Failure Effects Mode Management (Fail Safe Operation)
PURPOSEDuring some Electronic Ignition System (EI) failures, the Failure Mode Effects Management (FMEM) portion of the Ignition Control Module (ICM) will maintain vehicle operation.
OPERATION
If the ICM does not receive the Spark Output (SPOUT) signal, it will turn the coils on and off using the Profile Ignition Pick-up (PIP)signal. In doing so, the timing and dwell are fixed at 10 degrees BTDC.
If the ICM does not receive the Cylinder Identification (CID) input signal, random coil synchronization will be attempted. Several start attempts may be required before the engine will start.
If the ICM loses CID input while the engine is running, the module will remember the proper firing order and continue to fire in order to maintain engine operation.