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Turn signal indicator actuation, function - GF82.10-P-3008GN

MODEL 166 as of model year 2016 

MODEL 292 

General function requirement 

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 flashing functions is the SAM control unit (N10). The SAM control unit prioritizes all flashing requests and sends a flasher frequency with the duration of the bright phase of the turn signal lamps via interior CAN (CAN B).

IMPORTANT The respective active function is visually displayed to the driver via the left turn signal light indicator lamp (A1e1) or the right indicator light indicator lamp (A1e2). The acoustic feedback is output through the instrument cluster speaker (H4/61). The instrument cluster (A1) receives the flasher frequency sent by the SAM control unit over the interior CAN for this. If a turn signal light or turn signal lamp fails, the frequencies of the turn signal indicator lamps and the instrument cluster speaker are doubled. The flashing frequency of the turn signal lights and turn signal lights of f = 1, 5 Hz continues to remain.

IMPORTANT Visual and audible feedback is only issued when the instrument cluster is active. Detailed information on activating the instrument cluster is available in the separate function description for the "Instrument cluster (IC) function".

IMPORTANT If turn signal light actuation has been activated, the daytime running lights (without CODE 498 (Japan version)) on the respective side are deactivated.

The turn signal light actuation encompasses the following partial functions:

Additional function requirements for turn signaling 

IMPORTANT The status of circuit 15 is sent by the electronic ignition lock control unit (N73) via the interior CAN to the SAM control unit.

Function sequence for turn indicators 

The turn signaling function encompasses the following subfunctions:

Function sequence, left turn signaling 

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 sends this via chassis CAN 1 (CAN E1), electronic ignition lock control unit and interior CAN to the SAM control unit.

The SAM control unit receives the position of the combination switch and sends the "Left turn signaling" request (flasher frequency) via interior CAN to the following control units:

On vehicles without CODE 640 (High-performance LED) and without CODE 641 (Dynamic left-hand traffic LED headlamp) and without CODE 642 (Dynamic right-hand traffic LED headlamp), the SAM control unit directly actuates the left front turn signal light (E1e5) in the left front lamp unit (E1).

The left headlamp control unit receives the flasher frequency and actuates the left front turn signal light directly.

The left front door control unit receives the flasher frequency and actuates the left outside mirror turn signal lamp (E6/5) directly.

The SAM control unit receives the flasher frequency and actuates the following components:

Left rear lamp unit (E3):

On vehicles with CODE 550 (Trailer hitch), the trailer recognition control unit receives the flasher frequency and actuates the left turn signal light on the trailer via the trailer socket (X58).

IMPORTANT The left turn signal can be overridden by the hazard warning flasher function, and vice versa.

Function sequence, right turn signaling 

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 forwards it via chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit.

The SAM control unit receives the position of the combination switch and sends the "Right turn signaling" request (flasher frequency) via interior CAN to the following control units:

On vehicles without CODE 640 (High-performance LED) and without CODE 641 (Dynamic left-hand traffic LED headlamp) and without CODE 642 (Dynamic right-hand traffic LED headlamp), the SAM control unit directly actuates the right front turn signal light (E2e5) in the right front lamp unit (E2).

The left headlamp control unit receives the flasher frequency and actuates the right front turn signal light directly.

The right front door control unit receives the flasher frequency and actuates the right outside mirror turn signal lamp (E6/6) directly.

The SAM control unit receives the flasher frequency and actuates the following components:

Right rear lamp unit (E4):

In vehicles with CODE 550 (Trailer hitch), the trailer recognition control unit receives the flasher frequency and actuates the right turn signal light on the trailer over the trailer socket.

IMPORTANT The right turn signal can be overridden by the hazard warning flasher function, and vice versa.

Function sequence, one-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. As a result, three flashing cycles are output by the SAM control unit. The one-touch turn signaling function is overridden when the hazard warning flasher function is actuated or the combination switch is activated in the opposite direction.

Function sequence, hazard warning flashing 

The hazard warning flasher function sequence is the same as that for turn signaling with regard to the 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 hazard warning system button (N72/1s5) in the upper control panel control unit (N72/1) is actuated by the SAM control unit via the battery sensor LIN (LIN B15).

Depending on the status of circuit 15, two duty cycles are output by the SAM control unit:

IMPORTANT If the malfunction of a turn signal light or a turn signal lamp is detected during hazard warning flashing, the frequencies of the turn signal light indicator lamps and the instrument cluster speaker are not doubled.

The hazard warning flashing function encompasses the following subfunctions:

Function sequence for hazard warning flashing, manual 

The manual hazard warning flasher function is activated by pressing the hazard warning system button. The SAM control unit reads in the status of the hazard warning system button over the battery sensor LIN. Following this, all turn signal lights and turn signal lights on the vehicle are actuated synchronously.

Additional function requirements for hazard warning flasher during emergency braking 

Function sequence for hazard warning flasher after emergency braking 

In the event of emergency braking, the Electronic Stability Program control unit (N30/4) sends a corresponding signal to the SAM control unit over the chassis CAN 1, electronic ignition lock control unit and the interior CAN.

If the vehicle is decelerated below the speed of v = 3 km/h due to emergency braking, the SAM control unit activates the hazard warning flasher function by issuing the flasher frequency over the interior CAN.

All turn signal lights and turn signal lamps are actuated at the same time on the vehicle.

The instrument cluster sends the vehicle speed to the SAM control unit over the interior CAN.

The hazard warning flasher is deactivated by pressing the hazard warning system button or upon exceeding a speed of v = 10 km/h.

Additional function requirements for hazard warning flasher when airbag deployed 

Function sequence for hazard warning flasher when airbag deployed 

When an airbag is deployed, the supplemental restraint system control unit (N2/10) sends a corresponding signal via chassis CAN 1 and also over a direct line to the SAM control unit.

The SAM control unit then initiates the hazard warning flashing function by means of outputting the flasher frequency via interior CAN.

All turn signal lights and turn signal lamps are actuated at the same time on the vehicle.

This function is deactivated by pressing the hazard warning system button 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. To this end, the electronic ignition lock control unit sends the status of the central locking over interior CAN to the SAM control unit.

The 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.

IMPORTANT The detailed description of this function can be found in the separate "Central locking (CL [ZV]), function" description.

Function sequence for anti-theft alarm system (ATA [EDW]) - Flashing (with CODE 551 (Anti-theft alarm system (ATA [EDW])) 

When an ATA [EDW] alarm is triggered, the SAM control unit initiates the hazard warning flashing function by issuing the flasher frequency over the interior CAN.

Following this, all turn signal lights and turn signal lights on the vehicle are actuated synchronously.

IMPORTANT The detailed description of this function can be found in the separate description "Anti-theft alarm system (ATA [EDW]), function".

Function sequence for PRE-SAFE rear end turn signaling (with CODE 253 (Rear-end collision warning and protective system)) 

If a vehicle is detected in the area to the rear of the vehicle, and it is deemed to be in an accident-critical position, then the driver of the vehicle in the rear is warned through actuation of the vehicle's rear turn signal lights (without CODE 460 (Canada version) and without CODE 494 (USA version)).

IMPORTANT The detailed description of this function can be found in the separate description "Rear-end PRE-SAFE function".

Electrical function schematic, turn signal light actuation PE82.10-P-2055-97NBA
Overview of exterior lights system components GF82.10-P-9998GN 
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