The service stabilitrack, and service traction control light comes on whenever the engine throws a code, or ABS system throws a code to my understanding. atleast whenever a module is in any way related to the vehicle possibly mis reporting engine conditions so it can make wise (computer) decisions as to how to correct the traction.
So one would see the traction control, and stabilitrack service lights any time you have a code related to the above mentioned. So the traction/stabilitrack light is not a diagnosis in any way, its almost exclusively a symptom of another problem that means you need to check your codes.
If your check engine light comes on, your lucky, because now you can read a code with a simple code reader that you can follow that will probably lead to a proper diagnosis.
If you dont see a check engine light, then now you need to go the dealer because they can read codes above and beyond with their almighty expensive equipment.
The code must be noted, and that will lead to why the traction/stabilitrack lights are on.
get this code, and post it here. thats the best way anyone can help normally.
as far as the EGR, i had a code for this when my stabilitrack.traction light would not go off, p0405 low volts egr circuit, need schematic or experience on 12v feed circuit
and was able to solve my problem entirely much the same as JBINKLEY06 it appears.
You will find that any car has its problems. The beauty in modern technology is we have diagnostic lights to give us early warnings, and computers that give codes to follow. the caveat is it leads to confusion at times. :-)