Part 2 of 3

Additional function requirements for Attention Assist control/ warning messages (on model 221 as of 1.6.09)
^ Vehicle speed v = 80 up to 180 km/h (calculated by ESP control unit)

Function sequence for Attention Assist control/warning messages
The Attention Assist system supports the driver on long, monotonous journeys, e.g. on freeways and highways in a vehicle speed range of v = 80 up to 180 km/h.
The Attention Assist system recommends taking a break if it diagnoses driver fatigue or increasing inattention. The Attention Assist system assesses the fatigue or increasing inattention of the driver by analyzing steering behavior on the basis of the steering angle signal as well as the journey conditions (time of day, driving time).

The driver's individual parameters and a warning threshold are determined in the first t = 20 minutes of a monotonous journey. The instrument cluster issues a visual as well as acoustic warning message when this warning threshold has been reached. The ESP control unit transmits the corresponding request via the chassis CAN, central gateway control unit and central CAN to the instrument cluster.
The prompt to take a break appears in the multifunction display in the instrument cluster and a warning tone sounds.

An active warning can be confirmed and thus terminated with the OK button on the left multifunction steering wheel button group. The next warning is only possible after t > 15 minutes. The status of the multifunction steering wheel button group is made available to the ESP control unit via the steering LIN (LIN E1), steering column tube module and chassis CAN.

Additional function requirements for automatic lane recognition warning messages (on model 221 as of 1.6.09 with code (476) Automatic lane recognition)
^ Circuit 15 On (provided by EZS control unit)
^ Function enabled via the instrument cluster
^ Radius of curve r >150 m
^ Track width s = 2.2 up to 4.6 m
^ Identifiable lane markings present
^ Vehicle speed v = 60 up to 250 km/h (calculated by instrument cluster)

Function sequence for automatic lane recognition warning messages
The automatic lane recognition function recognizes when the vehicle pulls out of a lane and warns the driver so that he/she can react accordingly.

The traffic in front of the vehicle is recorded and evaluated by the multifunction camera. As soon as a front wheel touches (A40/11) or goes over the road marking, the multifunction camera issues the requirement to perform the haptic warning. This is accomplished by actuating the steering wheel vibration motor (M99).
The current status of the automatic lane recognition function is shown in the multifunction display.

Additional function requirements for Speed Limit Assist control/warning messages (on model 221 as of 1.6.09 with code (513) Speed Limit Assist)
^ Circuit 61 On (provided by CDI control unit or ME-SFI [ME] control unit)
^ Vehicle moving forward

Function sequence for Speed Limit Assist control/warning messages
The Speed Limit Assist function records speed limits shown for the route the vehicle has driven. These are shown in the multifunction display in the form of a road sign.
The Speed Limit Assist function status is shown by a symbol in the multifunction display.
The display concept differentiates between the following modes:
- Reference mode
- Display mode

Reference mode:
In reference mode, the identified speed limit is displayed in the form of a road sign for a period of t = 5 s. This reference can be acknowledged within this period. The reference mode can be switched on or off by the driver.

Display mode:
In display mode, the identified speed limit is permanently displayed until one of the following events occurs:
- Identification of a new speed limit
- Identification of a cancelation sign
- No identification of a new road sign for a certain distance, depending on the type of road.
- Passing identified city limits
- Identification of turning process
- Change of road type

The multifunction camera transmits corresponding requests for the control of the display via the chassis CAN, the central gateway control unit and central-CAN to the instrument cluster.

Additional function requirements for Adaptive Highbeam Assist control message (on model 221 as of 1.6.09 with code (608) Light package for Avantgarde incl. Intelligent Headlamp Control (ECE))
^ Function enabled in instrument cluster

Function sequence for Adaptive Highbeam Assist control message
The adaptive high beam is an assistance function, in which the headlight range of the xenon bulbs is adjusted to the distance o the next road user, either ahead or oncoming.
The status of the adaptive high beam function is shown in the multifunction display. For this purpose, the multifunction camera transmits corresponding information via the chassis CAN, central gateway control unit and central CAN to the instrument cluster.

Additional function requirements for trailer recognition control/warning messages (on model 221 with code (550) Trailer hitch)
^ Circuit 15 On (provided by EIS [EZS] control unit)
^ Trailer detected

Function sequence for trailer recognition control/warning messages
If the trailer recognition control unit identifies a malfunction in the electrical system (e.g. exterior lights) then a corresponding signal is relayed via the interior CAN, central gateway control unit and central CAN to the instrument cluster.
The instrument cluster outputs the respective fault message in the multifunction display.

Additional function requirements for door open reminder warning
^ Vehicle speed v > 3 km/h (calculated by instrument cluster)

Function sequence, door open reminder warning
If an open door, open trunk lid or open engine hood (with code (551) Antitheft alarm system (ATA [EDW])) is detected at a speed of v > 3 km/h, the instrument cluster issues an acoustic warning and a corresponding message is displayed in the multifunction display.
The following control units make the status of the doors, trunk lid and engine hood available on the interior CAN:
- Left door control unit (N69/1) (model 216) or left front door control unit (N69/1) (model 221), left front door status
- Right door control unit (N69/2) (model 216) or right front door control unit (N69/2) (model 221), right front door status
- Left rear door control unit (N69/3), left rear door status
- Right rear door control unit (N69/4), right rear door status
- Rear SAM control unit, trunk lid status and engine hood status

The central gateway control unit relays all relevant information via the central CAN to the instrument cluster.

Additional function requirements for exterior lighting (ABL) warning messages
^ Circuit 15 On (provided by EIS [EZS] control unit)

Exterior lighting (ABL) function sequence
The functions of the relevant exterior lighting (ABL) components are permanently monitored.
If a fault is detected on a component, the monitoring control unit sends a corresponding signal on the interior CAN to the instrument cluster. The central gateway control unit relays all relevant information via the central CAN to the instrument cluster. The instrument cluster receives this data and issues a corresponding message on the multifunction display.
The following control units monitor the function of the relevant exterior lighting (ABL) components:
- Front SAM control unit with fuse and relay module (N10/1)
- Rear SAM control unit
- Left door control unit or front left door control unit
- Right door control unit or front right door control unit
- Trailer recognition control unit (on model 221 with code (550) Trailer hitch)

On model 216, model 221 (as of 1.6.09) and model 221 with code (615) Bi-xenon headlamp unit with integrated curve illumination or code (616) Bi-xenon headlamp unit with integrated asymmetrical curve illumination) (up to 31.5.09), the xenon headlamp control unit (E1n1) on the left front lamp unit (E1) and the xenon headlamp control unit (E2n1) on the right front lamp unit (E2) monitor the cornering lights and dynamic curve illumination functions. If a xenon headlamp control unit identifies a fault or the failure of a relevant component, it sends corresponding information via the front end CAN (CAN G), central gateway control unit and central CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

Additional function requirements, lights on reminder warning
^ Standing lights ON
^ Driver door OPEN
^ Transmitter key removed

Lights on reminder function sequence
The logic for actuating the lights on reminder warning function is stored in the instrument cluster. The front SAM control unit transmits the "standing light active" status via the interior CAN, central gateway control unit and central CAN to the instrument cluster. The driver door status is provided by the left door or front left door control unit on the interior CAN and the current status of circuit 15 is provided by the EZS control unit on the chassis CAN. The central gateway control unit relays all relevant information via the central CAN to the instrument cluster.
The instrument cluster links this with the status of the headlamp switch-off delay (SWA) and actuates the warning buzzer accordingly. The message "switch light off" appears in the multifunction display.

The standing lights may be switched on because the low beams have been manually switched on, because of the auto on/off headlamps, the daytime running lights or manually via the rotary light switch (S1).
If the standing lights have been activated by manually switching on the low beams, the auto on/off headlamps or the daytime running lights and the driver door is then opened with a transmitter key in the EIS [EZS] control unit, the standing lights are switched off. If the transmitter key is removed from the EIS [EZS] control unit when the rear fog light actuation is active, and then the driver door is opened, the instrument cluster actuates the warning buzzer and issues a corresponding message on the multifunction display. The request to deactivate rear fog light actuation prevents the rear fog light actuation from being activated automatically the next time the vehicle is driven with the low beams switched on.

Additional function requirements for parking brake on reminder warning
^ Vehicle speed v > 5 km/h (calculated by instrument cluster)

Parking brake warning function sequence
If the electric parking brake switch (S76/15) is activated at a speed of v > 5 km/h or the electric parking brake controller unit (A13) detects a fault in the system, the instrument cluster actuates the electric parking brake warning light (red) and issues a chime as well as a corresponding message in the multifunction display The electric parking brake controller unit reads in the status of the electric parking brake switch and transmits this as well as system fault messages via the front end CAN, central gateway control unit and central CAN to the instrument cluster.

Additional function requirements for speed warning (with code (623) Gulf States version)
^ Vehicle speed v > 120 km/h (calculated by instrument cluster)

Vehicle speed warning function sequence
At speeds of v > 120 km/h the instrument cluster issues a corresponding message on the multifunction display and a chime. The instrument cluster calculates the vehicle speed from the wheel speeds, which are provided by the ESP control unit on the chassis CAN and relayed by the central gateway control unit on the central CAN.

Additional function requirements, national seat belt reminder warning
^ Circuit 61 On (provided by CDI control unit or ME-SFI [ME] control unit)
^ Circuit 15 On (with code (498) Japan version) (provided by EZS control unit)

National seat belt reminder warning function sequence
If, immediately prior to starting a journey or during a journey, a seat belt is detected to be not fitted, the instrument cluster issues a country-specific optical and acoustic seat belt reminder warning. The instrument cluster reads out the following information for issuing a country-specific seat belt reminder warning:
- Internal:
- Vehicle speed

- From the restraint systems control unit:
- Driver seat belt buckle and seat belt reminder warning switch status (S68/1)
- Front passenger seat belt buckle and seat belt reminder warning switch status (S68/2) (with recognized seat occupation)
- Front passenger seat occupation status (without code (494) USA version)

- From the Weight Sensing System (WSS) control unit (N2/13) (on model 221 with code (494) USA version up to 31.8.08):
- Front passenger seat occupancy status

- Weight Sensing System (WSS) control unit (N110) (model 221 with code (494) USA version as of 1.9.08, model 216 with code (494) USA version):
- Front passenger seat occupancy status

On model 216:
- From the left door control unit:
- Left rotary tumbler switch (A85s1)

- From the right door control unit:
- Right rotary tumbler switch (A85/1s1)

On model 221:
- From the left front door control unit:
- Left front rotary tumbler switch (A85s1)

- From the right front door control unit:
- Right front rotary tumbler switch (A85/1s1)

- From the left rear door control unit:
- Left rear rotary tumbler switch (A85/3s1)

- From the right rear door control unit:
- Right rear rotary tumbler switch (A85/4s1)

- From the rear SAM control unit with fuse and relay module:
- Left rear seat belt buckle switch (S68/11)
- Right rear seat belt buckle switch (S68/12)
- Center rear seat belt buckle switch (S68/14) (model 221)

The central gateway control unit relays this information via the central CAN to the instrument cluster.
The manner of how the seat belt reminder warning is issued differs in whether the seat belt reminder warning is prescribed by law or not and is incorporated into the assessment through the New Car Assessment Program (NCAP).

NCAP is an assessment program for safety in new vehicles in:
- Countries with seat belt reminder warning prescribed by law (extended NCAP): Japan, USA, Canada, Arab States of the Gulf and Korea.
- Countries without seat belt reminder warning prescribed by law (European New Car Assessment Program (Euro-NCAP)): Europe (Economic Commission for Europe (ECE)), China and Australia.

In countries in which the seat belt reminder is prescribed by law (extended NCAP), the seat belt warning lamp (A1e9) is activated for a time interval of t = 6 ±2 s. It is irrelevant here whether the driver seat belt is fitted or not.

If the driver is not wearing the seat belt, the instrument cluster also issues an acoustic warning over the internal warning buzzer. To this end, the instrument cluster evaluates the status of the driver seat belt buckle and seat belt reminder warning switch. The central gateway control unit relays this information via the central CAN to the instrument cluster.

If the driver seat belt is fitted during this time interval, the acoustic warning is canceled.

An assessment of whether the front passenger seat belt is fitted or not given during this time interval.
Only after the time interval of t = 6 s has expired, does the assessment of both seat belts occur.

In countries in which the seat belt reminder warning is not prescribed by law, the seat belt warning lamp is only actuated during the indicator lamp test.
Immediately after detecting engine running (circuit 61) both the status of the driver seat belt buckle and seat belt reminder warning switch as well as the status of the front passenger seat belt buckle and seat belt reminder warning switch are assessed. If a seat belt is defined to not be fitted, the instrument cluster actuates the seat belt warning lamp.
If the vehicle starts to move, when it reaches a speed of v ≥25 km/h, further successive acoustic warnings are issued. Three or four acoustic warnings are issued in accordance with the seat belt reminder warning. While they are being issued the seat belt warning lamp is actuated at a frequency of f = 1 Hz.

- Acoustic warning phase 1: As the vehicle starts to drive off, acoustic warning phase 1 also starts in the background. When a speed of v ≥25 km/h is reached, a quiet acoustic warning is sounded at an interval of t = 2 s. The acoustic warning phase 1 last for a maximum t = 20 s. This is then followed by a transition to acoustic warning phase 2.
- Acoustic warning phase 2: After running the acoustic warning phase 1 and from a speed of v ≥25 km/h a quiet acoustic warning is sounded for maximum t = 20 s at an interval of t = 1 s. This is then followed by a transition to acoustic warning phase 3.
- Acoustic warning phase 3: After running acoustic warning phase 2 and as from a speed of v ≥25 km/h a quiet acoustic warning is sounded for maximum t = 20 s at an interval of t = 0.4 s. This is then followed by a transition to acoustic warning phase 4.
- Acoustic warning phase 4 (EURO NCAP only): After running acoustic warning phase 3 and as from a speed of v ≥25 km/h a quiet acoustic warning is sounded for maximum t = 93 s at an interval of t = 0.5 s.

Cancellation of seat belt reminder warning:
- The last acoustic warning phase is fully completed.
- The belt was fitted during the active seat belt reminder warning.
- The driver door or front passenger door is opened in a stationary vehicle.

Seat belt reminder warning cancelation as of 1.9.08:
If vehicle is brought to a standstill (v = 0 km/h) when the seat belt reminder warning is active and if the vehicle door of the triggering side is opened, the seat belt reminder warning is terminated.

Seat belt reminder warning reactivation:
- Seat belt release has been detected again.
- If the vehicle is at a standstill and the driver or front passenger door is opened and then closed again
- An ignition sequence is detected again as of circuit 61 On or circuit 15 On (with code (498) Japan version)

The seat belt reminder warning for the rear passengers is realized by monitoring the total number of belt tabs inserted into the seat belt buckles in the rear.
If this situation alters during a journey or at vehicle standstill, without a rear door being opened, the instrument cluster actuate the seat belt warning lamp and the warning buzzer to issue the seat belt reminder warning.
If the seat belt reminder warning is issued when the vehicle is moving, it is displayed again another t = 30 s when the vehicle is determined to be at rest. This is contingent on a change in the door status for the left rear door or the right rear door while the vehicle is at a standstill.

The seat belt reminder warning, however, does not have an effect on the deployment of the restraint equipment, it only serves as information for the driver.