Nearly every new car has a standard or optional blind-spot detection system. The complex systems use cameras or radar to scan adjoining lanes for vehicles that are hiding from the driver’s view, but if you setup your mirrors correctly you shouldn’t have any blindspots and these systems should be redundant at best. It takes zero effort to do it right, but almost everyone does it wrong.
Blind spots can be put into full view of your side view mirrors by simply adjusting them so that no part of your own car is visible. It’s really that simple. Angle them away from you until the point where your car is no longer visible in either one, and your done. That leaves no overlap between them and the rearview mirror and maximizes the angle of view you get out of the side mirrors. Any car that’s passing you will remain in either your rearview or side-view mirror until it enters your field of vision. This also allows you to stop pulling the over-the-shoulder before changing lanes move which effectively pulls your eyes off the road for a second or two.
Admittedly, writing about this topic seems stupid, but no one does this right. Manufacturers put all this blindspot tech in their cars but it’s all unnecessary if you just setup your mirrors correctly in the first place. You can now skip the $1500 driver assistance package. Here’s a helpful graphic from Car & Driver: