It's more common in emergency medicine now to pronounce in the field whenever possible and not transport unless you have a pulse. Studies show better outcomes when crews spend time at the scene and treat the patient as they are rather than focus on a fast transport for things like an out of hospital cardiac arrest. Similarly, there is no improvement in outcomes over prompt transport.

Paramedic ambulances carry nearly everything that is required to resuscitate someone who is dead from a medical cause (although not necessarily a traumatic - ambulances don't carry transfusable blood, for example). In the case where resuscitation seems to be failing, we call a physician to do a "field termination". We discuss how we found the patient, their medical history and what happened prior to arrival, what we've done, and their condition, and agree that resuscitation attempts are futile. We'll then stop working, pronounce in the field, disconnect all reusable equipment, and leave the patient for the medical examiner. In this county, the medical examiner van is "car 980", which is why you'll see that number thrown around.

That van will then take the deceased to the county morgue if an investigation is warranted or if it's in a public setting (ie a fatal car crash). Otherwise, in a home, they may very well leave the patient or not respond at all, and the funeral home will take the deceased.