The remote control does not lock or unlock the doors.

Symptoms

["Remote control battery is flat: Use the emergency key.", "Use of appliances on same frequency: Stop using the devices or use the key.", "Vehicle in high electromagnetic radiation zone / Discharged battery: Replace the battery. You can still lock/unlock and start.", "Desynchronisation of the remote control: Unlock the driver’s door by inserting the key, then start the engine to synchronise."]