Check your running voltage with a meter at the battery, if you are eating bulbs you could have high voltage. Should be in the high 13's or very low 14s on dc, if higher the regulator is bad. Then try reading ac across the battery while running, should be less than a few hundred millivolts, otherwise it's bad diodes in the alternator.

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The OM 642/722.9 powered family
Still going strong
2014 ML350 Bluetec (wife's DD)
2013 E350 Bluetec (my DD)

both my kids cars went to junkyard in 2023
2008 ML320 CDI (Older son’s DD) fatal transmission failure, water soaked/fried rear SAM, numerous other issues, just too far gone to save (165k miles)
2008 E320 Bluetec (Younger son's DD) injector failed open and diluted oil with diesel, spun main bearings (240k miles)

1998 E300DT sold to TimFreeh
1987 300TD sold to vstech