Intrigue V6-3.8L VIN K (1998)
Ignition Control Module: Description and Operation
The ignition control module performs the following functions:
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It powers the dual crankshaft position sensor internal circuits.
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It supplies the voltage signals that each respective Hall effect switch pulses to ground to generate the CKP Sync and CKP 18X signal pulses.
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It determines the correct ignition coil firing sequence, based on how many CKP 18X signal transitions occur during a CKP Sync pulse. This
coil sequencing occurs at start-up. After the engine is running, the module remembers the sequence, and continues triggering the ignition coils
in proper sequence. If the CKP Sync pulses are missing at start-up, the ignition control module will be unable to determine the proper ignition
coil sequence and a loss of spark will occur. However, normal fuel injector pulses will occur
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It determines whether or not the crankshaft is rotating in the proper direction, and cuts off fuel delivery and spark to prevent backfiring and
reverse rotation is detected.
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The ignition control module sends the 3X reference and 18X reference signals to the PCM. The PCM determines crankshaft position and
engine RPM from these signals. The PCM uses these signals for Ignition Control (IC) spark timing calculations. The falling edge of each 3X
and 18X reference pulse occurs at a specific time in relation to top dead center of any cylinder stroke. The 3X reference signal is an ON - OFF
pulse occurring 3 times per crankshaft revolution. The 3X reference signal is not the CKP Sync pulse. To produce the 3X reference signal the
ignition control module receives the 18X CKP signal, and processes the signal through as internal divide-by-6 circuitry. If the 18X CKP signal
is missing at start-up, the ignition control module will be unable to generate the 18X or 3X reference signals, and a loss of spark and fuel
injection will occur.
