carfobbattery

Audi A8 key fob battery

13 of the 28 model years listed for the Audi A8 have a proven battery. The most common answer is CR2032. Rows below run oldest to newest; a year can appear twice when the car came with more than one kind of key.

  1. 1997-2001Key-head remote

    CR2032

    FCC ID MYT8Z0837231

    Two sites agree: uhs-hardware.com and americankeysupply.com (checked Nov 1, 2026)

    Find CR2032 on Amazon
  2. 2002-2005Unknown

    Not confirmed yet

  3. 2006-2010Key-head remote

    Not confirmed yet

  4. 2009-2016Smart key

    CR2032

    FCC ID IYZFBSB802

    Two sites agree: uhs-hardware.com and bestkeysupply.com (checked Nov 1, 2026)

    Find CR2032 on Amazon
  5. 2017-2024Unknown

    Not confirmed yet

Changing the battery

Key with remote in the head

  1. Here the key blade and remote are one piece. You open the plastic head, not the blade.
  2. Work a thin flat tool into the seam near the blade and twist; go round slowly if it does not open at once.
  3. The coin cell is usually under or on the back of a small board. Keep the rubber button pad in place while you swap the cell.
  4. Snap it closed and press each button. The car still starts with a dead remote battery on most of these keys, because the start chip needs no battery.

A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

Smart key (push-button start)

  1. Most push-button fobs hide a metal backup key. Press or slide its catch and draw the key out first.
  2. Use the slot where the metal key sat. Twist, do not lever hard, and work along the seam until the halves separate.
  3. Pop the old battery out with a toothpick or plastic pick, not a metal blade, and seat the new one with the + side matching the old one.
  4. Snap the halves back together, slide the metal key home, and press each button, then try the start button from the driver's seat.

A CR2032 is 20 mm across and 3.2 mm thick. CR2032, CR2025 and CR2016 share the same width but not the same thickness, so a swap between them can leave a loose contact or a case that will not close.

Keep spare coin cells away from small children. A swallowed coin cell can burn the throat within hours; if it happens, go to an emergency room at once.

Other Audi models