Key Not Detected
The car can't see the key fob — usually a dead fob battery or the fob left outside the car.
What it means
The antennas that authenticate your smart key aren't picking it up. Common triggers: the fob battery is dying, the fob is in a bag blocking signal, it's sitting on the roof or was left behind, or interference from other electronics.
Can you keep driving?
If the engine is already running, most cars will keep running — but if you switch off without the fob, you may not be able to restart. Don't drive away from wherever the fob might be.
What to do now
- 1
Hold the fob directly against the start button (or the marked spot on the steering column) — nearly all cars have an emergency backup reader; check your owner's manual.
- 2
Replace the fob battery (usually a CR2032 coin cell) at the first warning.
- 3
If the fob is lost, a dealer or automotive locksmith can program a new one — proof of ownership required.
Likely causes
- • Dead or dying key fob battery (most common)
- • Fob out of range or shielded in a bag/pocket
- • Fob left outside the vehicle
- • Radio interference or faulty interior antenna
Typical fix cost
$3–$10 for a fob battery; $150–$500 for a replacement fob and programming
Ranges reflect mainstream US parts-and-labor pricing; your vehicle and region will vary.