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How do you change the battery on your Audi key fob?

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July 19, 2012 4:34PM

The question is understandable. Anyone who owns an Audi knows these are expensive, to very expensive, keys to replace depending on whether you buy online or go to an Audi dealer. You would not want to break one.Case separation is easy by simply placing the tip of a flat screwdriver or butter knife in the indent on the side that has the Audi symbol and turning it to apply pressure pushing the two halves apart. One half is the mechanical switchblade key and the other, with the buttons, is the electronic half.

The electronic side with the FCC and ID numbers on it does pry open. The entire top will come off, not just the small square with the writing on it and the Figure 8 key ring will fall loose. Remember to put it back when clicking the case back together.

My key is for an 2001 A8 but all may be the same . The batteries (2) are CR1620 and both are inserted positive side down. Once the case is clicked together simply slide the mechanical and electronic halves back together. If the locks don't immediately respond to the remote, insert the key in the drivers door and lock the car, then try opening it with the remote.


The key fobs are obviously different for different models. My key is for a 2007 Allroad and it is a key fob for an advanced key system (doors open when you approach the car with the key in your pocket).

You need one CR2032 button cell battery (between £0.30 and £3.00, so check where you get it from).

The lid you need to open is on the side with the Audi logo on it. It is secured in 3 places. Unfold your key first (push the silver button).In the area where the key is usually folded into, you can see a small gap. Push gently with a screw driver into that gap, pushing against the lid that you want push open. It should come up slightly. Use the key ring holder as a lever pushing the screw driver top through the key ring holder and under the lid you want to open. You should now be able to lift the lid without any problems. Make sure you put the battery in the right way round, which is with the writing on top


For a 2009 A4 with keyless ignition, the battery is one (1) CR2032. To replace it, remove the emergency backup key by pressing the button on the reverse side (no Audi logo) of the silver part and slide the key straight out. Turn unit over and press the black button located on the opposite side of the silver button you used to remove the emergency backup key, while pulling straight out to reveal the battery tray. This takes a little more effort as there is a rubber grommet on the battery tray which provides friction. Replace battery (positive side up, large flange side down) and reassemble. The procedure is also in the owner's manual.


I have 2001 Audi tt. Everything said in the first message is correct for this car and the batteries are 1620.

I have a 2002 Audi TT. The above is true except for the fact that my fob did not start responding until I put the key in ignition and at least turned on the battery. I think it might have something to do with re-registration of the fob inside of the car.

I have a 2001 Audi A4 and the 1st message is correct. 2 x CR1620 batteries.

I have a 1998 Audi A4. Everything said in the first message is also correct for this car, batteries are 1620.

I have a 2000 s4. Everything said is also correct for mine two 1620's. br /> ----------


I have a 2000 Audi A4. In order to get the fob to work again, you must insert the key in the drivers door and lock the car (while pushing down on the lock button), then try opening it with the remote. That will then reprogram the fob

We have 2007 Audi A4. Everything said in the first message is correct for this car except in order to get the fob to work again, you must use the key to start the car. That will then reprogram the fob.