TSB = Technical Service Bulletin. Each one lists a known defect and probable cause. Normally issued when a number of similar failures occur with a particular model.

A TSB alerts the issuee of a problem that is perhaps a common failure with the model, but not widespread enough to warrant a recall.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car