LEMON Manuals: Even more car manuals for everyone
Home >> Mercedes Benz >> 2012 >> GL350 >> Repair and Diagnosis >> Accessories & Equipment >> Interior/Illumination Lights >> Electrical System - Body - 164 Chassis - 1 Of 8 >> Basic Knowledge >> Turn signal indicator actuation, function >> Turn signal indicator actuation, function - GF82.10-P-3008GM

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

MODEL 164.1 as of model year 2009/YoM 08 model refinement package 

MODEL 164.8, 251.0/1 as of model year 2009/YoM 08 

Turn signal light actuation function requirements, 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 rear SAM control unit (N10/8).

The rear SAM control unit prioritizes all flashing functions and places a flasher frequency with the time period of the bright phase on the interior CAN (CAN B).

Turn signal light actuation is comprised of the following subfunctions:

Additional function requirements, turn signaling 

IMPORTANT The circuit 15 status is sent to the interior CAN by the EZS control unit (N73).

Operational sequence turn indicators 

The turn signaling function is comprised of the following subfunctions:

Function sequence, left turn signal indicator 

The switch position of the combination switch (S4) is read in by the steering column tube module (N80) and made available on the engine compartment CAN (CAN C). The central gateway control unit (N93) forwards this via the interior CAN to the rear SAM control unit.

The rear SAM control unit passes on the request for output of the left turn signaling function as a flasher frequency to the corresponding control units on the interior CAN and actuates the following components:

The front SAM control unit (N10) receives the flasher frequency and actuates the following components:

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

Function sequence, right turn signal indicator 

The switch position of the combination switch is read in by the steering column tube module and made available on the engine compartment CAN. The central gateway control unit forwards this via the interior CAN to the rear SAM control unit.

The rear SAM control unit passes on the request for output of the right turn signaling function as a flasher frequency to the corresponding control units on the interior CAN and actuates the following components:

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

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

IMPORTANT In vehicles without code (460) Canada version and without code (494) USA version, the side marker lamps are usually actuated as well. In vehicles with code (460) Canada version or code (494) USA version, they are switched off after the first dark phase and then actuated in accordance with the flasher frequency.

Function sequence, 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 lies in the actuation and termination of the turn signal procedure.

The turn signal light switch must only be operated briefly (t < 500 ms) in the desired turn signal direction.

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

IMPORTANT Each active function is displayed to the driver through actuation of the left turn signal indicator lamp (A1e1) or right turn signal indicator lamp (A1e2) and the audible turn signal indicator (A1h2) in the instrument cluster (A1). The rear SAM control unit transmits the flasher frequency to the instrument cluster via the interior CAN for this purpose.

In the event of a turn signal light or turn signal lamp failure, the frequencies of the relevant indicator lamp, turn signal and audible turn signal indicator are acoustically doubled in the instrument cluster. The flashing frequency of the turn signal lights and turn signal lamps is retained.

Function sequence, hazard warning flashing 

The hazard warning flashing function is comprised of the following subfunctions:

Function sequence, hazard warning flashing, manual 

The manual hazard warning flashing function is requested by activating the hazard warning system switch (N72/1s5). The status of the hazard warning system switch is read in directly by the upper control panel control unit (N72/1) and made available on the interior CAN.

The function sequence of the hazard warning flasher system function - relative to the signal flow - corresponds to that of turn signaling. However, all turn signal lights and turn signal lamps on the vehicle and on vehicles with code (550) Trailer hitch or code (553) Mechanically folding trailer hitch, are synchronously actuated on trailer. The rear SAM control unit also sends the "hazard warning flashing active" status via the interior CAN to the upper control panel control unit, which then actuates the indicator lamp in the hazard warning system switch.

Depending on the position of the transmitter key (A8/1) in the EZS control unit, the rear SAM control unit issues two duty cycles:

Additional function requirements, hazard warning flashing for airbag deployment 

Function sequence, hazard warning flashing for airbag deployment 

In the event of airbag deployment, the restraint systems control unit (N2/7) sends a corresponding signal to the engine compartment CAN.

The central gateway control unit routes this signal over the interior CAN to the rear SAM control unit.

The rear SAM control unit then initiates the hazard warning flashing system function by sending the flasher frequency to the interior CAN. Following this, all turn signal lights and turn signal lights on the vehicle are actuated synchronously.

This function is deactivated by operating the hazard warning system switch.

Additional function requirements, hazard warning flashing for emergency braking 

Function sequence, hazard warning flashing for emergency braking 

In the event of any emergency braking, the ESP control unit (N47-5) (except model 164.195) or the regenerative braking system control unit (N30/6) (model 164.195) sends a corresponding signal to the engine compartment CAN. The central gateway control unit routes this signal over the interior CAN to the rear SAM control unit. The rear SAM control unit then initiates the hazard warning flashing system function by sending the flasher frequency to the interior CAN. All the turn signal lights and turn signal lamps on the vehicle are actuated synchronously for at least t = 1 s.

The hazard warning flasher for emergency braking is reset if one of the following conditions is met:

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 EZS control unit via the interior CAN.

When the CL is unlocked the rear SAM control unit activates the hazard warning flashing function for one flasher cycle, when locking three flasher cycles are output.

Function sequence for ATA flashing (with code (551) Antitheft alarm system (ATA) [EDW]) 

If the antitheft alarm system is triggered, the rear SAM control unit initiates the hazard warning flashing system function by sending the flasher frequency to the interior CAN. Following this, all turn signal lights and turn signal lights on the vehicle are actuated synchronously.

REFER TO SYSTEM WIRING DIAGRAMS Electrical function schematic, turn signal light actuation Model 164 PE82.10-P-2055-97MAA
Model 251 PE82.10-P-2055-97RAA
  Component description for instrument cluster A1
Model 251, model 164 (except 164.195)
GF54.30-P-6000GM
Model 164.195
* for USA only
GF54.30-P-6000GQH
  Component description for restraint systems control unit N2/7 GF91.60-P-4048GM
  Component description for front SAM control unit N10 GF54.21-P-7010GM
  Component description for rear SAM control unit N10/8 GF54.21-P-7030GM
  Component description for regenerative braking system control unit N30/6
On model 164.195
* for USA only
GF42.22-P-1100GQH
  Component description for ESP control unit N47-5
Model 251, model 164 (except 164.195)
GF42.45-P-5118GM
  Component description for left front door control unit N69/1 GF72.29-P-4141GM
  Component description for right front door control unit N69/2 GF72.29-P-4142GM
  Upper control panel control unit, component description N72/1 GF54.21-P-6040GM
  EZS control unit, component description N73
Model 251, model 164 (except 164.195)
GF80.57-P-6003GM
Model 164.195
* for USA only
GF80.57-P-6003GQH
  Component description for steering column tube module control unit N80 GF54.21-P-6051GM
  Component description for central gateway control unit N93 GF54.21-P-4170GM