I went home to check voltage 1 more time and now have 17+.

I will check the VAC as recommended, but now I'm leaning back towards a failed regulator.

Yowza, 17+...hope my battery isn't cooked.

High DC voltages are usually due to failed rectifier diodes. As Diesel911 suggested, check for AC volts at the battery. If you have a failed rectifier diode, you will likely burn up another regulator.

__________________
Sam

84 300SD 350K+ miles ( Blue Belle )

Check your meter for accuracy also. A rough check is a new AA Alkaline battery should measure around 1.57 volts

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85 300D turbo pristine w 157k when purchased 167,870 July 2025
83 300 D turbo 297K runs great. SOLD!
83 240D 4 spd manual- parted out then junked

Replace the alternator.


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__________________
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