Electronic Ignition System Diagnosis (2.2L): Description

The Ignition Control (IC) module has independent power and ground circuits. The circuits between IC module and Powertrain Control Module (PCM) consist of the following:

• Low reference circuit.
• Low resolution engine speed signal.
• Two IC timing control signals for cylinders No. 1 and 4, and for cylinders No. 2 and 3.

IC module and PCM use low resolution engine speed signal to control ignition operation. Low resolution engine speed signal is derived from Crankshaft Position (CKP) sensor, which is connected directly to IC module.