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Electronic Ignition (EI) System Diagnosis



Electronic Ignition (EI) System Diagnosis

Circuit Description

Each ignition coil/module has the following circuits:

* An ignition voltage circuit
* A ground
* An ignition control (IC) circuit
* A low reference circuit

The powertrain control module (PCM) controls the individual coils by transmitting timing pulses on the IC circuit of each ignition coil/module to enable a spark event.

The spark plugs are connected to each coil by a short boot. The boot contains a spring that conducts the spark energy from the coil to the spark plug. The spark plug electrode is tipped with platinum for long wear and higher efficiency.

Diagnostic Aids

Perform the spark plug inspection procedure before continuing with this diagnostic. Refer to Spark Plug Inspection. Testing and Inspection

Test

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Step 11 - Step 14:




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