At a glance
What can fail
Sulfur in gasoline reacts with certain fuel additives and deposits on the contact points of three fuel sending units inside the tank, causing the fuel gauge to read full when the tank may actually be partially full or empty.
What the fix does
Dealers replace the fuel sending units with new units using a gold, silver, and nickel alloy that resists sulfur buildup.
Summarized — see the official notice for exact wording, dates, and contacts.