How keyless works
Antennas around the car send a low-frequency 'are you there?' signal. Your key answers by radio, the keyless module checks the answer, and the car unlocks or starts. If any part of that conversation breaks, you'll see "Key not detected" or "No key found" on the dash.
It's not always the key
A flat key battery is the usual suspect, but a weak car battery, a module that's lost sync after a battery change, or water in a junction box can all cause the same message. We test the whole chain before selling you a key you don't need. See our Jaguar XF 'Smart Key Not Found' guide for a classic example.
Questions people ask
Can you program a keyless key without the dealer?
Yes, for the vast majority of cars. We read the security data from the car and program the new key on site.
My car says key not detected but the key works sometimes?
Try a fresh key battery first. If that doesn't fix it, the fault is often in the car's keyless module or antennas, which we can diagnose on site.