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(Turn Signal Indicator Actuation, Function - GF82.10-P-3008GR)

Model 166 

up to Model year 2016 

Function requirements, general 

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 transmits a flasher frequency with a time period of the bright phase of the turn signal lamps over the interior CAN (CAN B) to the corresponding control units.

A differentiation is made between the following versions of the left front lamp unit (E1) and the right front lamp unit (E2) in accordance with the vehicle equipment:

Halogen version lamp units:

The turn signal light functions are output through conventional light sources (bulbs).

The SAM control unit actuates the following components in the front lamp units for this:

Lamp units in xenon design:

Instead of conventional bulbs, light emitting diodes (LED) are used to output the turn signal light functions. For this, the left front actuation module, LED exterior lighting (E1n7) is located on the rear of the left front lamp unit and the right front actuation module, LED exterior lighting (E2n7) is located on the rear of the right front lamp unit.

To output the flashing functions, the SAM control unit switches a signal voltage (circuit 49a) through to the front actuation modules, LED exterior lighting.

The left front actuation module, LED exterior lighting actuates the following components in the left front lamp unit:

The right front actuation module, LED exterior lighting actuates the following components in the right front lamp unit:

IMPORTANT The front actuation modules, LED exterior lighting are diagnosed via the headlamp control unit (N71/1).

The turn signal light actuation encompasses the following partial functions:

Additional function requirements for turn signaling 

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

Function sequence for turn indicators 

The turn signaling function comprises the following subfunctions:

Function sequence, 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 switch 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 switch position of the combination switch, forwards the "left flasher" request as a flasher frequency to the corresponding control units over the interior CAN and actuates the following exterior light components:

The left front door control unit (N69/1) receives the flasher frequency and actuates the left outside mirror turn signal lamp (E6/5).

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 over the trailer socket (X58) (except CODE 460 (Canada version) and except CODE 494 (USA version)) or over the 7-pin trailer socket (X58/11) (with CODE 460 (Canada version) or CODE 494 (USA version)).

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 switch position of the combination switch directly and forwards it over the chassis CAN 1, electronic ignition lock control unit and interior CAN to the SAM control unit.

The SAM control unit receives the switch position of the combination switch, forwards the "left flasher" request as a flasher frequency to the corresponding control units over the interior CAN and actuates the following exterior light components:

The right front door control unit (N69/2) receives the flasher frequency and actuates the right outside mirror turn signal lamp (E6/6).

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.

Function sequence, touch turn signal indicator 

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 output by the SAM control unit. The one-touch turn signaling function is interrupted through actuation of the hazard warning flashing function or through actuation of the combination switch in the opposite direction.

IMPORTANT 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). 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 turn signal light function check in the instrument cluster double.

The flashing frequency of the turn signal lights and turn signal lights of f = 1, 5 Hz continues to remain.

IMPORTANT If the failure of a turn signal light or a turn signal lamp is detected during hazard warning flashing, the frequency of the turn signal light indicator lamps and the turn signal light function check does not double.

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 displays in the instrument cluster, the indicator lamp in the hazard warning system button (N72/1s5) is actuated by the SAM control unit via battery sensor LIN (LIN B15).

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

The hazard warning flasher function comprises 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 flashing for emergency braking 

Function sequence for hazard warning flashing for 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 transmits the vehicle speed to the SAM control unit via the interior CAN.

This function 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.

Additional function requirements for hazard warning flashing for crash recognition 

Function sequence for hazard warning flashing in the event of crash detection 

A crash sensor is integrated into the SAM control unit.

If this detects a crash event during a timeout period of the supplemental restraint system control unit, the SAM control unit initiates the hazard warning flashing function by outputting the flasher frequency over the interior CAN. This serves to avoid any inadvertent activation of the local crash sensor.

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 for feedback from locking/unlocking the central locking (CL [ZV]) (except CODE 494 (USA version) and except CODE 460 (Canada version)) 

Upon locking/unlocking the CL [ZV], the electronic ignition lock control unit sends the status of the CL [ZV] via 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 Acoustic feedback also occurs in accordance with the flashing cycles by means of actuating the left horn (H2) and right horn (H2/1).

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

When an ATA alarm is triggered, the SAM control unit initiates the hazard warning flasher function through 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.

  Electrical function schematic, turn signal light actuation   PE82.10-P-2055-97NAA
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