Careless driving
130. Every person is guilty of the offence of driving carelessly who drives a vehicle or street car on a highway without due care and attention or without reasonable consideration for other persons using the highway and on conviction is liable to a fine of not less than $200 and not more than $1,000 or to imprisonment for a term of not more than six months, or to both, and in addition his or her licence or permit may be suspended for a period of not more than two years. R.S.O. 1990, c. H.8, s. 130.
Territory without municipal organization
If you have previous experience in traffic court, you may be comfortable defending yourself by challenging the particular elements of the offence as highlighted above. If it's your first time, you risk losing due to your own inexperience with the process. You don't want to risk high insurance rates for such a serious offense.
I think you have two choices:
1) pay for a lawyer to represent you (maybe $500-$600)
2) go down to the prosecutors office and talk to the Crown. It's quite common for the the Crown to propose a "plea bargain" (to avoid a costly trial). If you have a clean record, one minor conviction probably won't affect your insurance rates (for the next 3-years). So you may wish to have the Careless charge amended to just the stop sign charge ($115/3 points). I have 6 more months to go on MY stop sign charge before I'm "clean" (takes three years). I plead away TWO other charges to avoid trial. My insurance never went up though my company was well aware of the conviction.
In order to have more time to research your options, you should plead not-guilty on your ticket and get it to the courthouse within 15 days of the offence. Then sit back and wait for your court date to arrive in the mail.
Careless Driving has to be one of the most "wishy-washy" charges in the HTA. It's so vague and can be applied to almost anything. I have some case-law on the subject at work. I'll follow up with more info when I review it (over the next day or two).
Don't panic