GF54.30-P-3041TX Display Operating Conditions, Function

GF54.30-P-3041TX Display Operating Conditions, Function

Component Identification:

Function requirements for all displays:
^ Circuit 15 ON

Detect and display fuel supply
The fuel supply is displayed to the driver by the fuel level and reserve indicator (A1p2) and if necessary by the fuel reserve warning lamp (A1e4)

The information transmitted to the rear SAM control unit by the fuel level sensors is read by the instrument cluster over Controller Area Network bus class B (interior) (CAN-B).
Refueling is only detected (display updated) when a refill quantity of at least 9 l has been added.

There is always a delay before the display is updated. This reduces display fluctuations. The reserve range corresponds to a fuel quantity of between 0 and approx. 9 liters. When the reserve range is reached, the fuel reserve indicator lamp lights up yellow if the engine is running. The lamp is triggered with a delay period to prevent the lamp flickering.

In the event of a fault, the needle of the fuel level and reserve indicator moved to "0." The fuel reserve indicator lamp is not actuated.

Detect and display outside temperature
The outside temperature display located in the right-side multifunction display (A1p13) indicates temperature based on the following information:
^ The outside temperature reading
^ The vehicle speed signal
^ The coolant temperature
^ The engine running time

The instrument cluster processes this data and actuates the outside temperature indicator accordingly. The dependency of the outside temperature indicator on the speed, the engine running time and the coolant temperature prevents too high a temperature being displayed when the vehicle is stationary or moving slowly.

The display's response pattern varies according to coolant temperature and engine running time:
^ The coolant temperature is < 60 °C. When the instrument cluster is activated, the current outside temperature is always displayed.
^ The coolant temperature is ≥60 °C. At "circuit 15C" the last measured temperature is stored and then displayed for a maximum of 60 minutes. When the instrument cluster is activated, the stored temperature is always displayed.

Detect and display speed
All wheel speeds are evaluated by the instrument cluster to calculate the speed. The signals from the following sensors are registered:
^ Left front rpm sensor
^ Right front rpm sensor
^ Left rear rpm sensor
^ Right rear rpm sensor

The instrument cluster receives the wheel speeds in rpm from the ESP control unit via the Controller Area Network bus class C (engine compartment) CAN-C. The electronic speedometer (A1p8) with its speedometer arc displays the vehicle speed
The speedometer arc is not displayed if a speed limit (adjustable in multiples of 10 km/h from 160 km/h to 210 km/h or in multiples of 10 mph from 100 mph to 150 mph) is activated via the 2nd control level of the instrument cluster.

The vehicle speed is shown in digital form on the multifunction display. The basic setting for the display unit is stored on a country-specific basis in a non-volatile memory and can be changed in the menu item "Settings". The digital speed display is matched to the speedometer display by a performance ma
This ensures that the value of the analog needle position and the reading shown on the display match.

No speed display appears if error messages are received for all wheel speeds. As the distance readings are also based on monitored speed, the odometer will cease to operate.

The tire size is taken into account when calculating the speed. Coding takes place using STAR DIAGNOSIS.

Detect and display coolant temperature
The resistance of the coolant temperature sensor is read by the ME-SFI [ME] control unit and placed on the CAN-C. The instrument cluster reads this value from the CAN-C and actuates the coolant temperature display accordingly. A warning message appears in the multifunction display if necessary.
The coolant temperature display is a segmented display. When the instrument cluster is activated, one segment is actuated at temperatures < 40 °C; at higher temperatures the segments are actuated according to the values measured by the coolant temperature sensor. The display is held at 95 °C for input values from 95 °C to 115 °C.

If the engine and AC electric suction fan with integrated control (M4/7) is faulty, the characteristic is abandoned and values between 96 °C and 116 °C are displayed.

Detect and display engine speed
The engine speed is recorded by the crankshaft position sensor (L5) (engine 113) or by the crankshaft Hall sensor (engine 272, 642). The signals are read by the ME-SFI [ME] control unit (engine 113, 272) or by the CDI control unit (N3/9) (engine 642) and placed on the CAN-C in rpm. The instrument cluster receives this signal and actuates the stepper motor for the tachometer relative to the engine speed.

If the signals are implausible, the tachometer needle is moved to the left-hand side of the scale. An error bit is also stored in the fault memory.

Detect and display mileage
The total mileage and trip mileage are determined from the speed and tire size.
The total mileage is displayed on the 6-digit display in the standard display below the multifunction display in kilometers or miles as soon as the instrument cluster is activated.
The range for the main odometer is from 0 to 999,999 kilometers or miles. If the maximum mileage is reached, the counter is not reset to 0. In this case, the instrument cluster should be replaced. However, the internal counter continues to operate up to a maximum of 1,677,721 km or 1.000.000 miles. Processing always takes place in kilometers, the display in miles is converted. The main odometer reading is stored for at least 5 years, even if the voltage supply is disconnected. Functional integrity is guaranteed under normal conditions over the full service life of the vehicle (15 years or 10,000 operating hours).

The trip mileage is displayed as a 5-digit number on the basic display of the multifunction display in kilometers or miles as soon as the instrument cluster is activated. The range for the trip mileage odometer is from 0 to 9999.9 kilometers or miles. Once the maximum reading is reached the display is reset to 0. The trip odometer is reset to 0 by holding down the instrument illumination rheostat and reset button (A1r1) for t > 2 s.

If all wheel speed signal values are implausible, the values on the main and trip odometer "freeze" and an error bit is stored in the memory.

The total distance remains stored for at least 10 a when the battery is disconnected (G1). The trip mileage is also protected against data loss if the battery is removed for a short period of time.

Display transmission information
The highest shift range selection which the automatic transmission (AT) can upshift to is shown on the gear indicator display (A1p12). On vehicles with additional manual mode, the actual engaged gear is shown on the display when this mode is selected on the transmission mode switch (S16/5).
The setting of the transmission mode switch is shown on the transmission mode display (A1p16) on all vehicles.

Display and set clock
The time is displayed in analog form via hour and minute hands on the electronic clock (A1p6). The minute pointer is moved in steps of 1 minute. The hours pointer is coupled to the minute pointer by a mechanical gear ratio.
On vehicles with Audio 20, the electronic clock is set via the menu "Settings". On vehicles with COMAND operating, display and control unit (A40/3) or with radio control panel and navigation unit (A2/56), the time information is placed on to the CAN-B by these control units and read by the instrument cluster.