Android Signal Strength and Field Test Codes

Earlier this week Todd installed the iOS 4.1 Update on his iPhone 4 and reported that the field test mode that shows the actual cellular signal strength is back. The field test mode is not available in the initial release of iOS 4. I’ve written before that this type of reporting is important because the signal strength bars on most phones do not provide an accurate signal strength reading. Signal strength is reported in negative numbers, with lower the negative number the better.

Android does not require that you enter a similar code to see the signal strength as you can view it from within the phone settings. On an Android phone select Menu, Settings, About Phone, Status. The Signal Strength is shown as the fifth value on the screen. Even though signal strength is available within Android’s settings, there is a field test code that you can enter that provides more details about the phone status, along with battery information, usage statistics, and Wi-Fi information.

Before using the code I warn you to use caution as you can make some changes that will affect your phone’s performance. For example, I have found that if you change the preferred network type to WCDMA only, which means that it only connects to 3G networks, the phone will not connect to a network that only has Edge data service meaning you won’t be able to send or receive calls. The default setting is WCDMA preferred, which means your phone will use 3G if it is available, otherwise use Edge when 3G is not available.

To open the field test mode on an Android Phone, start the phone app, enter *#*#4636#*#* and after you enter the last asterisk a menu displays with options for Phone Information, Battery Information, Battery History, Usage Statistics, and Wifi Information. I found this code on a web page that lists a number of other codes that work with the Samsung Galaxy I7500. Use caution because some of the codes have the ability to wipe your phone. I tried some of the safer codes and found that they did not work on my Nexus One, though the field test code above does work.

Here is a quick summary of what I think is useful about each option:

– Phone Information not only shows signal strength but also shows information about how much data has been transmitted. It includes an option to run a ping test, which you can use to confirm that data network connectivity is working.

– Battery Information shows you specifically how much battery life is left along with the battery health and temperature.

– Battery History is useful in showing what is consuming battery life on your phone. This section actually provides a number of different usage reports by selecting items from a drop-down menu. For example, you can see which apps have used the most CPU and sent the most data on the network.

– Usage statistics shows which apps that you use in a number of different ways. You can see which apps you have used sorted by the longest amount of time, the most often launched, and alphabetically. I believe the statistics are based on since the last time the phone was restarted.

– WiFi Information has a submenu for Wifi API, Wifi Config, and Wifi Status. I think the Wifi Config option, which shows all of the WiFi networks that your phone is configured to use, and the Wifi Status, which shows you information about the Wifi network that the phone is current connected to, are the most useful options.