If you co-signed the loan for her vehicle and it goes bad, both of you will be responsible to pay the lender back. You need to look at this co-sign as if you are taking out the loan yourself. If your daughter doesn't pay and the lender sues to collect, you could get hit with attorneys' fees.
Does your daughter have the title and insurance in her name alone? If so, only the your daughter, the owner of the vehicle, and driver can be held liable in an accident. Your co-signing of her car loan does not make you an owner nor does it make you liable. So long as you are not listed as the registered or titled owner of the vehicle, you should not have liability for any accident your daughter may have.