is it possible to have a malfunctioning alternater on this car without the warning light coming on?ive been caught with a dead battery twice in the last several days despite a battery change.car starts fine then dies after a 1/2 hr or so of driving.very inconvenient.any suggestions for a fast easy alternater check

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michael cole 1980 300SD gone now but not forgotten,87tdt,90 300te 4matic 95 e320 wagon

mike,take voltmeter and check battery with car running and if alt bad you will find volts less than 12. if good the volts will be about 13 or higher. david poole dallas tx.

thanks david i will check the output.should the alternator normally output enough current to keep the ignition going without accessories even if the battery is dead?

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michael cole 1980 300SD gone now but not forgotten,87tdt,90 300te 4matic 95 e320 wagon