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Seat Heating



Seat Heating

Seat heating
Seat heating is offered in the E70 as an optional extra. The seat heating is operated electrically. Seat heating serves to set up a pleasant temperature in the seats. The seat heating is offered in two equipment variations (Low and High).

Brief description of components
The following components are described for the seat heating:
- Integrated automatic heating and air conditioning system (IHKA)
- Junction box electronics (JBE)
- Heating element

Integrated automatic heating and air conditioning system (IHKA)
The seat heating is activated using the outer buttons of the IHKA. The IHKA processes each button signal. An indicator light lights up in the button for each selected temperature setting. The IHKA sends a message via the K-CAN to the junction box electronics (JBE).

Junction box electronics (JBE)
The JBE handles the electrical power supply for the seat heating. The heating elements in the driver's seat are activated via the driver seat module (SMFA). In the equipment specification "Low", the JBE activates the heating elements on the passenger's side. Depending on the selected temperature setting, the JBE generates a pulse modulated signal that activates the heating elements on the passenger's side. In the equipment specification "High", the passenger seat module (SMBF) activates the heating elements.

Heating element
The seat heating consists of a number of heating elements. The heating element consists of flexible electrical wires. The heating elements are integrated into the seat and backrest cover of the driver's and front passenger's seat. The heating element runs through the entire cover of the seat cushion and the backrest.












System functions
The following system functions are described for the seat heating:
- Heat up seat heating
- Monitor seat heating
- Cool down or switch off seat heating

Heat up seat heating
Pressing the relevant button on the IHKA activates the corresponding seat heating. Pressing the button again changes the heat output of the seat heating. The set temperature setting is indicated by the indicator lamps in each button.

Monitor seat heating
The seat heating is monitored by a temperature sensor (NTC hot conductor). The temperature sensor is located in the heating element of the seat heating. The temperature sensor monitors the temperature and protects against overheating.

Cool down or switch off seat heating
The seat heating is switched off by pressing the relevant button until no indicator light is lit up. The seat heating can also be switched off by pressing the relevant button for a longer period.
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