Part 2 of 2

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

Exterior lighting (ABL) function sequence
The active high beams and turn signal light actuation is displayed by the indicator lamps in the instrument cluster. The "Active high beams actuation" feedback is indicated by the high beams indicator lamp (A1e3). The "Active turn signal light actuation" feedback is indicated by the left turn signal indicator lamp (A1e1) and the right turn signal indicator lamp (A1e2).
The high beams actuation status is sent by the driver SAM control unit (N10/10) 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 the data and then issues corresponding messages on the multifunction displays. The function of the components in the exterior lights is monitored by the following control units:
- Xenon headlamp control unit (E1n1)
- Xenon headlamp control unit (E2n1)
- Driver-side SAM control unit
- Right SAM control unit (N10/11)
- Rear SAM control unit (N10/8)
- Left door control unit (N69/1)
- Right door control unit (N69/2)

The xenon headlamp control units monitor the functions of the actuated components. If a xenon headlamp control unit detects a fault or a failure of the relevant component, it sends corresponding information to the diagnostic CAN (CAN D).

The central gateway control unit (N93) forwards this over the engine compartment CAN to the instrument cluster. The instrument cluster receives this data and then issues corresponding messages on the multifunction displays.

Additional function requirements for tire pressure loss warning (with code 477) Tire pressure loss warning)
^ Vehicle speed v > 0 km/h (calculated by instrument cluster)

Tire pressure loss warning function sequence (with code (477) Tire pressure loss warning)
A pressure loss at one of the tires is recognized by the change in wheel circumference and the associated change in wheel speed. If the ESP control unit detects a pressure loss at one of the tires, it sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.

Additional function requirements for tire pressure monitor control/warning messages (with code (470) Tire pressure monitor (standard) or code (475) Tire pressure monitor (premium))
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for tire pressure monitor control/warning messages (with code (470) Tire pressure monitor (basis) or with code (475) Tire pressure monitor (premium))
If the TPM [RDK] control unit (N88) detects a pressure loss at one of the tires or system faults, it sends corresponding information over the interior CAN to the instrument cluster.
The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.

Function sequence for emergency call system control/warning messages (with code (359) TELE AID emergency call system)
When the emergency call system control unit (N123/4) detects a fault during a self-test or if the emergency call system is activated, corresponding messages are shown on the multifunction displays. The relevant information is sent by the emergency call system control unit to the diagnostic CAN.
The central gateway control unit forwards this over the interior CAN to the instrument cluster.

Function sequence for memory adjustment control message
The instrument cluster outputs an acknowledgment tone when a memory position is stored.
To this end, the left front seat adjustment control unit with memory (N32/1) or the right front seat adjustment control unit with memory (N32/2) forward a corresponding request over the interior CAN to the instrument cluster.

Additional function requirements for Keyless-Go control/ warning messages (with code (889) Keyless Go)
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for Keyless-Go control/warning messages (with code (889) Keyless Go)
If the KEYLESS-GO control unit (N69/5) does not detect a valid transmitter key (A8/1) during a start attempt or if the electronic selector lever module control unit (N15/5) does not send the "selector lever position P or N" status, then a chime is heard and corresponding messages are shown in the multifunction displays. 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 audio/communication/ navigation control messages
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for audio/communication/navigation control messages
The multifunction displays show 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 right multifunction display. The instrument cluster receives all the relevant information from the COMAND operating, display and controller unit (A40/3) over the interior CAN. The left multifunction display shows the corresponding menu and the right multifunction display the text and symbol-based information.

Additional function requirements for transmission-control control/warning messages
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for transmission-control control/warning messages
The current gear range and the current transmission mode are shown in the right multifunction display. The gear range is shown on the left-hand edge and the transmission mode on the right-hand edge of the multifunction display.

On vehicles with code (428) Steering wheel shift buttons and without code (494) USA version, the selected shift range or the selector lever position ("D" to "P") as well as the selected transmission mode ("C", "S" or "M") are displayed. On vehicles with code (428) Steering wheel shift buttons and without code (494) USA version, the selected shift range or the selector lever position ("D" to "P") as well as the selected transmission mode ("C" or "S") are displayed.

If the electronic transmission control (EGS) control unit (N15/3) (with transmission 722.6) or the fully integrated transmission control unit (VGS) (Y3/8n4) (with transmission 722.9) detects malfunctions or faults in the transmission control, it sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.

Additional function requirements for Active Body Control (ABC) control/warning messages (with code (487) Active Body Control (ABC))
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for ABC control/warning messages (with code (487) Active Body Control (ABC))
If the ABC control unit (N51/2) in the ABC system detects a fault or a malfunction, it sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.

Additional function requirements for engine-control control/ warning messages
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for engine-control control/warning messages
If there is a fault in the diesel fuel injection system, in the ignition system or in the exhaust system, the ME-SFI [ME] control unit sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the information, actuates the engine diagnostic indicator lamp (A1e58) (without code (494) USA version) or the CHECK ENGINE indicator lamp (A1e26) (with code (494) USA version) and forwards corresponding messages over the multifunction displays.

Additional function requirements for Vario roof warning message
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for Vario roof warning messages
If the roll bar Vario roof control unit (N52) detects a fault in the Vario roof control, it sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.

Additional function requirements for lights on reminder
^ Circuit 15C OFF (provided by EIS [EZS] control unit)
^ Circuit 58 ON

Lights on reminder warning function sequence
If at circuit 15C OFF and with the standing lights switched off, the driver door is opened, the instrument cluster actuates the warning buzzer and issues a corresponding message over the multifunction displays.

The active standing lights actuation is sent by the driver SAM control unit and the status of the driver door by the rear SAM control unit to the interior CAN.
If the transmitter key is removed from the EIS [EZS] 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 corresponding message on the multifunction displays.

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 inspection switch (S12). If the parking brake inspection 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 the warning buzzer

If the vehicle speed drops to less than v = 2.5 km/h, the instrument cluster stops actuating the warning buzzer. The status of the parking brake indicator switch is read in directly by the driver-side SAM control unit and sent to the interior CAN.

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

Vehicle speed warning function sequence (with code (623) Arab States of the Gulf version)
At speeds of v > 120 km/h the instrument cluster actuates the warning buzzer and issues corresponding messages on the multifunction displays. The instrument cluster uses the wheel speeds provided by the ESP control unit over the engine compartment CAN to calculate the vehicle speed. At speeds of v < 117 km/h the acoustic warning is disabled.

Additional function requirements for engine oil level warning message
^ Circuit 15 On (provided by EIS [EZS] control unit)
^ Circuit 61 OFF (signal generated by ME-SFI [ME] control unit)

Function sequence for engine oil level warning message
In order to monitor the engine oil level, the oil pan has an oil sensor installed in it (oil level, temperature and quality) (B40) (with engine 275) or the oil level check switch (S43) (with engine 272, 273). The data from the oil sensor or the status of the oil level check switch are read in and evaluated by the ME-SFI [ME] control unit. If necessary, the ME-SFI [ME] control unit sends a corresponding signal over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.

The following messages are issued on the right multifunction display:
- "Check engine oil level" (with engine 272, 273)
- "During refueling stop top up with 1l of engine oil" (with engine 275)
- "Stop vehicle. Engine oil level. Engine off" (with engine 275)
- "Engine oil level. Reduce oil level" (with engine 275
- "Engine oil level. Engine oil level measurement not possible" (with engine 275)

Additional function requirements for brake wear indicator
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for brake wear indicator
The reaching of a wear limit for the front axle brake pads is detected by the right front brake pad contact sensor (S10/2) and the reaching of a 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 brake pads on the front axle is reached, the vehicle mass is switched through to the front passenger-side SAM control unit over the front brake pad contact sensor. When the wear limit for the brake pads on the rear axle is reached, the vehicle mass is switched through to the rear passenger-side SAM control unit over the rear brake pad contact sensor. The corresponding front SAM control unit then sends a signal over the interior CAN to the instrument cluster. The instrument cluster receives this signal and issues a corresponding message over the multifunction displays.

Additional function requirements for brake fluid level warning message
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for brake fluid level warning message
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 driver SAM control unit. If the fluid level is too low the driver 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 and parking brake warning lamp and issues a corresponding message on the multifunction displays.

Additional function requirements for coolant and coolant temperature warning messages
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for coolant and coolant temperature warning messages
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-passenger SAM control unit.

If the coolant level is too low the front-passenger 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 displays. The coolant temperature is recorded by the coolant temperature sensor (B11/4). The ME-SFI [ME] control unit reads in the signal of the coolant temperature sensor, uses it to calculate the coolant temperature and then sends the corresponding temperature value over the engine compartment CAN to the instrument cluster. 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 on the multifunction displays.

Additional function requirements for windshield washer system fluid level warning message
^ Circuit 15 On (provided by EIS [EZS] control unit)

Function sequence for windshield washer system fluid level warning message
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-passenger SAM control unit. If the level is too low the front-passenger 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 displays.

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 indicated by the turn signal indicator lamps.

Additional function requirements for tank cap open warning message (with code (494) USA version)
^ Vehicle speed v > 5 km/h (calculated by instrument cluster)

Tank cap open warning message function sequence (with code (494) USA version)
The ME-SFI [ME] control unit monitors the status of the tank cap. If, after starting a journey, an open tank cap is detected, the CDI control unit or the ME-SFI [ME] control unit issues a corresponding signal over the engine compartment CAN to the instrument cluster. The instrument cluster receives this signal, actuates the fuel reserve warning lamp (A1e4) so it blinks at a frequency of f = 2.5 Hz and shows a corresponding message on the multifunction displays.