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Ignition Coil

Fig 38 Ignition Coil:






The Automatic Shutdown (ASD) relay provides battery voltage to the ignition coil.
- The PCM provides a ground contact (circuit) for energizing the coil.
- When the PCM breaks the contact, the energy in the coil primary transfers to the secondary causing the spark.
- The PCM will de-energize the ASD relay if it does not receive the crankshaft position sensor and camshaft position sensor inputs. Refer to Automatic Shutdown (ASD) Relay operation for more information.