Displaying Check/Warning Messages Via Multifunction Display

Displaying Check/Warning Messages Via Multifunction Display, Function

Left and right multifunction displays (A1p13 and A1p15)
The left and right multifunction displays (A1p13 and A1p15) provide the driver with various items of information, which can be selected using the buttons on the multifunction steering wheel. In addition to the familiar displays of odometer and trip counter readings in the left multifunction display (A1p13) and the outside temperature in the right multifunction display (A1p15) (main screens), further systems can also be displayed using the system select pushbuttons (S110s3):
- Audio display
- Navigation (option)
- Distronic (option)
- Fault and warning messages
- Vehicle configuration
- Trip computer
- Telematics/Tele Aid (USA) (option)
- Telephone display (option)
- TV tuner (option)

Furthermore, fault and warning messages appear in the left and right multifunction displays (A1p13 and A1p15) if malfunctions occur.

Classification of fault messages and warnings in categories
The messages are divided into three categories according to their priority.
- Messages of the highest priority belong to category 1. These messages cannot be acknowledged. A short warning chime also sounds when these messages are displayed. Any faults of categories 2 and 3 are hidden.
- Messages of medium priority belong to category 2. These messages can be acknowledged using the instrument illumination dimmer and reset button (A1 r1). A short warning chime also sounds when these messages are displayed. Any faults of category 3 are hidden.
- Messages of the lowest priority belong to category 3. These messages can be acknowledged using the instrument illumination dimmer and reset button (A1 r1). There is no warning chime.

NOTE: A symbol identifying the faulty system is displayed in the left multifunction display (A1p13), while an explanation or instructions on how to respond to the problem appears in the right multifunction display (A1p15).

Fault storage
The messages are stored in 3 roller memories according to their priority:

U-roll
This is the list of all unacknowledged warning messages displayed in the left multifunction display (A1p13). Displays of equal or higher primary priority are shown after the minimum display time of the preceding message has elapsed. When the minimum display time for the warning with the lowest secondary priority has elapsed, the fault roll begins again with the warnings with the highest secondary priority (ring memory).

NOTE: All warnings in the U-roll are displayed at increased brightness.

W-roll
All faults occurring and acknowledged while driving are recorded here. It can be called up at any time in the menu tree in the left multifunction display (A1p13).
When the roll is called up, a start screen appears first displaying the number of faults that have occurred; then the faults are displayed in the order or their primary priorities.

N-roll
In this roll all the messages recorded in the fault roll are automatically called up in the order of their secondary priorities when terminal 15R is switched off.
The start screen displays the number of faults recorded. The warning buzzer (A1h1) is actuated briefly when the start screen is displayed.
The displayed messages must be acknowledged. The N-roll is closed when all the warnings have been acknowledged.

If there are no messages recorded, or if all the recorded messages have been acknowledged, the left multifunction display (A1p13) is switched off after 30 s. If there are still unacknowledged message present, the display waits 2 minutes before shutting down. If the N-roll is interrupted by a higher-priority message, it begins again from the start screen.

Acknowledging messages
Warning and fault messages can be acknowledged manually or automatically. To acknowledge manually, press the
- scroll forward/back pushbutton (S110s1)
- system select pushbutton (S110s3) or
- instrument illumination dimmer and reset button (A1r1)
If the cause of an automatically acknowledgeable message ceases to be applicable, the warning is displayed for the duration of its minimum display time in the left multifunction display (A1p13).

If there are no other faults, the display changes to the previous display screen after acknowledging a fault message.

NOTE:
- Some messages are accompanied by the lighting of a warning or indicator lamp. These lamps remain lit until the fault is rectified. This applies even if the corresponding message was acknowledged.
- A maximum of 16 messages can be stored. If another fault occurs, the oldest message is overwritten.

Display of warning and fault messages
With very few exceptions (e.g. lights warning, key in ignition), fault messages are only displayed when the engine is running.
- Current messages
Current messages are displayed immediately. If the fault occurs for just a short time, messages of categories 2 and 3 are displayed for at least 2 seconds. Messages of category 1 are displayed for as long as the fault is present.
- Several current messages
- If several faults of different priorities are present at the same time, the message with the highest priority is displayed.
New messages with equal or higher priority hide the previously displayed message.
- If several faults of the same category are present, the display cycles through each of the messages every 2 seconds.

Displaying stored fault messages
When the instrument cluster (A1) is active, it is possible to scroll through the stored error messages:
- Press the system select pushbutton (S110s3) repeatedly until the "- FAULTS" display appears in the left multifunction display (A1p13).
- Scroll through the fault messages using the scroll forward/back button (S110s1). The messages are displayed in the order of their priorities.

Example
Four of the approximately 200 possible messages can be found below accompanied by a short description.

The sequence of the displayed messages if there are several faults is discussed using an example:
- The washer fluid level has fallen below the minimum mark. The symbol for the faulty system appears in the left multifunction display (A1p13) and the category 3 message "CHECK WASHER FLUID LEVEL" appears in the right multifunction display (A1p15) (Figure 1).
- If a fault now occurs in the alternator (G2), the category 2 message "BATTERY/ALTERNATOR VISIT WORKSHOP!" is displayed (Figure 2). This message hides the first message because it has a higher priority.
- If the engine coolant level now falls below the minimum mark, the category 2 message "CHECK COOLANT LEVEL!" is displayed (Figure 3).
The display now alternates every 2 seconds between this message and the message "BATTERY/ALTERNATOR VISIT WORKSHOP!" (Figure 2) because there are now two messages with the same priority.

In this example, it is assumed that no message has been acknowledged.

- Message: "CHECK WASHER FLUID LEVEL!"

Figure 1:

This category 3 message is displayed when the level of washer fluid for the windshield and headlamp cleaning system drops below the minimum. This information is transmitted over the interior compartment CAN from the passenger-side SAM control module (N10/11). For further details, refer to "Voltage coding of coolant/windshield washer fluid level, function".

- Message: "BATTERY/ALTERNATOR VISIT WORKSHOP!"

Figure 2:

This category 2 message is displayed if the alternator (G2) is not working correctly, but the engine speed is higher than 200 rpm. For further details, refer to "Battery charge and alternator check, function"

- Message: "CHECK COOLANT LEVEL!"

Figure 3:

This category 2 message appears when the coolant drops below the minimum level. This information is transmitted over the interior compartment CAN from the driver-side SAM control module (N10/10). For further details, refer to "Voltage coding of coolant/windshield washer fluid level, function".

- Message: "VISIT WORKSHOP/DISPLAY FAULTY!"

Figure 4:

This category 2 message appears when there is a fault in the interior compartment CAN and/or the engine compartment CAN, which affects communications with several control modules. If the link to only one control module is affected, the symbol for the affected system appears at position (2) in Figure 4.