The body control unit is an electronic control unit which is usually located behind the glovebox or near the centre console of the vehicle and is responsible for the monitoring and control of various electronic functions on the vehicle. These may include the immobiliser, the door locks, the electric windows and air conditioning of the vehicle as well as the power mirrors.
The body control unit is programmed specifically to each individual vehicle using a code to prevent theft. Whilst each body control unit is individually programmed, the way they work are generally the same. They consist of sensors, switches and programmed automatic reactions which work in unison in one computerised system to control vehicle functions.
If a body control unit fails, you may notice the intermittent or chronic failure of one or more of the electronic functions the module controls. Depending on which part of the vehicle fails this could be a very serious issue. For example, if the door locks fail you may have an issue opening your car to drive the vehicle. Any problems with the body control unit should therefore be rectified as soon as possible.