Outside Temperature Display

Outside Temperature Display

The instrument cluster determines the current outside temperature by way of the outside temperature sensor (NTC resistor). The outside temperature sensor is connected with a separate ground (analog ground) and a sensor line (analog positive) to the instrument cluster. The outside temperature is displayed permanently in the instrument cluster. If, while driving, the outside temperature drops below +3 degree C, dependent on the coding, a warning tone (gong or peep tone for ice warning dependent on coding) is triggered and the displayed value flashes.

The display unit (degree C/degree F) is determined in the coding data. However, it is possible (from diagnosis index 31, refer to "diagnosis program", ", "instrument cluster", ", "identification") to change the display unit from degree C to degree F and from degree F to degree C. For this purpose, the ignition lock must be switched from position "1" (terminal "R") to position "0" (terminal "15" and terminal "R" OFF) with the trip odometer reset button pressed. The displayed temperature unit is changed after releasing the trip odometer reset button and from ignition lock position "1" (terminal "R"). The set unit display is retained for as long as supply voltage is applied to the instrument cluster and no reset is triggered.

The display range extends from -40 degree C to +50 degree C. An increasing outside temperature display is delayed, since heat from the engine and other ambient conditions influence the outside temperature display. A drop in the outside temperature is not delayed.

The instrument cluster transfers the "outside temperature" information via the body bus (K-Bus ). In ignition lock position "0", the outside temperature sensor is read by the instrument cluster at time intervals which are within the minute range. For this purpose, the instrument cluster is temporarily activated, provides the information and then switches itself off again.