999 phone charging myth
The 999 phone charging myth is an urban legend that claims that if a mobile phone has low battery, dialing 999 charges the phone so it has more power. This was confirmed as untrue by several British police forces, which publicly cited the dangers of making such calls.
Basis
The basis for the belief was a feature of BlackBerry phones: if the battery level was too low, the phone automatically locked down phone features and shut down the phone radio for all calls except to the emergency services. Phone users in the United Kingdom discovered that if they dialled 999 then immediately hung up, it would override the shutdown for several minutes so that phone calls could be made. The belief seems to have originated in UK BlackBerry forums around 2012.In 2015 telling Siri on an iPhone to "Charge my phone to 100%" would cause the phone to call the emergency services as a secret safety code. This was later traced to a bug in Apple programming that was fixed within a day. The urban legend continued to spread on social media as a prank.