Part 2 of 2

Additional function requirements, Speed Limit Assist control messages (with code (513) Speed Limit Assist)
^ Engine running (circuit 61 ON) (sent from ME-SFI [ME] control unit)
^ Vehicle moving forward

Speed Limit Assist control messages function sequence (with code (513) Speed Limit Assist)
The Speed Limit Assist function records the speed limits shown for the stretch being driven on by the vehicle. These are shown in the form of a traffic sign in the multifunction display.
The Speed Limit Assist function status is shown by a symbol in the multifunction display. The display concept distinguishes between the following modes:
- Information mode
- Display mode

Information mode:
In information mode the recognized speed limit can be displayed in the form of a traffic sign for a period of t = 5 s. This information can be acknowledged within this period. The information mode can be switched on or off by the driver.

Display mode:
In display mode the recognized speed limit is displayed permanently until one of the following events occurs:
- Recognition of a new speed limit
- Recognition of a cancel sign
- No identification of a new road sign for a certain distance, depending on the type of road.
- Passing recognized local limits
- Recognition of turning off 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, Adaptive Highbeam Assist control message (with code (608) Adaptive Highbeam Assist)
^ Function enabled in instrument cluster

Adaptive Highbeam Assist control message function sequence (with code (608) Adaptive Highbeam Assist)
The adaptive high beams function is an assistance function in which the range of the xenon bulbs is adapted to the distance o the nearest road user ahead or driving in the opposite direction. The status of the adaptive high beams 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, attention assist control/ warning messages
Vehicle speed v = 80 to 180 km/h (calculated by instrument cluster)

Function sequence for Attention Assist control/warning messages
Attention assist assists the driver on long monotonous trips e.g. on freeways and expressways in a vehicle speed range of v = 80 to 180 km/h.
If attention assist establishes driver fatigue or increasing inattentiveness, it proposes a break. The attention assist assesses driver fatigue or increasing inattentiveness by the analysis of steering ability by means of steering wheel angle signals as well as driving conditions (time of day/night, driving time). In the first t = 20 min. of monotonous driving individual parameters and a warning threshold are determined by the driver. When the warning threshold is reached a visual as well as an acoustic warning message are issued by the instrument cluster.

The regenerative braking system control unit transmits the corresponding request to the instrument cluster via the chassis CAN, central gateway control unit and central CAN.
As a result of this the request to have a break appears in the multifunction display in the instrument cluster and an acoustic warning 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.

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

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 (sent by EIS (EZS) control unit)

Exterior lighting (ABL) function sequence
The function of components relevant to exterior lighting is monitored permanently.

If a defect is established in a component, the monitoring control unit transmits corresponding information on the interior CAN. The central gateway control unit passes on all the relevant information to the instrument cluster via the central CAN. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

The following control units monitor the function of components relevant to exterior lighting:
- Front SAM control unit with fuse and relay module (N10/1)
- Rear SAM control unit
- Door control module front left
- Door control module front right
- Xenon headlamp control unit (E1n1) at left front lamp unit (E1)
- Xenon headlamp control unit (E2n1) at right front lamp unit (E2)

The xenon headlamp control units monitor the extended light 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 for lights on reminder
^ Standing lights ON
^ Driver door OPEN
^ Transmitter key removed

Lights on reminder function sequence
The logic for actuating the lights-on reminder is stored in the instrument cluster. The front SAM control unit transmits the status "Standing lights actuation active" to the instrument cluster via the interior CAN, central gateway control unit and central CAN. The status of the driver door is provided by the left front door control unit on the interior CAN and the status of circuit 15 is sent by the EIS [EZS] control unit to the chassis CAN. The central gateway control unit passes on all the relevant information to the instrument cluster via the central CAN.

The instrument cluster combines this with the status of the headlamp switch-off delay (SWA) function and actuates the warning buzzer accordingly. The message "Switch off lights" appears in the multifunction display.

Standing lights may be on due to low beams having been switched on manually, auto on/off headlamps having been switched on, daytime running lights being on or because they have been switched on manually by means of 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 the rear fog lamp actuation prevents this being automatically activated on the next trip with switched-on low beams.

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

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

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

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 to output the country-dependent seat belt reminder warning:
- Internal:
- Vehicle speed

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

- From Weight Sensing System (WSS) control unit (N110) (with code (494) USA version):
- Front passenger seat occupancy status

- From the left front door control unit:
- Status of left front rotary tumbler switch (A85s1)

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

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

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

- By the rear SAM control unit:
- Left rear seat belt buckle switch status (S68/11)
- Right rear seat belt buckle switch status (S68/12)
- Status of center rear seat belt buckle switch (S68/14) (without code (224) Design individual rear seat system)

The central gateway control unit passes on this information to the instrument cluster via the central CAN.
The way in which the seat belt reminder warning is output depends on whether the seat belt reminder warning is legally required or not and contributes to the assessment by the New Car Assessment Program (NCAP).

NCAP is an assessment program for safety in new vehicles.
- 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 specified by law (European New Car Assessment Program (Euro NCAP)): Europe (Economic Commission for Europe (ECE)), China and Australia.

In countries with seat belt reminder warning specified by law (extended NCAP) the seat belt warning lamp (A1e9) is actuated 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's seat belt is not fitted, the instrument cluster also issues an acoustic warning over the internal warning buzzer. For this the instrument cluster evaluates the status of the driver seat belt buckle switch and seat belt reminder warning. The central gateway control unit passes on this information to the instrument cluster via the central CAN.

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 sea 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. During the output of these acoustic warning phases the seat belt warning lamp is actuated with 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 expiry of acoustic warning phase 1 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 = 1 s. This is then followed by a transition to acoustic warning phase 3.
- Acoustic warning phase 3:
After expiry of 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 the expiry of acoustic warning phase 3 and as of a speed of v ≥25 km/h a loud acoustic warning sounds for a maximum of 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.
- When the vehicle is stationary the vehicle door on the actuating side is opened.

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
- A newly detected ignition sequence as from circuit 61 ON.

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.

Additional function requirements for coolant level and coolant temperature warning
^ Circuit 15 ON (sent by EIS (EZS) control unit)

Function sequence for coolant level and coolant temperature warning
The coolant level in the expansion reservoir is monitored by the coolant level indicator switch (S41).
The status of the coolant level indicator switch is read in by the front SAM control unit.

When the coolant level is too low the front SAM control unit transmits a corresponding signal to the instrument cluster via the interior CAN, central gateway control unit and central CAN. The instrument cluster receives this signal and issues a corresponding message over the multifunction display.
The coolant temperature is recorded by the coolant temperature sensor (B11/4). The ME-SFI control unit reads in the signal from the coolant temperature sensor and transmits the corresponding temperature value on the chassis CAN.
The central gateway control unit passes this on to the instrument cluster via the central CAN.

When a coolant temperature of T > 130 °C is reached the instrument cluster actuates the coolant temperature warning lamp (A1e54) and issues a corresponding message via the multifunction display.

Additional function requirements, engine oil level warning
^ Circuit 15 ON (sent by EIS (EZS) control unit)
^ Circuit 61 Off (no signal sent by ME-SFI [ME] control unit)

Engine oil level warning function sequence
The oil level check switch (S43) is installed in the engine oil pan to monitor the engine oil level. However, the oil level check switch only detects whether the engine oil level is on the minimum or not. The oil level check switch signals are read in directly by the ME-SFI [ME] control unit and evaluated. If necessary the ME-SFI control unit transmits a corresponding signal to the instrument cluster via the chassis CAN, central gateway control unit and central CAN. The instrument cluster receives the signal and issues one of the following messages via the multifunction display:
- "Engine oil level. Stop vehicle. Switch off engine" (red)
- "Check engine oil level during refueling stop" (yellow)

Additional function requirements for brake pad wear indicator warning messages
^ Circuit 15 ON (sent by EIS (EZS) control unit)

Function sequence for brake wear indicator warning messages
The reaching of the wear limit for the front axle brake pads is detected by the right front brake pad contact sensor (S10/2) and the reaching of the wear limit for the rear axle brake pads is detected by the right rear brake pad contact sensor (S10/4). When the wear limit for the front brake pads is reached, the vehicle ground is switched through to the front SAM control unit via the front brake pad contact sensor.
When the wear limit for the rear brake pads is reached, the vehicle ground is switched through to the rear SAM control unit via the rear brake pad contact sensor.
The respective SAM control unit then transmits a corresponding signal via the interior CAN, central gateway control unit and central CAN to the instrument cluster.

The instrument cluster receives this signal, actuates the brake fluid warning lamp and outputs a corresponding message via the multifunction display.

Additional function requirements for brake fluid level warning messages
^ Circuit 15 ON (sent by EIS (EZS) control unit)

Function sequence for brake fluid level warning messages
if the fluid level in the brake fluid reservoir is too low it is detected by the brake fluid check switch (S11).
The status of the brake fluid check switch is read in by the front SAM control unit. When the fill level is too low the front SAM control unit transmits a corresponding signal to the instrument cluster via the interior CAN, central gateway control unit and central CAN. The instrument cluster receives the signal, actuates the brake fluid warning lamp and issues a corresponding message via the multifunction display.

Additional function requirements for windshield washer system fluid level warning messages
^ Circuit 15 ON (sent by EIS (EZS) control unit)

Function sequence for windshield washer system fluid level warning messages
The fluid level in the washer fluid reservoir is monitored by the windshield washer system fluid level indicator switch (S42 The status of the windshield washer system fluid level indicator switch is read in by the front SAM control unit. When the fill level is too low the front SAM control unit transmits a corresponding signal to the instrument cluster via the interior CAN, central gateway control unit and central CAN. The instrument cluster receives this signal and issues a corresponding message over the multifunction display.

Turn signal confirmation function sequence
Acoustic feedback about the active turn signal light actuation is realized by the acoustic turn signal indicator integrated into the instrument cluster.
Visual feedback takes place via the left turn signal indicator lamp and right turn signal indicator lamp.

Additional function requirements for engine-control control/ warning messages
^ Circuit 15 ON (sent by EIS (EZS) control unit)

Function sequence for engine-control control/warning messages
If a fault is present in the injection system, ignition system or exhaust gas system, the ME-SFI control unit transmits a corresponding signal to the instrument cluster via the chassis CAN, central gateway control unit and central CAN. The instrument cluster then actuates the engine diagnosis indicator lamp (A1e58).

Additional function requirements for tank cap warning (with code (494) USA version)
^ Circuit 15 ON (sent by EIS (EZS) control unit)

Function sequence for tank cap warning (with code (494) USA version)
If the rear SAM control unit identifies an open tank cap, it transmits a corresponding signal via the interior CAN, central gateway control unit and central CAN to the instrument cluster.

The instrument cluster receives this signal, actuates the fuel reserve warning lamp (A1e4) so that it flashes and issues a corresponding message via the multifunction display.