Since 5/97 an instrument cluster has been phased-in which features the plugged-on instrument cluster electronics (IKE ) integrated in the display unit (AE ). This instrument cluster can replace older instrument cluster versions.
The instrument cluster determines the current coolant temperature by way of the coolant temperature sensor (NTC resistor). The coolant temperature sensor is connected with a separate ground (analog ground) and a sensor line (analog positive) to the instrument cluster electronics (IKE ).
In the case of the integrated version of the instrument cluster, phased-in as from 5/97, the coding data defines whether the coolant temperature signal is routed via the CAN bus from the engine control unit or via a separate line from the coolant temperature sensor to the instrument cluster.
The instrument cluster electronics (IKE ) transfers the "coolant temperature" information via the instrument bus (I-bus ) and body bus (K-bus ).