What is PIT File:
A PIT file is basically a set of instructions defining the Samsung phone partition layout. Technically, you need to use the PIT file only if you want to Re-Partition your Samsung phone. Otherwise, No need to use it, So you will keep the current partitions of your Samsung phone.
How To Use Samsung Galaxy Trend 3 Duos SM-G3502 PIT File:
To use the PIT file you need to have Odin3 flasher, The Odin3 flasher is the Original flasher for Samsung Android Smartphones and Tablets, So if you do not have it, Then you can download it from the links below.
Run Odin3.exe program, In case you are using WIN 7 PC, Then you have to run Odin3 flasher as Administrator, After that click on PIT button and select CS023g.pit file.
Now to tell Odin3 to use this CS023g.pit file, You have to Check RE-Partition option at Odin3 program. Now all you have to do is to put your Samsung Galaxy Trend 3 Duos SM-G3502 into Download Mode.
Use the USB cable to connect your Samsung Galaxy Trend 3 Duos SM-G3502 to PC, Samsung USB driver must be installed to let your PC recognize the Samsung phone.
After Odin3 flasher detects your Samsung Galaxy Trend 3 Duos SM-G3502, Click on Start button, And Odin3 will use the CS023g.pit to Repartition your device.
Download Links:
Samsung Galaxy Trend 3 Duos SM-G3502 CS023g.pit file (Download).
Odin3 v3.10.0 (Download).
Samsung Stock ROMs and Firmwares ( Download).