Service Surprise: E39 528i Alternator


Service Surprise: E39 528i Alternator

You could imagine that at a repair shop like Fluid MotorUnion we see vehicle problems ranging from the mundane to the really wild, as well as everything in between. With the wide range of vehicles we service and diagnosis, you can say on a typical day it would take a lot to surprise us. In this new blog segment called “Service Surprises” we will go over repairs that are unusual or catch us off guard by their rarity.

This customer came in with a 1998 BMW E39 528i with the M52 single vanos engine. His complaint was that the battery light was on, and he had to jump it to get it to the shop. A test of the charging system showed 12.6 volts, not close enough to the 14 volts needed to supply the vehicle. It was obvious after we performed a load test that the Alternator had died. While an alternator failure is not uncommon on the E39 chassis 5 series this one gave us a bit of a shock when we finally got it removed. The duct used to supply air to keep the alternator cool had become completely packed with leaves, dirt and rocks. While it is within the realm of possibility that this tube could become clogged, the crazy part was how long the alternator lasted like this. The tube didn’t become clogged like this overnight, no this was a result of years of driving. And with over 238000 miles on the clock it was inconceivable that this was the original alternator for the vehicle!

Needless to say, this customer got his money’s worth out of his original alternator!

Is your battery light on? Having a hard time starting your vehicle? You may need to have your charging system checked due to a failing alternator. So don’t wait and get stranded, call us at 815-230-2900, or contact us through email at We’re conveniently located in the Naperville/Plainfield area of the Chicago Metropolitan suburbs.


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