The fix on this particular problem is best solved with a class 2 scan tool like the dealer has. The code must be cleared to see if it comes back on again, this must be done with a class 2 scan tool. If it does come on again you will need to replace the body control module. You can try a reprogram the theft detterent system now, by doing the following. If you decide to replace the body control module you will also need to do the reprogram procedure. Here is how.
30 Minute Learn Procedure
The vehicle learns the PasslockTM Sensor Data Code and/or password XXXXX the next ignition switch transition from OFF to CRANK. You must turn the ignition OFF before attempting to start the vehicle.
I hope this helps, good luck!