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Virginia Gentleman
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Agree with both posts above. I'd check and clean the battery posts and cables. If the no start condition and odd electrical conditions still exist (random dash lights) it points to a weak battery or insufficient charging system. As suggested, measure the voltage with the engine not running - should be a minimum of 12.8 volts and over 14 volts with the engine running. If it's less than 14 volts (engine idling) the alternator is bad (brushes worn or a bad diode).

Just went through this with my son's Mercury. Measured 12.4 volts at rest. Was getting intermittent no starts. With the engine at idle the voltage still only measured 12.4 volts so I knew the alternator was kaput - I'm guessing his had a bad or shorted out diode. Installed new alternator and the battery measured 12.6 volts at rest (just enough to start) and 14.5 volts initially and eventually dropped to a more normal 14.15 volts with the engine at idle.
 
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