My turn signals only work if I push the hazard switch in I have no hazards at al

I'm not sure if the CEM controls this system...best to look at a wiring diagram to verify. The CEM is normally programmed to work on a specific car, so installing a used one rarely works. These early S40s are unique in that they blend old-school electronics and new...so the solutions are both old and new...start by diagnosing with a wiring diagram and see where the signals are getting lost.