Thanks for the info but I'm unsure if there is a "real" fault or not. As I said it came up the same time I was having electrical issues and before I start spending money I was hoping to clear it and see if it sets again.
It is possible my code reader will not read these codes. I have seen a simular post for a 2000 Bravada where they state you can read the code by grounding the #13 wire on reader plug and watch the lights flash. I was going to try that but on the 99 there is no wire in the #13 position, so that will not work.
I realize it is supposed to come on when there is a problem with the system, however I think this one is a fantom and just want to clear the TCCM code and see if it remains off or if there truly is a problem.