Ignition Control (IC)

Ignition Control (IC)
This system uses similar circuits between the 1CM and the PCM that a distributor type system uses. Following is a brief description of the IC circuit.
Ignition control A & B The PCM sends the Ignition Control (IC) pulses to the ICM on these circuits. These signals are similar to the 7x reference pules square wave except that the PCM uses the sensors inputs to determine the pules timing to control spark advance.
When the PCM receives the 7x reference signal, the PCM will determine which pair of cylinders will be fired (1 & 4 or 2 & 3).