The ignition coils put the spark into the air/fuel mixture so that it ignites inside the combustion chambers. The Powertrain Control Module (PCM) delivers a switched battery voltage and ground signal to the ignition coils, which are used to activate the spark and control ignition timing.
Multiple diagnostic systems use letters instead of numbers to refer to the location of a fault. In this case, the diagnostic code P2314 OBDII indicates a problem in the ignition coil secondary circuit voltage “E”, specifically it shows that there is a difference of at least 10% of the reference voltage, established by the manufacturer. For this reason, the Check Engine light will illuminate.