An update: In addition to the check engine light and the coolant level sensor being on, my battery light turned on, the dashboard lights dimmed, and the airbag light flashed a couple times. Figuring that I had a bigger problem than I could handle on my own, I brought the car to the mechanic.
They found that the wiring near an O2 sensor had lost insulation and was grounding out - kudos to you for the excellent guess!
They charged me to replace both O2 sensors and the alternator - does that make sense to you? I can see how one O2 sensor had to be replaced, and maybe the second as well because they have to both be replaced as a pair? Or maybe the shorting broke both sensors? I can also see how a bad alternator would cause the battery problem, but I wonder the wiring shorting out could have done the same thing. I guess the shorting could have affected the alternator as well.
Friday, February 3rd, 2017 AT 7:31 AM