Part 1 of 2
GF54.30-P-2001RI Indicator/warning Messages, Function
- except CODE (P99) Special model "AMG Black Series"
General function requirements
^ Instrument cluster (A1) activated
Indicator/warning messages, general
The instrument cluster indicator and warning messages notify the driver about the current states of the systems installed in the vehicle.
The instrument cluster can issue indicator and warning messages in the following ways:
- Optical issue of indicator and warning messages
- Acoustic output of indicator and warning messages
Visual indicator/warning messages:
The visual indicator and warning messages are displayed using the following instrument cluster components:
- Left multifunction display (A1p13)
- Right multifunction display (A1p15)
- Various indicator/warning lamps
Audible indicator/warning messages:
The acoustic indicator and warning messages are issued using the following instrument cluster components:
- Internal speaker "chime" (activated at a frequency of f = 1 Hz)
- Warning buzzer (A1h1) (activated at a frequency of f = 2.5 Hz)
- Acoustic turn signal indicator (A1h2)
The messages shown on the multifunction display are split up according to their level of urgency into three categories: A symbol is displayed in the left multifunction display and the corresponding fault text is displayed in the right multifunction display.
- Category 1 (messages with highest priority):
Category 1 messages indicate security hazard conditions or situations, and they cannot be acknowledged by pressing the instrument illumination and reset button brightness control (A1r1). When they occur, a brief chime or a cyclical warning tone is heard. The message is displayed in the left multifunction display and any category 2 or 3 messages present are faded out.
- Category 2 (messages with medium priority):
Category 2 messages can be acknowledged. When they occur, a brief chime is heard.
- Category 3 (messages with low priority):
Category 3 messages can be acknowledged. When they occur a warning chime is not heard.
The messages can all be displayed in the Service menu.
The indicator/warning messages consist of the following subfunctions:
^ Function sequence for cruise-control control/warning messages
^ Function sequence for Distronic control/warning message (with code (219) Distronic (DTR))
^ Function sequence for Sensotronic Brake Control (SBC) control/warning messages
^ Function sequence for control/warning messages for supplemental restraint system
^ Function sequence, national seat belt reminder warning
^ Function sequence for warning messages for the exterior lights (ABL)
^ Function sequence for tire pressure loss warning (with code 477) Tire pressure loss warning)
^ Function sequence for tire pressure monitor warning messages (with code (470) Tire pressure monitor (standard) or code (475) Tire pressure monitor (premium))
^ Function sequence for emergency call system control/ warning messages (with code (359) TELE AID emergency call system)
^ Function sequence for memory adjustment control message
^ Function sequence for Keyless-Go control/warning messages (with code (889) Keyless Go)
^ Function sequence for audio/communication/navigation control messages
^ Function sequence for transmission-control control/ warning messages Function sequence for Active Body Control (ABC) control/ warning messages (with code (487) Active Body Control (ABC))
^ Function sequence for engine-control control/warning messages
^ Function sequence for Vario rood warning message
^ Function sequence, lights on reminder warning
^ Parking brake warning function sequence
^ Function sequence for speed warning (with code (623) Gulf States version)
^ Function sequence for engine oil level warning message
^ Function sequence for brake wear indicator warning message
^ Function sequence for brake fluid level warning message
^ Function sequence for coolant and coolant temperature warning message
^ Function sequence for windshield washer system fluid level warning message
^ Function sequence, turn signal confirmation
^ Function sequence for tank cap open warning message (with code (494) USA version)
Additional function requirements for cruise-control control/ warning messages
^ Engine running (circuit 61 ON)
^ Vehicle speed v > 30 km/h
The circuit 61 status is sent by the ME-SFI [ME] control unit (N3/10) to the engine compartment CAN (CAN C). The vehicle speed is calculated by the instrument cluster using the wheel speeds sent by the ESP, SPS [PML] and BAS control unit (N47-5) to the engine compartment CAN.
Function sequence for cruise-control control/warning messages
The cruise control regulates the vehicle speed to an adjustable value and it is activated using the CC [TPM] push button (S40) (without code (219) Distronic (DTR)) or the CC [TPM] push button (S40/4) (with code (219) Distronic (DTR)).
The cruise-control control/warning messages consist of the following subfunctions:
^ Function sequence for cruise control display
^ Function sequence for variable speed limiter display (without code (494) USA version)
^ Function sequence for permanent limiter display
Function sequence for cruise control display
When the cruise control is switched on, "CC [TPM]" is shown and the set speed in the left multifunction display. If the cruise control malfunctions, the ME-SFI [ME] control unit sends the corresponding data over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.
Function sequence for variable speed limiter display
The variable speed limiter governs the vehicle speed to a configurable value that lies between v = 30 km/h and the maximum speed. If the variable speed limiter is switched on, the configured speed is shown for t = 5 s in the left multifunction display (e.g. "Variable speed limiter 160 km/h"). The left multifunction display then returns to the display set by the driver. If the variable speed limiter malfunctions, the ME-SFI [ME] control unit sends the corresponding data over the engine compartment CAN to the instrument cluster.
The instrument cluster receives the data and then issues corresponding messages on the multifunction displays.
Function sequence for permanent limiter display
The vehicle's maximum speed can be permanently governed on the instrument cluster to a value between 160 km/h (e.g. for winter tire operation) and the maximum speed. This is shown on the left multifunction display just before the speed stored in the permanent limiter is reached.
If the permanent limiter malfunctions, the ME-SFI [ME] control unit sends the corresponding data 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 functional requirements for Distronic control/ warning messages (with code (219) Distronic (DTR))
^ Vehicle speed v > 30 km/h (calculated by instrument cluster)
Function sequence for Distronic control/warning messages (with code (219) Distronic (DTR))
Distronic regulates the vehicle's speed and automatically maintains the distance to a vehicle in front. All Distronic-relevant information is shown on the multifunction displays. If the Distronic function is activated, e.g. at v = 130 km/h using the CC [TPM] push button, the selected speed is then shown on the left multifunction display.
In the right multifunction display, the driver's own vehicle is shown on the right edge of the screen as well as a distance scale to the vehicle ahead.
The bar below the distance scale marks the target distance selected with the DTR distance potentiometer (N72r1). If Distronic recognizes through the DTR controller unit (A89) that the vehicle ahead is traveling at a slower speed, the ESP control unit sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the signals and actuates the DTR warning and indicator lamp (A1e59). A second vehicle is shown at the edge of the screen on the right multifunction display, which moves slowly over the distance scale. If the Distronic malfunctions, the ESP control unit sends the corresponding data 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 SBC control/warning messages
^ Circ. 15 ON
The status of circuit 15 is sent by the EIS [EZS] control unit (N73) to the interior CAN (CAN B).
Function sequence for SBC control/warning messages
If the Electronic Stability Program (ESP) is switched to passive, the ESP control unit sends corresponding information over the engine compartment CAN to the instrument cluster. The instrument cluster receives the data and actuates the ESP and ABS warning lamp (A1e41) permanently. The multifunction displays show "ESP", "ESP ON" or "ESP OFF". If the ESP control unit detects any faults or malfunctions in the SBC system, it sends the corresponding information in the same manner.
The instrument cluster receives the data and actuates the ABS indicator lamp (A1e17) and shows corresponding messages on the multifunction displays.
Additional function requirements for supplemental restraint system control/warning messages
^ Circuit 15 On (provided by EIS [EZS] control unit)
Function sequence for control/warning messages for supplemental restraint system
If there is a fault in the supplemental restraint system, the supplemental restraint system control unit (N2/7) sends corresponding data over the interior CAN to the instrument cluster. The instrument cluster receives the data and actuates the airbag indicator and warning lamp (A1e15) and issues corresponding messages on the multifunction displays.
If seat belts are not fitted, the instrument cluster activates the seat belt warning lamp (A1e9), depending on the national version it then flashes or stays on constantly.
Additional function requirements, national seat belt reminder warning
^ Engine running (circuit 61 ON)
^ Driver or front passenger seat belts not inserted
Function sequence, national seat belt reminder warning
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 evaluates the following information for issuing a country-specific seat belt reminder warning:
- For code (494) USA version
- Left front seat belt buckle restraint systems switch (S68/3)
- SRS right front seat belt buckle switch (S68/4)
- Front passenger seat occupancy status
- Without code (494) USA version:
- Left front seatbelt buckle microswitch (S68/9)
- Right front seatbelt buckle microswitch (S68/10)
A warning message for the front passenger is only issued, if the front passenger seat is recognized as occupied.
If a seat belt is not fitted, the restraint system control unit sends a corresponding signal over the interior 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.
- 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 (Euro NCAP): Europe (ECE), China and Australia.
In countries in which the seatbelt reminder is prescribed by law (extended NCAP), the seat belt warning lamp 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's seat belt is not fitted, the instrument cluster also issues an acoustic warning over the internal warning buzzer. To his end, the instrument cluster evaluates the status of the left front seat belt buckle restraint system switch or the left front seat belt buckle microswitch. The restraint system control unit routes this data over the interior 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. As soon as the engine running characteristics (circuit 61 ON) are detected then both the status of the left front seat belt buckle restraint system or the left front seat belt buckle microswitch, and the status of the right front seat belt buckle restraint system switch or the right front seat belt buckle microswitch is evaluated. 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 by flashing it at a frequency of f = 1 Hz. After all the acoustic warning phases have expired the seat belt warning lamp is permanently actuated.
- 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 expiry of 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.
- 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
- Ignition sequence as from circuit 61 ON detected again.