I had the codes run on my 2005 limited convertible today and it came back with:
B1226 - In car temperature sensor
B1231 - ECT sensor (coolant temperature sensor, apparently)
B1421 - Pulse Module

I've done some research and I don't see any guides that explain exactly where these are and if I can replace them or I need to have it serviced. I also have codes for the convertible mechanism, but, I'll post that separately.
Thanks,
- Brian