Physical barriers between the key and the car may have an adverse effect on the range or completely block the signal.
Using the key's buttons
The key's functions that are controlled by pressing a button have a range of approx. 20 metres (65 feet) from the car.
If the car does not verify a button being pressed - move closer and try again.
For keyless* use
For keyless use, a key must be within a distance of approx. 1 to 1.5 metres (3 to 5 feet) from the car's doors or boot lid.
Note
The key functions may be disrupted by surrounding radio waves, buildings, topographical conditions, etc. The car can always be locked/unlocked with the key blade.