Audi Key Fob Battery Replacement: A Step-by-Step Guide
If your Audi key fob’s range has diminished, or it only works intermittently to lock/unlock doors, it could indicate a depleted battery that needs replacement. This is a common service requested by Audi owners once the key fob batteries reach the end of their lifespan. While an Audi dealership or mechanic shop can replace key fob batteries for you, oftentimes the repair is relatively quick and affordable to do on your own at home.
When You Should Replace Your Audi Key Fob Battery
Signs It’s Time
- Reduced range – The maximum distance you can be from the vehicle and still use the key functions is shortened. Most key fobs have a range of at least 50-100 feet when new.
- Intermittent issues – Doors fail to lock or unlock every time you press the key fob buttons, requiring multiple tries. You may have to be standing closer to the vehicle to get a response.
- Warning light – Some Audi vehicles will display a warning icon or signal on the dashboard if the key fob battery is low. This notification often appears months before total key fob failure.
Risks of Waiting Too Long
Putting off battery replacement once you notice any issues with key fob operation or receive a low battery warning light risks complete key fob failure at the most inconvenient time. You could be unable to unlock and start your car until you replace the battery. It also forces you to physically stand closer to the vehicle to use the key fob in its diminished state for locks.
Audi key fob batteries are usually designed to last 1-2 years, depending on the level of use and temperature conditions. The optimal practice is to change the battery once a year as preventative maintenance if warning signs haven’t appeared yet. Cold weather tends to accelerate battery drain. Pay attention to the fob function during winter months.
Overall, address any indications of Audi key fob battery problems promptly before you experience complete failure and can’t unlock or turn on your vehicle.
Preparing for Audi Key Fob Battery Replacement
Performing a DIY battery swap with a new CR2032 only requires a few basic items and about 10-15 minutes to complete.
You’ll need:
- A correct replacement CR2032 coin cell battery – Match OEM specs exactly. It powers all key fob functions.
- A small Phillips screwdriver to open the key fob casing.
- A clean cloth and safety glasses for your work surface, hands, and eyes.
- Enough light and free space to see clearly inside key fob and complete repairs.
Precautions to prevent damage:
- Avoid touching the battery contacts inside the key fob during replacement. Skin contact will quickly corrode the metal over time.
- Beware of any static electricity build-up which can disable delicate electronics. Discharge any personal static before handling the board and contacts by touching nearby metal appliances or door handles. And keep the key fob’s interior electronic board far from clothing and carpet during the process.
Step-by-Step Guide: How to Change an Audi Key Fob Battery
By following these step-by-step directions closely, you can safely conduct an Audi key fob battery replacement procedure at home:
- Locate the screw securing the plastic casing on the backside of your key fob. It may have a small sticker over top of it you’ll need to peel off for access. Audi usually hides it discreetly behind the metal logo or a seam in the casing.
- Using your Phillips screwdriver, carefully turn the screw counterclockwise. Go slowly to avoid stripping the screw head. Once it’s loosened enough, pull it out completely and set it aside in a safe spot.
- Gently pry open the casing halves of the key fob. Start near the screw hole. Work your way around the outside edge, releasing plastic snaps until completely separated. Set aside the back cover.
- Slide out the used CR2032 coin cell battery. Notice which way it was oriented to allow smooth reinstallation of the new battery. If there are any signs of blue-green corrosion on the copper contact points from leaking battery acid, scrub the area clean using a paper towel, a toothbrush, rubbing alcohol and water. Dry contacts thoroughly.
- Check your new CR2032 battery’s polarity. One side has + marker; flip over to see the plain flat – side. Match against the installed battery’s orientation you just removed to verify which way to insert your new battery.
- Set your new CR2032 battery into place correctly based on verified polarity, with the + side facing up away from the circuit board. Press gently but firmly until the battery clicks and locks into its retaining clamps.
- Test operation by pressing your key fob’s lock and unlock buttons while the casing remains separated. Confirm new battery powers the fob properly before re-sealing the case.
- Rejoin the plastic casing carefully. Go slowly, watching to make sure interior parts align smoothly without pinching. Press firmly around all edges until snaps on the front & back click together securely.
- Replace the Phillips screw and tighten enough to avoid loosening over time. But do not over-tighten. Press the sticker back over the top screw opening if your model has one.
If the key fob fails to work correctly after replacing the battery, double-check for proper battery polarity/alignment. Try removing the battery, counting to 10, and then reinserting it to reset the fob. If problems persist, seek a professional diagnosis of your Audi key fob failure.
Other Key Fob Battery Replacement Options
While the above DIY method lets you swap a dead battery on your own quickly, some owners utilize professional services instead for the convenience factor.
Dealership Replacement Cost
Getting an official Audi dealership to handle the battery change typically costs $40-90 per key fob in total fees for parts, labor, and programming to sync the key fob with the car computer again.
Independent Mechanics
Many independent auto shops and locksmiths offer key fob battery replacements for much less, often $10-25 per fob. Shop around for quotes. But ensure they use a quality CR2032 replacement battery (not cheap knock-offs) to avoid fob issues cropping up again soon after your service visit.
Troubleshooting Audi Key Fob Problems
If replacing the CR2032 coin cell battery fails to restore normal functionality of your Audi key fob functions for vehicle access and operation, don’t give up hope yet. There are further troubleshooting steps to try before declaring your key fob broken for good.
- Check again for proper battery orientation matching polarity symbols for positive + and negative – sides.
- Remove and reinsert the new battery again after waiting 10+ seconds to reset the key fob system.
- Try replacing the battery with a different new CR2032 battery, even the same mAh & brand, in case the first new battery was faulty.
- Check whether the key fob battery retaining clips got damaged or bent. Gently straighten them to ensure the new battery makes solid contact.
- Examine the key fob antenna wire inside the casing for any visible damage or crimps which could interfere with signal transmission to your Audi.
- Consider shifting to the backup valet key with remote functions built into the traditional metal key blade. If it exhibits the same diminished range issues, your vehicle may need attention by your Audi service team rather than replacing more components on the main key fob itself. Schedule a service appointment and provide both keys for testing by the dealership technician.
Preventing Future Key Fob Battery Issues
To help your new replacement battery last as long as possible, follow this key fob care best practice checklist:
Extend Range & Battery Life
❏ Avoid storing fob near electromagnetic fields from electronic devices which can weaken the wireless signal over time and drain more battery power.
❏ Install fresh batteries annually as routine maintenance rather than waiting until complete failure.
Weatherproof Your Fob
❏ Keep the fob away from excess moisture and humidity exposure to prevent corrosion of interior electronics which hastens demise.
❏ In winter months, bring key fobs indoors rather than leaving them in extremely cold vehicles where batteries drain faster. Warm them gradually before use.
Have Backup Batteries
❏ Purchase 2-3 spare CR2032 coin cell batteries to keep in your glove box as replacements if the key fob ceases functioning when away from home tools and supplies. Dedicated fob batteries have greater capacity and shelf life than ones scavenged from other household electronics.
Frequently Asked Questions
Q: Why does my Audi key fob need a new battery so often?
A: Most CR2032 batteries last 1-2 years with average daily fob use. Extreme hot or cold temps, dropping the fob, water exposure, or proximity to electronics can shorten lifespan. Using fob functions more often drains a battery faster as well.
Q: Can aftermarket batteries damage my key fob?
A: Knock-off no-name batteries rather than quality name-brand cells often fail sooner or leak corrosive acid, so stick with Duracell, Energizer, or Panasonic CR2032 coins for best performance.
Q: Will dealership programming erase my programmed garage door codes?
A: Re-syncing your Audi key fob after any battery swaps or repairs should not delete your programmed HomeLink buttons which operate garage doors. But it’s wise to verify codes are still intact after getting key fobs back from any service visits.
Q: Do I need two working key fobs for driving the vehicle?
A: No. Only one functioning key fob is required to unlock doors, start the ignition, and drive the vehicle. But having a backup makes it easier if the first fob battery dies. The metal valet key in the fob can also access doors and start the car in an emergency.
Q: How do I get a replacement for a lost or stolen key fob?
A: Contact your Audi dealership with your VIN # and proof of ownership to order a replacement key fob programmed to work with your vehicle’s security system. Aftermarket/eBay fobs won’t sync properly. Expect to pay $200+ for a lost OEM Smart Key replacement.