On an iPhone, dialing *#31# is used to check the status of Caller ID settings. Specifically, it lets you find out whether your outgoing calls are set to display your number or not.
- If Caller ID is enabled, your number will be shown to the person you are calling.
- If it is disabled, your number will be blocked and will not appear on the recipient’s phone.
Note that the effectiveness of this code can vary depending on your carrier, so it may not work universally. Additionally, you usually find options to manage Caller ID settings within your phone’s settings under the “Phone” section or you can contact your carrier for more specific management options.