To complete the Preferred Roaming List update: Call *228 from your home coverage area.When prompted, select 2 to update your phone's preferred roaming list.Before you start Many LTE devices can run this update over Wi-Fi but if you're having trouble getting the update to start, or it fails before completing, you may need to disable Wi-Fi and enable data instead.Also, make sure that you're in an area with good, strong signal when you try this update.Over the air updates are important because they synchronize your phone with the network.If you've ever had an issue where your phone isn't successfully connecting to the network even though you're in a good coverage area, there's a strong chance that an over the air update will get your phone working again.If you own a CDMA version of the i Phone, you can update your roaming capabilities by dialing a number from your phone directly, which can increase your battery life while roaming, allow your i Phone to connect to additional roaming networks and decrease the amount of blocked and dropped calls.
A PRL update provides your phone with the most up-to-date info regarding roaming and the roaming network.
The Preferred Roaming List (PRL) is a database residing in a wireless (primarily CDMA) device, such as a cellphone, that contains information used during the system selection and acquisition process.
In the case of R-UIM-based CDMA devices, the PRL resides on the R-UIM.
Hands free activation, profile and PRL updates are the most common forms of over-the-air update, and all of these updates are initiated from your phone with either a restart or by selecting the appropriate option in the settings menu.
A profile update synchronizes your phone with the network by updating its network access info.