Kaiwan

I have a 94, GS300. Three months back i started having problems with the Track light staying on all the time. The light comes on after you have driven it for a minute or two and stays on. I took it Lexus dealership and they told me that they cannot retreive the codes as they don't register in the computer module. It seems that the computer module is fine and maybe something else. Do any of you had the same problem. I am in Houston any help would be appreciated.