Update Galaxy S3 I747 to Android 5.1 Based PAC-MAN – How to

Apr 29, 2015

Official Pac-Man custom firmware has now been released for Android 5.1 Lollipop. Packed with a ton of features, Pac-Man has always remained one of a favorite custom ROM. Here is how to update Galaxy S3 I747 to Android 5.1 Lollipop based Pac-Man.

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Prerequisites to update Galaxy S3 I747 to Android 5.1 Lollipop:

Backup any important data from your Samsung Galaxy S3 SGH-I747 as a complete wipe will be required during the flashing process.
Enable USB debugging option on your device: Settings > Development Options > USB debugging.
Samsung Galaxy S3 must be rooted, unlocked and installed with a recovery tool like TWRP or CWM.
Your device must be charged to at least 60% of power.

Note: this tutorial is focused on AT&T Samsung Galaxy S3 SGH-I747; kindly do not try this guide on other Android & Samsung devices.

How to update Galaxy S3 I747 to Android 5.1 PAC-MAN:

Required files: download the PacMan Android 5.1 Lollipop custom firmware for Galaxy S3 I747 from here and save it on your computer. Also download GApps package. Do not extract the contents.

Connect Galaxy S3 to your computer using a USB cable and copy the zip file to your phone’s SD card.
Disconnect the USB cord and power off your Galaxy S3.
Boot it into recovery mode by pressing and holding Volume Up + Home + Power buttons together.
Perform a Nandroid backup of your current OS: Backup > backup and restore on ClockworkMod recovery.
Wipe data task: from CWM recovery menu, select wipe data / factory reset and confirm the process. Then go on to wipe cache partition and wipe dalvik cache.
From recovery menu, select install zip from sdcard followed by choose zip from sdcard. Locate the PAC-MAN Android 5.1 Lollipop custom firmware and confirm the flashing process.
Return back to main recovery menu and reboot your AT&T Samsung Galaxy S3 into the new custom ROM. First boot takes a good 5 minutes so please be patient.

How to restore: If you want to return to previous OS on your SGS3, boot into recovery, select backup and restore then restore your previous ROM by selecting it from the list.