[Galaxy S 5 Q&A, Help & Troubleshooting] ad0dh67:
you could try google sometime, its almost your best friend :thumbup:

The Customer Service Code (CSC) plays an important role in the operation of your Samsung mobile device. Different countries have different standards for both voice and data communications to a cell phone tower. Although most countries follow the international standard for WiFi connects, there are variations from the standard. The CSC code ensures that your mobile device complies with the standards for your country, and your cell phone operator. The CSC code also determines the source for firmware updates via FOTA*or Samsung Kies.

The terminology used by various Internet sites is confusing. The CSC firmware code contains a number of fields, including the model number,*product code, and build date. The three characters after the model number are the product code. However, the product code is also called the CSC code, country code, or sales code. In actuality, the product code is either a sales code that defines the actual vendor, or a multi-csc code that represents a group of sales codes. Following are the possible scenarios:

The product code is a sales code that identifies a specific cell operator. This code is called a branded code, as the device boots with the operators logo, and contains operator apps.The product code is a sales code that is an open (unbranded) code. With this code, the device boots with the Samsung logo, and only includes Samsung apps.The product code is a multi-csc*code. These codes are commonly used for phones sold by independent vendors. Your mobile device still needs a source for software. The*/system/csc/sales_code.dat*file defines the sales code used for software updates. The easy way to get this information is with the "Phone INFO" app. The multi-csc group must include this sales code. The sales codes can be:The code is the open / unbranded code for the same country.

Warning!!!

Changing the CSC / product code on your Samsung device may invalidate the warranty. It may also invalidate the Samsung Knox warranty for Samsung devices

that support Samsung Knox. Furthermore, there is no guarantee that flashing new firmware will work, even when you flash valid firmware.

In many cases, flashing the sane firmware a second, or third, time may work.

Following are examples of cases in which you may want to change the CSC / product code:

If you move to another country, you may wish to change the CSC / product code to one that matches your new home. You just need to remember that not every Samsung model is sold in every country. Furthermore, not all models are available for every sales code, including the open (unbranded) codes.If you purchased a branded phone, you may wish to change the CSC / product code to an unbranded sales code. Again, there is no guarantee that an unbranded version of firmware exists for your model that is compatible with the cell phone frequencies in your country.You may wish to upgrade to new a new version of Android that is not yet available from your current sales code.

Following are some guidelines for selecting the correct firmware:

Use the "Phone INFO" app to obtain information about your current firmware. I recommend exporting the information, and printing the resulting text file. Should you need to restore the current firmware, you have a log of the current firmware values.You must use firmware that matches the model number, including all sub-codes. For example, the Samsung Galaxy S5*has more than 15 different model numbers. Each model was built for a specific market, and often has slightly different hardware. Some cell phone operators have custom models that only work on their cellular network.Unless you must have firmware branded by a specific cell phone operator, I recommend using firmware from and open (unbranded) sales code. The*sales code table*will help you find these codes.If your current phone has a multi-csc code, your best chance of finding the correct firmware is to select an unbranded sales code that uses the same multi-csc code. The*multi-csc table*list the sales codes that are members of each multi-csc group.For firmware that uses a multi-csc code, you need to select a sales code before attempting to connect to a cellular network. This is especially true for 3G and 4G connections. There are two ways to select a sales code:Enter *#06# in the phone dialer to obtain the IMEI number for the device. You can then enter *#272*Device IMEI# to select a sales code. If your Samsung device does not return a menu, the product code is not a multi-csc code.Install an CSC changer app, such as the "Phone INFO"*app. CSC changer apps do require root access, and they do not work on all phones and all versions of Android