Coil On Plug (COP)
The COP is part of the distributorless ignition system. The COP eliminates the need for secondary spark plug wires which improves reliability. The COP is the source of the high voltage which is used to generate the spark by the spark plug. There is 1 COP for each cylinder. The COP is mounted directly to the spark plugs. The function of the COP is to convert low voltage into high voltage in excess of 40, 000 volts.
The COP consists of primary and secondary windings. The primary winding is energized by the VPWR circuit. The PCM coil driver circuit is connected to the primary winding as well. The secondary winding is connected to the spark plug. The current flowing through the primary winding generates the magnetic field across both windings. The PCM activates the coil driver circuit by opening it. The instant the circuit opens the magnetic field collapses, inducing current flow in the secondary winding.
The COP has three different modes of operation: engine crank, engine running, and CMP failure mode effects management (FMEM).