Be sure to check the wiring that goes to the alternator as well. I had lot's of trouble with my 240D's alternator. I changed the regulator which help for a while but then found that the wires going to the alternator were frayed so badly that some of them were not even making contact. In the end though I also had to replace the alternator.

- Peter.

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2021 Chevrolet Spark
Formerly...
2000 GMC Sonoma
1981 240D 4spd stick. 347000 miles. Deceased Feb 14 2021
2002 Kia Rio. Worst crap on four wheels
1981 240D 4spd stick. 389000 miles.
1984 123 200
1979 116 280S
1972 Cadillac Sedan DeVille
1971 108 280S