If you do not properly warm up the 2004 rotary engine in this car ( and I mean actually driving it) until proper driving temp, it will flood. Happened to me 2 times within 3 months. The first time I didn't know better and just let it idle to warm. 2nd time my friend was convinced he could move it from outside the garage to inside the garage in a snowstorm. The second time around, I learned how to deflood my own engine b/c repairs are about $700-800 :-( to basically replace 4 spark plugs.
I did find this on a Mazda forum:
TCM U0100, RAW: C100, Meaning: Lost Communication With ECM / PCM A"
but none of my other information gives any information on this code. If you have your car at a repair shop and they are stumped there is a professional service called Identafix. http://www.identifix.com/info/about_us.htm They only deal with professional repair shops. They are in the Minnesota 651-633-8007 begin_of_the_skype_highlighting 651-633-8007 end_of_the_skype_highlighting. Your auto repair shop do all their diagnosis tests, and discuss your problem with a team of professional technicians great service cheap and very bright people.If the repair shop that are repairing your car are stumped this is a great service. This company only deal with automotive repair shops and don't answer questions for the general public but are an amazing knowledge base.