Unnecessary technology in automobiles hurts fuel economy greatly!!!
Just like running your A/C, other electronic devices pull hard on your car's alternator. Thus, reducing your car's overall miles per gallon.
I have made a hobby out of improving my car's efficiency by eliminating some of these would-be leaches of power. For instance, Daytime Running Lights. While required in some areas, many view them as only necessary during near-dark conditions. To respond to the requirement, many auto manufacturers have made their cars and trucks to utilize them constantly while they're running. Daytime running lights can use up to 2% of your overall fuel economy. Keep in mind, the fact that they aren't always necessary or an addition to safety.
I live in Florida, one of the sunniest places in the US. I rarely drive at night and thus was in a pickle about DRLs. Because my volkswagen was programmed to run them constantly, I did some in-dash tweaking to my car and saw a gain of nearly 1/2 a mile per gallon!!!
According to a research study, if every car in America shut off their DRLs, millions of gallons of gas would be saved.
Check out this article: