On my 1979 240D, the alternator light comes on while idling. When I start to drive down the road it goes off, but when I slow down or stop at an intersection, it comes on very dimly. This always repeats itself. I have never had any trouble (yet) with the car starting. I imagine it could be a voltage regulator problem, but my question, is with multimeter in hand, how do I check the alternator output? bear in mind, I havent used a voltmeter very often except to test continuity in circuits, so be specific with instructions!

thanks,
Jim
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1979 Mercedes 240D (Sold to a neighbor last year,now I have room for a new one,looking for a 300D this time)
1980 Mercedes 240D(bought for a parts car, but I have fun driving it!

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