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Home >> Volvo >> 2004 >> XC70 >> Repair and Diagnosis (Single Page) >> External Pages >> Different car >> Section 9 (Alarm System, Control Modules, Engine Management Systems - Design And Function) >> Central Electronic Module (CEM) (2005-2007) >> Function >> Additional heater
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Additional heater

WARNING: This page does not describe the selected car, but rather 7 other vehicles, including the 2007 Volvo V70, 2006 Volvo V70, 2005 Volvo V70, 2004 Volvo V70, and 2003 Volvo V70. However, it is still accessible from the selected car via links, so may be relevant.
Fig 1: Additional Heater Communication Diagram
GLL146634Courtesy of VOLVO CARS OF NORTH AMERICA.

The additional heater is standard in cars with diesel engines (certain markets). This function is used for cars in cold markets to provide extra heat to the climate control module. The heater functions in the same way as the parking heater although the start conditions are different. This is controlled by the central electronic module (CEM) (4/56). There is no physical difference between the parking heater and the additional heater. The difference between the functions is in the software.