A traffic accident in a dream is symbolic, not a warning of a real one. Tradition reads it as a clash of plans or wills, or as fear of losing control when life moves too fast.
When this appeared in your dream, what were you feeling?
My Cosmic Code has a private dream journal. Write a dream down and the app picks out the symbols in it, shows what dream books say about them and, over time, which words recur across your entries. The journal is stored on your device only.