Ignition Control Module Replacement for Cadillac DeVille 1996
Ignition Control Module Replacement L47
The ignition control module (ICM) is located on top of the
rear camshaft cover. The ICM performs sever functions:
| • | It monitors the ON-OFF pulses produced by the tow crankshaft and
the camshaft position sensor. |
| • | It crates a 4X and 24X reference signal (4X ref. hi and 24X crank)
sent to the PCM for ignition control. |
| • | It creates a camshaft reference signal (1/2X cam hi) sent to the
PCM for fuel injection control. |
| • | It provides a ground reference (ref. lo/cam lo) to the PCM. |
| • | It provides a means for the PCM to control spark advance (bypass
and ignition control), called ignition control mode. |
| • | It 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. Refer to Ignition Control Module Replacement (Assembly)
.
