1. Is it just one remote?
Try another remote, the keypad or the intercom. If everything else opens the gate, the problem is that one remote. If nothing works, the fault is at the gate: the receiver, the control board or the power.
2. Change the battery
The simplest fix, and the most common. A weak battery often shows up first as reduced range: the remote works right next to the gate but not from the car. Check the type printed on the old battery and replace it.
3. Check the range and interference
Remotes use radio signals, which can be blocked by cars, walls or new structures, or disturbed by other equipment nearby. If range has dropped for every remote, the receiver's aerial may be damaged or badly placed, which an engineer can fix or upgrade.
4. Has it lost its coding?
Remotes are coded to the gate's receiver. After a power cut, a battery change or a board replacement, some remotes need re-coding. On many systems this is quick for an engineer, and some owners can do it with the manual for their system.
5. Is the receiver's memory full?
Receivers hold a limited number of remotes. On busy shared gates, adding a new remote can fail because the memory is full. An engineer can clear out old or lost remotes, which also stops anyone using a lost one.
6. Replacing remotes
Replacement remotes must match your system. Look for the make on the motor or control box (FAAC, CAME, BFT, Nice and others). Older systems may no longer have remotes available, in which case a new receiver can be fitted so modern remotes work.