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Home >> Volvo >> 2003 >> XC70 >> Repair and Diagnosis >> External Pages >> Different car >> Section 9 (Alarm System, Control Modules, Engine Management Systems - Design And Function) >> Climate Control Module (2001-2004) >> Function >> Seat heaters
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Seat heaters

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: Seat Heaters Input And Output Signals
GLL107518Courtesy of VOLVO CARS OF NORTH AMERICA.

The seat heaters are activated by pressing the switches on the climate control module (CCM) (3/112). The climate control module (CCM) transmits information via the Controller area network (CAN) about the status selected for each seat to the central electronic module (CEM) (4/56). The central electronic module (CEM) then transmits the information to the relevant control module for seat heating (4/201, 4/202). The control modules for the seat heaters then control the current to the heater pad for the left-hand seat (9/16, 9/18) and right-hand seat (9/17, 9/19).

The central electronic module (CEM) also transmits information to the climate control module (CCM) about whether the seat heaters are activated or not. The climate control module (CCM) uses this information to light / turn off the LEDs on the buttons.