BMW group tester one (GT1) is offered to the aftermarket in the same specification that is currently supplied to BMW franchised dealers. It is special-purpose tool of BMW Series:
Gt1 is supplied with a Pentium based laptop PC on a Windows platform connected to a high specification communications and measurement interface.
GT1 can complete coverage of ALL BMW systems, one thing that can only be done using the GT1, this function is called Electronic Control Unit (ECU) programming and configuration. Many of the original electronic systems on modern vehicles can now be re programmed using software; historically any changes to rectify software problems would involve a new ECU which would be purchased from the parts department and that is the only way that the independent market today is able to overcome these problems. The BMW GT1 system allows you re programme all BMW car ECUs to fix software or to install a blank ECU to a repaired vehicle. GT1 is the only system that allows you to do this and is absolutely essential if working on Freelander , the GT1 is also the only system that provides all diagnostics and programming for the very latest BMW launched this year.

BMW GT1 software kit comprises of five system ,TIS system .DIS data system ; diagnosis system .measuring system and manangement system . you can to test and check data information same time in GT1.