unit activates the hazard warning flashing function for one flasher cycle when the central locking system is unlocked, and for three flasher cycles when the central locking system is locked.
All turn signal lights and the turn signal lamps on the vehicle are actuated synchronously.
All vehicle doors must be closed in order to output the hazard warning flashing function.
The trunk lid (model 212.0) or the liftgate (model 212.2) is considered a vehicle door.

Function sequence for ATA flashing (with code (551) Antitheft alarm system (ATA) [EDW])
If an ATA [EDW] alarm is triggered, the rear SAM control unit requests the hazard warning flasher function over the interior CAN.
This request must be transmitted cyclically so that the flasher frequency results from the bright time and the cycle time.
The front SAM control unit receives this request, and then generates a corresponding flasher frequency which is sent over the interior CAN.
All turn signal lights and the turn signal lamps on the vehicle are actuated synchronously.