Finding the ECID for the iPhone 3G S
Updated: November 13, 2009
Turn off the iPhone. Once it is off, press and hold the Home button.
Plug in the USB cable to your iPhone and your computer, while holding the Home button. The Apple
logo will appear on the iPhone, then the recovery mode graphic will appear.
iTunes will launch and display a pop up message about recovery mode. Click OK on this message.
Click the Apple logo in the menu bar on your computer. Select About This Mac.
Click More Info...
In the Contents section of the screen, go to Hardware and expand this menu if it is not already.
Go down to USB and highlight it. Go to the USB Device Tree section of the screen. Go to USB
High-Speed Bus and open this menu if it isn't already open. Click on the line that says Apple
Mobile Device (Recovery Mode). Look below, and in the line that says Serial Number, look for the
letters ECID. The 16 characters after the colon are your iPhone 3G S' ECID number.
Write this number down for future reference. Apple may try to obfuscate this number in the future.
To get your iPhone out of recovery mode just hold down the Power (sleep/wake) button until it shuts
off. The iPhone will reboot.