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Ignition Amplifiers / Coils



Ignition Amplifiers / Coils

Description

The ignition amplifiers monitor is very similar in operation to the injectors monitor, albeit checking primary coil current instead of voltage.

Internal hardware detection circuits in the ECM, monitor the individual and group outputs to the coil primaries for incorrect current conditions. If a failure is repeatedly noted over a predefined number of engine revolutions then a failure of the appropriate coil or group circuit is registered. If the failure is registered on 2 drive cycles then the MIL will illuminate.