Ignition Control Module: Description and Operation

Dual Plug DIS Module:

The main function of the Distributorless Ignition System (DIS) module is to switch between ignition coils and cause these coils to spark. The module receives the Profile Ignition Pick-up (PIP) signal from the crankshaft sensor, the Cylinder Identification (CID) signal from the camshaft sensor, and the Spark Output (SPOUT) signal from the Electronic Control Assembly (ECA). During normal operation, PIP is sent to the ECA to provide base timing and engine rpm information. The CID signal provides the DIS ignition module with the information required to synchronize the ignition coils so that they are fired in the proper order. The SPOUT signal contains the optimum spark timing and dwell information. The spark angle is determined by the rising edge of the SPOUT signal. The falling edge controls the ON or dwell time of the coil current. The dwell time is controlled by varying the duty cycle of the SPOUT signal. With the proper inputs from PIP, CID, and SPOUT the DIS module turns the coils ON and OFF in the proper order for spark control.