GF82.10-P-3008RC Turn Signal Indicator Actuation, Function
GF82.10-P-3008RC Turn Signal Indicator Actuation, Function
Turn signal actuation in general
The turn signal light actuation comprises all functions for output of the turn signal indicator, various warnings and feedback. The rear SAM control unit with fuse and relay module (N10/2) is the master control unit for all turn signal functions. The rear SAM control unit prioritizes all incoming flashing functions and applies a flasher frequency with the time period of the turn signal lamp bright phase to the interior CAN.
The flashing frequency is f = 1.5 Hz with a bright/dark duty cycle of 52 % to 48 %.
Turn signal light actuation is comprised of the following subfunctions:
^ Operational sequence turn indicators
^ Function sequence, hazard warning flashing
^ Function sequence for visual feedback
Additional function requirements, turn signaling
^ C. 15R On
Operational sequence turn indicators
The turn signaling function is comprised of the following subfunctions:
^ Function sequence, left turn signal indicator
^ Function sequence, right turn signal indicator
^ Function sequence, touch turn signal indicator
Function sequence, left turn signal indicator
The terminal status of circuit 15 is sent by the EIS [EZS] control unit (N73) to the interior CAN. The applied position of the combination switch (S4) is read in by the steering column tube module (N80) and transmitted over the interior CAN to the rear SAM control unit.
The rear SAM control unit sends the request to output the left turn signal function as a flasher frequency to the corresponding control units on the interior CAN and actuates the left turn signal light (E3e1) in the left taillamp (E3).
The driver SAM control unit with fuse and relay module (N10/1) receives the flasher frequency and actuates the left turn signal light (E1e5) in the left front lamp unit (E1).
The left door control unit (N69/1) receives the flasher frequency and actuates the left outside mirror turn signal lamp (E6/5) an.
Function sequence, right turn signal indicator
The terminal status of circuit 15 is sent by the EIS [EZS] control unit to the interior CAN. The applied position of the combination switch is read in by the steering column tube module and transmitted over the interior CAN to the rear SAM control unit. The rear SAM control unit sends the request to output the right turn signal function as a flasher frequency to the corresponding control units on the interior CAN and actuates the right turn signal light (E4e1) in the right taillamp (E4).
The driver SAM control unit receives the flasher frequency and actuates the right turn signal light (E2e5) in the right front lamp unit (E2).
The right door control unit (N69/2) receives the flasher frequency and actuates the right outside mirror turn signal lamp (E6/6).
Function sequence, touch turn signal indicator
The function sequence for touch flashing matches that for the left and right flashing as far as the signal path is concerned. The difference lies in the triggering and ending of the turn signal procedure. The combination switch must only be operated briefly (t < 500 ms) in the desired turn signal direction. Three flashing cycles are output by the rear SAM control unit. Touch flashing is canceled by actuation of the hazard warning flasher function, by pressing the combination switch in the opposite direction or by a lock/unlock feedback request from the central locking system (CL [ZV]).
Function sequence, hazard warning flashing
The hazard warning flashing function is comprised of the following subfunctions:
^ Function sequence, hazard warning flashing
^ Function sequence, hazard warning flashing for danger braking
^ Function sequence, hazard warning flashing for airbag deployment
^ Function sequence, feedback from locking/unlocking of central locking (CL)
^ Function sequence, anti-theft alarm system (ATA [EDW]) flashing (with code (551) Antitheft alarm system (ATA [EDW]))
Function sequence, hazard warning flashing
The hazard warning flasher is activated by pressing the hazard warning system switch (N72/1s5). The status of the hazard warning system switch (N72/1) is read in by the upper control panel control unit and forwarded over the interior CAN to the rear SAM control unit. 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 lights on the vehicle are actuated synchronously.
Depending on the position of the transmitter key (A8/1) in the EIS [EZS] control unit, the rear SAM control unit issues two duty cycles:
- With circuit 15R On: bright 58 %, dark 42 %
- With circuit 15R Off: bright 35 %, dark 65 %
In addition to the displays in the instrument cluster, the indicator lamp in the hazard warning system switch is also actuated. To this end, the rear SAM control unit transmits a corresponding signal to the upper control panel control unit, which then actuates the indicator lamp in the hazard warning system switch.
Additional function requirements, hazard warning flashing for danger braking
^ Circuit 15 On
^ Manual hazard warning flashing inactive
^ Emergency braking within t = 500 ms recognized (vehicle speed v > 70 km/h and Brake Assist System active or vehicle deceleration a > 7.5 m/s2)
Function sequence, hazard warning flashing for danger braking
The vehicle speed and deceleration is determined by the ESP and BAS control unit (N47-5). In the event of an emergency braking maneuver the ESP and BAS control unit sends a corresponding signal to the engine compartment CAN. This signal is routed by the central gateway control unit (N93) to the interior CAN.
The rear SAM control unit receives it and initiates the hazard warning flashing function by the output of the flasher frequency on the interior CAN. All the turn signal lights and turn signal lamps on the vehicle are actuated synchronously for the period of min. t = 3 s.
The hazard warning flasher for danger braking is reset if one of the following conditions is met:
- Request of hazard warning flashing function by pressing the hazard warning system switch
- Brake released
- Speed v > 10 km/h
Additional function requirements, hazard warning flashing for airbag deployment
^ Deceleration a > 4 g
Function sequence, hazard warning flashing for airbag deployment
If an airbag is deployed, the restraint system control unit (N2/7) sends a corresponding signal over the interior CAN to the rear SAM control unit. The rear SAM control unit receives it and initiates the hazard warning flasher function by the output of the flasher frequency on the interior CAN.
This function is deactivated by operating the hazard warning system switch or by globally unlocking the central locking system.
Function sequence, feedback from locking/unlocking of central locking (CL)
When the central locking system is locked/unlocked, the hazard warning flashing function is requested by the EIS [EZS] control unit via the interior CAN.
When the central locking system is unlocked, the rear SAM control unit activates the hazard warning flashing function for one flasher cycle, when locking three flasher cycles are issued.
Function sequence ATA flashing
If an anti-theft alarm system alarm is triggered, the rear SAM control unit initiates the hazard warning flasher function by the output of the flasher frequency on the interior CAN. Following this, all turn signal lights and turn signal lamps on the vehicle are actuated synchronously.
Function sequence for visual feedback
The instrument cluster (A1) receives the flasher frequency sent over the interior CAN by the rear SAM control unit, and actuates the left turn signal indicator lamp (A1e1) or the right turn signal indicator lamp (A1e2) and the audible turn signal indicator (A1h2).
If the failure of a turn signal light or turn signal lamp is detected, the frequencies of the turn signal indicator lamp and audible turn signal indicator double in the instrument cluster.
The flashing frequency of the turn signal lights and turn signal lights of f = 1,5 Hz continues to remain.
