Which engine group do I have? This question comes up so often that I wanted to post this in tip format. 

Enter the imobilizer and look in the data stream. You will see the engine and control number listed. Use this number when selecting engine. (ie B5254T, B5254T3, B5254T4 ETC)
If the wrong group is selected the controls will behave unusual and the data may be listed in error.

Best wishes

excellent!..thanks

Excellent information Coyote, this is definitely a critical step to getting into Volvo's. Much easier than checking that timing belt cover.