Part 2 of 2

Additional function requirements for Keyless-Go control/ warning messages (with code (889) Keyless Go)
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for Keyless-Go control/warning messages (with code (889) Keyless Go)
If, during a start attempt, the KEYLESS-GO control unit (N69/5) does not detect a valid transmitter key (A8/1) or if the electronic selector lever module control unit (N15/5) (for transmission 722.6) or the intelligent servo module for DIRECT SELECT (A80) does not send the status "selector lever in position P or N", a chime is sounded and a corresponding messages is shown on the multifunction display.
The relevant information for this is sent by the KEYLESS-GO control unit over the interior CAN to the instrument cluster.

Additional function requirements for stationary heater control/ warning messages (with code (228) Stationary heater)
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for stationary heater control/warning messages (with code (228) Stationary heater)
The stationary heater can be programmed in the "Stationary heater" menu in the instrument cluster (e.g. starting time or lead time). The instrument cluster actuates the stationary heater unit (A6) t = 60 mins. before the start of the lead time over the body CAN at the specified time. If the stationary heater control unit (A6n1) detects a fault, it sends corresponding information over the body CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

Additional function requirements for AIRMATIC control unit indicator/warning messages (with code (489) AIRMATIC (air suspension with continuously adjustable damping) or code (488) Steel/air suspension)
^ Circuit 61 ON (signal supplied by CDI control unit or ME-SFI [ME] control unit)

Function sequence for AIRMATIC control unit indicator/ warning messages (with code (489) AIRMATIC (air suspension with continuously adjustable damping) or code (488) Steel/air suspension)
If faults or system malfunctions are recognized by the AIRmatic control unit (N51/3) it sends corresponding information over the chassis CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.
There are various system messages or warning messages with different fault priorities.

If several faults exist at the same time, several fault messages will be issued accordingly.
Depending on the given situation, text messages can be shown on the multifunction display:

Additional function requirements for support system indicator/ warning messages
^ Corresponding Assist System function activated

Function sequence for support systems indicator/warning messages
The assist system warning messages function is made up of the following component functions:
^ Function sequence for ATTENTION ASSIST display
^ Function sequence for automatic lane recognition display (with code (476) Automatic lane recognition)
^ Function sequence for displaying Active Lane Keeping Assist (with code (238) Active Lane Keeping Assist)
^ Function sequence for Speed Limit Assist display (with code (513) Speed Limit Assist)
^ Function sequence for Adaptive Highbeam Assist display (with code (608) Adaptive Highbeam Assist)
^ Function sequence for Blind Spot Assist warning messages (with code (234) Blind Spot Assist)
^ Function sequence for Active Blind Spot Assist warning messages (with code (237) Active Blind Spot Assist)

Function sequence for ATTENTION ASSIST display
Attention Assist monitors the activities of the driver and recognizes fatigue or increasing inattention (e.g. on long, monotonous journeys on freeways and highways) by evaluating the driving behavior. In the first t = 20 min. of monotonous driving individual parameters and a warning threshold are determined by the driver.

If driver fatigue or increasing inattention is recognized, the Electronic Stability Program control unit sends a warning message request through the chassis CAN to the instrument cluster.

The instrument cluster receives this information and then issues a corresponding message over on the multifunction display and actuates the warning buzzer.

Function sequence for automatic lane recognition display (with code (476) Automatic lane recognition)
The automatic lane recognition recognizes when lane marking is driven over and warns the driver in certain situations before the lane is exited.
The multifunction display shows the status and warning readiness of the automatic lane recognition. The multifunction camera (A40/11) sends corresponding information over the chassis CAN to the instrument cluster for this purpose. The instrument cluster receives this data and then issues corresponding messages on the multifunction display

Function sequence for displaying Active Lane Keeping Assist (with code (238) Active Lane Keeping Assist)
The Active Lane Keeping Assist detects when lane markings are crossed over and warns the driver in certain situations by means of a warning system in the steering wheel when the lane is exited. If the warning proves ineffective, intervention by the brake system is authorized to move the vehicle back to the calculated driving lane.

To this end, the multifunction camera sends corresponding information over the chassis CAN to the video and radar sensor system control unit and forwards it to the instrument cluster. In the instrument cluster the current status and the warning readiness are constantly displayed on the multifunction display.

Function sequence for Speed Limit Assist display (with code (513) Speed Limit Assist)
The Speed Limit Assist records detects the speed limits for the stretch driven on by the vehicle.
These are shown on the multifunction display in the form of a traffic sign. The multifunction camera sends corresponding information over the chassis CAN to the instrument cluster for this purpose.
The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

Function sequence for Adaptive Highbeam Assist display (with code (608) Adaptive Highbeam Assist)
The Adaptive Highbeam Assist regulates the headlamp range to match the distance to the next, preceding or oncoming vehicle. If a road user is not detected, the Adaptive Highbeam Assist automatically activates the high beam. The multifunction display shows the status of the Adaptive Highbeam Assist by showing a symbol in the multifunction display.

Function sequence for Blind Spot Assist warning messages (with code (234) Blind Spot Assist)
The Blind Spot Assist monitors the rear area of the vehicle using short range radar and notifies the driver, where applicable, that an intended lane change (flasher operating) at the time in question is not advisable. System readiness and system messages are indicated to the driver (vehicle detected in blind spot) through lighting up the left Blind Spot Assist readiness and warning indicator (M21/1e2) in the left outside mirror (M21/1) or the right Blind Spot Assist readiness and warning indicator (M21/2e2) in the right outside mirror (M21/2).
If, despite the Blind Spot Assist warning lamp lighting up, the driver still attempts to change lane and indicates this by operating the combination switch (S4) (operates flasher), a one-time double-warning tone is issued by the instrument cluster's warning buzzer

Corresponding system faults are also shown on the multifunction display.
The request to issue warnings and fault messages is sent by the radar sensors control unit (up to 31.5.10) over the chassis CAN to the instrument cluster or the right rear bumper intelligent radar sensor (A86/2b6) and the left rear bumper intelligent radar sensor (A86/2b5) (as of 1.6.10) over the front end CAN (CAN G), front SAM control unit and the chassis CAN to the instrument cluster.

Function sequence for Active Blind Spot Assist warning messages (with code (237) Active Blind Spot Assist)
The Active Blind Spot Assist is based on the functionality of the Blind Spot Assist and it can also initiate interventions by the brake system, taking the vehicle surroundings into consideration. To this end, the road space in front of the vehicle is monitored to avoid any collisions with oncoming traffic or stationary obstacles. Active interventions by the brake system are conducted on a wheel-specific basis and exert a corrective influence on the vehicle.

If a risk of collision is detected with vehicles that are in the blind spot or in the road space in front of the vehicle, then an accident can be avoided or the consequences of the accident weakened. The video and radar sensor system control unit sends the system readiness status or the request to issue warning and fault messages over the chassis CAN to the instrument cluster.

Night View Assist warning messages function sequence (with code (610) Night View Assist)
The Night View Assist control unit (N101) monitors the Night View Assist function. If the Night View Assist control unit detects a fault or malfunction, it forwards corresponding data over the chassis-CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

Function sequence for "RACE START" warning messages (model 212.077/277)
The "RACE START" function enables a sporty start off, as under motor racing conditions.
The driver is instructed on the multifunction display to perform certain activities required for execution of the function. Malfunctions are also shown on the multifunction display. The information required for this is sent by the transmission mode control unit over the chassis CAN to the instrument cluster.

Additional function requirements for AHE warning message (with code (550) Trailer hitch)
^ Circuit 15 ON (provided by electronic ignition lock control unit)
^ Trailer detected

Function sequence for trailer hitch warning message (with code (550) Trailer hitch)
The trailer recognition control unit (N28/1) monitors the status of the trailer. If the ball neck is not locked, the trailer recognition control unit sends a corresponding signal over the interior CAN to the instrument cluster. The instrument cluster receives this signal and issues a corresponding message over the multifunction display.

Memory adjustment control messages function sequence (with code (275) Memory package for electrically adjustable front seats)
The instrument cluster outputs an acknowledgment tone when a memory position is stored.

To this end, the driver seat control unit (N32/1) or the front passenger seat control unit (N32/2) sends a corresponding request over the interior CAN to the instrument cluster.

Additional function requirements for audio/communication/ navigation control messages
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for audio/communication/navigation control messages
The multifunction display shows the information from the audio systems installed in the vehicle.
Depending on the equipment specification, additional navigation information or communication-relevant information (e.g. network provider, telephone book entries) is shown on the travel distance display or the multifunction display.

The instrument cluster receives all relevant information from the installed audio components over the interior CAN.
- Radio (A2) (with code (510) Audio 20 with CD changer or with code (523) MB Audio 20 radio)
- Radio with auto pilot system (A2/56) (with code (511) Audio 50 APS incl. DVD changer or code (525) MB Audio 50 APS radio)
- COMAND controller unit (A40/3) (with code (512) COMAND APS incl. DVD changer or code (527) COMAND APS with single DVD drive (with navigation) or code (528) COMAND incl. DVD changer)

Additional function requirements for parking assist control messages (with code (220) PARKTRONIC or code (230) Exclusive parking assist)
^ Vehicle speed v < 40 km/h
^ No trailer operation
^ No ESP and antilock brake system (ABS) control intervention function within a period of t = 5 s

Function sequence for parking assist control messages (with code (220) PARKTRONIC or code (230) Exclusive parking assist)
The parking assist system shows possible parallel parking spaces in the multifunction display after it has measured them.
If the system measures a possible parking space, a white highlighted "P" symbol appears in the multifunction display. If the parallel parking space is deemed suitable, a blue highlighted "P" symbol appears with a directional arrow. The PARKTRONIC control unit (N62) transmits the corresponding information via the chassis CAN to the instrument cluster for this purpose.
When subsequently parking, steering instructions are given to the driver and the current position of the vehicle relative to the parking space is visualized. Additionally, the chime goes off when approaching an obstacle.

Additional function requirements for wiper system control messages (model 212.2)
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for wiper system control messages (model 212.2)
The active rear wiper interval function is shown as a symbol in the multifunction display.
The front SAM control unit sends the "rear wiper interval active" status" over the interior CAN to the instrument cluster.

Additional function requirements for exterior lighting (ABL) warning messages
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Exterior lighting (ABL) function sequence
Visual feedback of switched on low beams is provided by the low beams indicator lamp (A1e67).

Visual feedback of activated high beams is provided by the high beams indicator lamp (A1e3). The front SAM control unit sends the high beam and low beam status over the interior CAN to the instrument cluster. The function of the exterior lights (ABL) components is permanently monitored. If a fault is detected on a component, the monitoring control unit sends corresponding information over the interior CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

The following control units monitor the function of the exterior lights (ABL) components:
- Front SAM control unit
- Rear SAM control unit
- Left front door control unit (N69/1)
- Right front door control unit (N69/2)
- On vehicles with code (550) Trailer hitch.
- Trailer recognition control unit (trailer lighting)

- Additionally with code (615) Bi-xenon headlamp unit with integrated curve illumination or code (616) Bi-xenon headlamp unit with integrated asymmetrical curve illumination or code (621) Intelligent Light System (left-hand traffic) or code (622) Intelligent Light System (right-hand traffic):
- Left xenon light control unit (E1n1)
- Right xenon light control unit (E2n1)

The xenon light control units monitor the functions of the actuated components. If a xenon light control unit detects a fault or a failure of the relevant component, it sends corresponding information to the front end-CAN (CAN G). The front SAM control unit routes this via the chassis-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 light ON (circuit 58 ON)
^ Transmitter key not inserted (circuit 15C OFF)

Lights on reminder function sequence
If the driver door is opened when the standing lights are switched on and with circuit 15C OFF, the instrument cluster actuates the warning buzzer and issues a corresponding message on the multifunction display. The front SAM control unit sends the "standing lights ON" status and the left front door control unit sends the "driver door opened" status over the interior CAN to the instrument cluster.

If the transmitter key is removed from the electronic ignition lock control unit when the rear fog lamp actuation is active, and then the driver door is opened, the instrument cluster actuates the warning buzzer and issues a "Switch off lights" message over 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 at a speed v > 3 km/h an open door, an open engine hood (with code (551) Antitheft alarm system (ATA [EDW])) or an open trunk lid (model 212.0) or an open liftgate (model 212.2) is recognized, the instrument cluster issues an acoustic warning and a corresponding message is shown on the multifunction display.

The instrument cluster reads in the following information over the interior CAN for the output of the door warning function:
- Status of left front door rotary tumbler switch (A85s1), supplied by the left front door control unit
- Status of right front door rotary tumbler switch (A85/1s1), supplied by the right front door control unit
- Status of left rear door rotary tumbler switch (A85/3s1) and right rear door rotary tumbler switch (A85/4s1) provided by rear SAM control unit
- Status of the engine hood antitheft alarm system switch (S62) (with code (551) Antitheft alarm system (ATA [EDW])) supplied by the rear SAM control unit
- Status of trunk lid rotary tumbler switch (M14/7s1) (model 212.0) provided by rear SAM control unit
- Status of liftgate rotary tumbler switch (M14/7s1) (model 212.2) provided by rear SAM control unit

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

Parking brake warning function sequence
The status of the parking brake is monitored by the parking brake indicator switch (S12).

If the parking brake indicator switch is actuated at a speed of v > 5 km/h, the instrument cluster actuates the brake fluid and parking brake warning lamp (A1e7) and issues a corresponding message on the multifunction display. The status of the parking brake indicator switch is read by the front SAM control unit and sent over the interior 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)

Function sequence for speed warning (with code (623) Gulf States version)
At speeds of v > 120 km/h the instrument cluster actuates the warning buzzer and issue a corresponding message on the multifunction display.

The acoustic warning is disabled at speeds of v < 117 km/h.

Additional function requirements for coolant level and coolant temperature warning messages
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for coolant level and coolant temperature warning messages
The coolant level in the expansion reservoir is monitored by the coolant level switch (S41). The status of the coolant level switch is read in by the front SAM control unit.
If the coolant level is too low the front SAM control unit sends a corresponding signal over the interior CAN to the instrument cluster. 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 CDI control unit or ME-SFI [ME] control unit imports the signal of the coolant temperature sensor, uses it to calculate the coolant temperature and then sends the corresponding temperature value via the chassis CAN to the instrument cluster. At a coolant temperature of T > 130 °C the instrument cluster issues a warning tone and shows a corresponding message on the multifunction display.

Additional function requirements for engine oil level warning
^ Circuit 15 ON (provided by electronic ignition lock control unit)
^ Engine OFF (circuit 61 OFF, no signal from CDI control unit or from ME-SFI [ME] control unit)

Engine oil level warning function sequence
To monitor the engine oil level, the CDI or ME-SFI [ME] control units reads in the signals from oil level check switch (S43) in the engine oil pan.

If necessary, the CDI control unit or the ME-SFI [ME] control unit sends a corresponding signal via the chassis CAN to the instrument cluster. The instrument cluster receives this signal and issues a corresponding message over the multifunction display.

Additional function requirements for preglow check (with diesel engine)
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for preglow indicator lamp (with diesel engine)
Preglowing is controlled by the CDI control unit. For the period of time in which the preglowing is active, the CDI control unit sends a corresponding signal via the chassis CAN to the instrument cluster. The instrument cluster receives this signal and actuates the preglow indicator lamp (A1e16).

The function of the preglow indicator lamp is monitored by the on-board diagnosis (OBD).

Additional function requirements for transmission control warning messages (transmission 722)
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for transmission control warning messages (Transmission 722)
If faults or malfunctions are detected in the transmission control, the instrument cluster issues corresponding warning messages on the multifunction display.
The following control units monitor the transmission control:
^ Electronic transmission-control control unit (N15/3) (transmission 722.6)
^ Electronic selector lever module control unit
^ Intelligent servo module for DIRECT SELECT (transmission 722.9)
^ Fully integrated transmission control unit (Y3/8n4) (transmission 722.9)

The monitoring control unit sends the request to display a warning message over the drive train CAN (CAN C) to the CDI control unit or to the ME-SFI [ME] control units, which then forwards this over the chassis CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction display.

Additional function requirements for brake pad wear indicator warning messages
^ Circuit 15 ON (provided by electronic ignition lock control unit)

Function sequence for brake wear indicator warning messages
When the wear limit for the brake pads on the front axle is reached, it is detected by the right front brake wear sensor (S10/2). When the wear limit for the brake pads on the rear axle is reached, it is detected by the right rear brake wear sensor (S10/4).

Once the wear limit for the brake pad is reached, the vehicle ground (circuit 31) is sent over the brake pad wear sensors to the front SAM control unit. The front SAM control unit then sends a corresponding signal over the interior CAN to the instrument cluster.
The instrument cluster receives this signal and issues a corresponding message over the multifunction display.

Additional function requirements for brake fluid level warning messages
^ Circuit 15 ON (provided by electronic ignition lock 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 level switch (S11). The status of the brake fluid level switch is read in by the front SAM control unit. If the fluid level is too low the front SAM control unit sends a corresponding signal over the interior CAN to the instrument cluster.

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

Additional function requirements for windshield washer system fluid level warning messages
^ Circuit 15 ON (provided by electronic ignition lock 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 switch (S42). The status of the windshield washer system fluid level switch is read in by the front SAM control unit. If the fluid level is too low the front SAM control unit sends a corresponding signal over the interior CAN to the instrument cluster. 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 is provided by the left turn signal light indicator lamp (A1e1) or the right turn signal light indicator lamp (A1e2).

Additional function requirements for filler cap warning (with code (494) USA version)
^ Circuit 15 ON (provided by electronic ignition lock control unit)
^ v > 0 km/h (calculated by instrument cluster)

Function sequence for filler cap warning (with code (494) USA version)
If the CDI or ME-SFI [ME] control unit detects an open tank cap it transmits a corresponding signal via the chassis CAN to the instrument cluster.
The instrument cluster receives this signal, actuates the fuel reserve warning lamp (A1e4) and issues a corresponding message on the multifunction display.