One problem related to anti-theft controller has been reported for the 2003 Chevrolet Suburban. The most recently reported issues are listed below.
The anti theft system caused the engine to quit going down the hi way several times and was very dangerous some of the times and left us stranded sometimes. Gm acts like they do not know what is wrong but there is ample info on the internet and even a fix but it disable the ats, it turns off the fuel to the injectors killing the engine. This happened many times. We had to be towed twice because it would not restart.