UWB Keyless Entry: Does Your Car Still Need a Faraday Pouch?

If your car uses UWB (ultra-wideband) keyless entry, relay attacks are a much weaker threat against it — and a shielding pouch is far less necessary. We sell those pouches, so here is the honest version: how UWB defeats relay attacks, which makers use it, how to find out what your car has, and the 30-second test that settles it regardless of any spec sheet.

Why UWB Defeats a Relay Attack

A relay attack works by carrying your key fob's signal from your house to your car. Older keyless systems only ask "can I hear the key?" — so a relayed signal looks genuine.

UWB asks a harder question: how far away is the key, exactly? Per the FiRa Consortium, the UWB industry standards body, the system "measures time-of-flight (ToF) with such precision" that it "can reliably detect whether the device is truly near the vehicle, not just relaying a signal from afar", using two-way ranging and timestamp verification.

Relaying takes time. That added latency makes the key look further away than it is, and the car refuses. This is why ADAC's testing found that with UWB systems, the car simply "no longer responds" to their relay equipment — the only technology in their programme that held up.

Which Cars Use UWB

We are not going to publish a model-by-model "safe list", and you should distrust any site that does. UWB availability varies by model year, trim level and market, changes between facelifts, and is sometimes tied to a digital-key option rather than the standard fob. A list that's wrong tells someone they're protected when they aren't.

What is solidly sourced:

  • Jaguar Land Rover implemented UWB from 2018, with Audi, Volkswagen, Škoda and Cupra among those following — per ADAC.
  • BMW markets its Digital Key Plus as UWB-based.
  • Adoption is being driven by the Car Connectivity Consortium's Digital Key certification, which expanded to cover UWB following the FiRa 3.0 Certification Program in January 2025.

How to Find Out What Your Car Has

  1. Check the handbook or build sheet for "UWB", "ultra-wideband", "Digital Key Plus" or "CCC Digital Key".
  2. Ask the dealer for your VIN's specification — not the model's brochure. Trim and market matter.
  3. Look at how the key behaves. Systems tied to a phone-as-key with precise proximity unlocking are more likely to be UWB than an older fob-only system.
  4. Then ignore all of that and run the test below, which tells you what's actually true for your car today.

The 30-Second Test That Settles It

This is ADAC's own recommended method, and it works whatever the spec sheet claims:

  1. Have someone hold your key fob inside the house, well away from the door — or seal it in a shielding pouch or metal tin.
  2. Stand at the car, about a metre away.
  3. Try the handle and try to unlock.
  4. No response = the signal isn't reaching the car. A response = it is, and a relay attack has something to work with.

Repeat with the fob in each place you normally leave it — hall table, kitchen worktop, coat pocket by the front door. Distance from exterior walls and windows matters more than most people expect.

Honest Limits

  • UWB raises the bar; it doesn't make a car theft-proof. Thieves also use OBD-port attacks, key cloning, and simply towing the vehicle. Shielding a fob addresses relay attacks specifically.
  • Security implementations get patched and occasionally get broken. Treat "my car has UWB" as strong protection against this one attack, not permanent immunity.
  • Two-car households are mixed. A newer UWB car and an older keyless car on the same key rack means the older one is still exposed.

So Do You Need a Faraday Pouch?

Probably not, if your car is confirmed UWB and passes the test above with the fob in its normal spot.

Probably yes, if your car is keyless without UWB, you can't confirm what it has, your fob lives near the front door, or you want the fob shielded wherever you set it down. In that case see our pouches and boxes for car keys — or, per ADAC, a metal tin works too; the test is what matters, not the brand.

Using This Page

Journalists and club editors are welcome to cite this — please credit FiRa Consortium and ADAC and link to their pages.

Related Reading

Relay car theft: what the data shows · What actually stops relay theft · Relay attack (glossary) · How we write & what we don't claim