Hi All,

What kind of AC ripple are you guys getting off this alternator?

I've got the AL129x alternator in both my 420SEL and 300SD.

I measured my 420SEL at the radio connector and found that there was about 425-460 mV of AC coming out of the alternator.

I've not had a chance to measure the 300SD.

I did measure my 300D which has the 150A alternator (cant remember the number on it). It has less than 70mV of AC ripple.

I am wondering if one of the diodes is going out on the AL129x. I'll have to put a scope on the output and see when I get a chance..

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