Headlamp control, function - GF82.10-P-2009LE
MODEL 221.0/1 up to 31.5.09 except CODE (615) Bi-xenon headlamp unit with integrated curve illumination except CODE (616) Bi-xenon headlamp unit with integrated asymmetric curve illumination as of model year 2009/YoM 08
Function requirements, driving lights actuation, general
- No overvoltage or undervoltage (operating voltage range U ≥ 7 ≤17.5 V)
Driving lights actuation, general
Driving lights actuation includes all functions which serve the optimum illumination of the road while driving.
During driving light actuation, the standing/parking lights actuation is active, this is described in a separate document.
The driving lights actuation function is comprised of the following subfunctions:
- Low beam actuation function sequence
- High beam actuation function sequence
- Daytime running lights actuation function sequence
- Auto on/off headlamps function sequence
- Headlamp range adjustment function sequence (HRA [LWR])
Additional low beams actuation function requirements
- Circuit 15 On
Low beam actuation function sequence
Turning the rotary light switch (S1) to the "manual driving lights" switch request actuation of the low beams.
The EIS control unit (N73) transmits circuit 15 status to the front SAM control unit with fuse and relay module (N10/1) via the interior CAN (CAN B).
The upper control panel control unit (N72/1) reads in the status of the rotary light switch via the instrument panel LIN (LIN 1) and transmit it to the front SAM control unit, when then actuates the left low beams (E1e2) and right low beams (E2e2).
Additional function requirements, high beam actuation
- For high beams function: circuit 15 and low beams On
- For headlamp flasher function: circuit 15R On
High beam actuation function sequence
The high beams actuation is comprised of the following subfunctions:
- Function sequence for high beams
- Headlamp flasher function sequence
Function sequence for high beams
The high beams actuation is requested by pressing the combination switch (S4) forward.
The switch position of the combination switch is read in directly by the steering column tube module (N80), sent to the chassis (CAN E) and forwarded by the central gateway control unit (N93) via the interior CAN to the front SAM control unit.
The front SAM control unit receives it and actuates the left high beam (E1e1) as well as the right high beam (E2e1) and then forwards the "high beam actuation active" status via the interior CAN. The central gateway control unit routes it via the central CAN (CAN F) to the instrument cluster (A1), which then actuates the high beam indicator lamp (A1e3).
Headlamp flasher function sequence
The function sequence and signal path for the headlamp flasher function correspond to that of the high beam function. To request the headlamp flasher function, the combination switch must be pulled backward. The high beams actuation remains active for as long as the combination switch is held in this position.
On vehicles with code (460) Canada version or code (494) USA version, the high beams may not be actuated simultaneously with the front fog lamp actuation.
The current incoming request has priority.
Additional function requirements, daytime running lights actuation
- Engine running (circuit 61 On) n > 300 rpm or vehicle speed v > 3 km/h
- Function activated via the instrument cluster
- Exterior lights OFF "0"
- Auto on/off headlamps "AUTO"
- "Left parking light" or "Right parking light" (can be coded)
Daytime running lights actuation function sequence
The request for the daytime running lights function is output depending on the country coding or activated manually by the instrument cluster on the central CAN.
The status of circuit 61 is provided by the CDI control unit (N3/9) (on diesel engine) or by the motor electronics control unit (N3/10) (on gasoline engine) on the chassis CAN.
Information about the vehicle speed is made available by the instrument cluster on the central CAN.
The central gateway control unit routes all relevant information via the interior CAN to the front SAM control unit. The front SAM control unit receives it and actuates the low beams.
On vehicles with code (460) Canada version, the low beams are actuated at a voltage of U = 13.2 V if the rotary light switch is in position "AUTO" and the rain/light sensor (B38/2) set to "day" signal. When the vehicle is at a standstill the daytime running lights function is deactivated following the expiration of a time interval of t = 3 minutes.
On vehicles with code (494) USA version, the daytime running lamp function is deactivated as soon as the rotary light switch is in the "Parking light" or "Manual driving light" position. On vehicles with code (460) Canada version, the "Manual driving light" position is sufficient.
The daytime running lights function has a higher priority than the auto on/off headlamps function.
In countries with legal daytime running light requirements, only the headlamp flasher is permissible but not the high beams. The high beams are only permissible when the driving lights are manually switched on using the rotary light switch.
Additional function requirements, auto on/off headlamps
- Engine running (circuit 61 On) n > 300 rpm or vehicle speed v > 3km/h
- Rotary light switch to position "AUTO"
- Rain/light sensor signals "Darkness detected"
Auto on/off headlamps function sequence
The auto on/off headlamps function is no more than a convenience system and does not exempt the driver from following the operating instructions in the road traffic regulations. With auto on/off headlamps, low beam actuation is switched on or off depending on the ambient brightness. The auto on/off headlamps function can be switched on or off via the rain/light sensor or the activities of the wiper system.
Journey commencement:
- Transmitter key (A8/1) removed Standing lights/low beams OFF
- Circuit 15C ON Standing lights/low beams OFF
- Circuit 15R ON Standing lights ON
- Circuit 15 ON Standing lights ON
- Terminal 61 ON standing lights/low beams ON (high beams permissible)
End of journey:
- Terminal 61 ON standing lights/low beams ON (high beams permissible)
- Circuit 15R ON Standing lights ON
- Circuit 15C ON Standing lights ON
- Transmitter key disconnected Standing lights/low beams OFF
The standing lights are switched off, as soon as the driver door is opened with the transmitter key (circuit 15C) inserted.
Circuit status c. 61 is provided by the CDI control unit or ME-SFI control unit to the chassis CAN.
Information about the vehicle speed is made available by the instrument cluster on the central CAN.
The central gateway control unit routes all relevant information via the interior CAN to the front SAM control unit.
The ambient brightness is recorded by the rain/light sensor.
The overhead control panel control unit (N70) reads in the rain/light sensor data and forwards them over the interior CAN to the front SAM control unit.
If darkness is recognized the front SAM control unit actuates the low beams.
If the windshield wiper system is activated for t = 20 s with a wipe cycle time of t < 6 s, the front SAM control unit activates low beam actuation. If there are no wipe cycles for t 60 s, low beam actuation is deactivated.
Auto on/off headlamps switch-off conditions:
In the event of rain/light sensor failure, the auto on/off headlamps are not deactivated until the engine is switched off. When the vehicle is being driven through a tunnel and if the wiper start suppression function is active, the auto on/off headlamps function remains active. If the wiper start suppression function is canceled, the auto on/off headlamps function remains active for an additional t = 60 s.
Additional headlamp range adjustment function requirements
- Driving lights On (low beam/high beam)
Headlamp range adjustment (HRA [LWR]) function sequence
The headlamp range adjustment is installed as passive safety equipment in vehicles fitted with halogen headlamps to prevent them from dazzling oncoming traffic.
The vehicle headlamp range is controlled via the suspension. The vehicle level is controlled in such a way that the headlamp range is always within the legal limit.
The left headlight unit (E1) and the right headlight unit (E2) does not have any motors for controlling the headlamp range.
| Electrical function schematic for driving light actuation | PE82.10-P-2059-97SAA | ||
| Instrument cluster, component description | A1 | GF54.30-P-6000LE | |
| Component description for CDI control unit | N3/9 On engine 629 in model 221 |
GF07.16-P-6000OA | |
| On engine 642 in model 221 | GF07.16-P-6000OHL | ||
| ME-SFI [ME] control unit, component description | N3/10 With engine 156 |
GF07.61-P-6000MAS | |
| With engine 272 except engine 272.974 | GF07.61-P-6000MIS | ||
| With engine 272.974 | GF07.61-P-6000MEH | ||
| On engine 273 | GF07.61-P-6000MLS | ||
| With engine 275 | GF07.61-P-6000MOS | ||
| Front SAM control unit with fuse and relay module, component description | N10/1 | GF54.21-P-6070LE | |
| Overhead control panel control unit, component description | N70 | GF82.20-P-5216LE | |
| Upper control panel control unit, component description | N72/1 | GF54.21-P-6040LE | |
| Component description for EIS [EZS] control unit | N73 | GF80.57-P-6003LE | |
| Component description for steering column tube module | N80 | GF54.21-P-6050LE | |
| Central gateway control unit, component description | N93 | GF54.21-P-4170LE |