The Coil on plug ignition system is used in most engines today. It consists of an individual coil for each cylinder, which controls the Powertrain Control Module (PCM). With this system no spark plug cables are used, since the coil goes over the spark plug.
Each coil has two cables, one corresponding to a battery power supply, then where the energy is usually distributed. The other cable is the coil exciter circuit of the Power Train Control Module (PCM).
The Powertrain Control Module disconnects the circuit or grounds, in order to activate or deactivate the coil can ground or disconnect the circuit and thus enable or disable the coil. The circuit of the coil driver is continuously supervised by the Power Train Control Module for future problems. If a short is sensed in the exciter circuit of coil 2, the diagnostic code P0352 OBD2 is set.