The ignition control module (ICM) is located on top of
the rear camshaft cover. The ICM performs the following several functions:
| • | Monitors the on-off pulses produced by the 2 crankshafts
and the camshaft position sensor. |
| • | Creates a 4X and 24X reference signal (4X ref high and 24X crank)
sent to the powertrain control module (PCM) for ignition control. |
| • | Creates a camshaft reference signal (1/2X cam high) sent to the
PCM for fuel injection control. |
| • | Provides a ground reference (ref. lo/cam lo) to the PCM. |
| • | Provides a means for the PCM to control spark advance (bypass
and ignition control), called ignition control mode. |
| • | Provides a limited means of controlling spark advance without
PCM input, called module mode. |
The ICM is not repairable. When a module is replaced, the remaining
components must be transferred to the new module.
