Question: I want to reset my car’s computer. How can I do that, and how much will it cost?
Answer: I’m not sure about what your motivations are for resetting your car’s computer, but I had a situation where I was resetting it once in a while until it became unsustainable.
See, my check-engine light came on, and I went to a mechanic to get it checked. The mechanic told me not to worry as it came from a faulty oxygen sensor. The car was old and I was going to get rid of it soon, so I didn’t bother repairing the problem.
Visit a mechanic (paid)
My mechanics cleared the codes, and I was on my way. So, there you have one way of resetting a computer: Ask a mechanic. It did cost me some money to get the diagnosis, but the assurance I got from a mechanic clearing the fault was very valuable. Had they said it’s something critical, I would have had it fixed.
Pull a fuse (free)
However, a few weeks later, the check-engine light came on again. It immediately irritated me, and I found a fuse that I could pull out to get rid of the problem. I removed the fuse temporarily, and after replacing it, the check light was off. This cost me nothing.
Disconnect car battery (free)
When changing my car’s battery, I noticed a much bigger reset. A battery disconnected for even a moment causes a lot of electronics to lose their memories. This resulted in higher idling RPMs and the loss of my radio presets and air conditioning settings. The idling RPMs eventually recalibrated and settled down to what they used to be. So, here’s another free way to reset your car’s computer.
These two home-based methods were great and cost nothing, but popping the hood, pulling a fuse, waiting then reinstalling it became a hassle. As the deteriorating oxygen sensor got worse, it also caused more frequent check-engine alerts. Disconnecting the battery was a worse idea because I’d lost a lot of settings.
On-board diagnostics scanners might help
I toyed with the idea of buying an on-board diagnostics (OBD) scanner that would allow me to check the error codes, and while some sell for as little as $10, I learned that not all of them can reset a car’s computer. This varies from vehicle to vehicle and unit to unit.
How it ended
Eventually, it became more tolerable to just ignore the check-engine light than it was to reset the computer every time. I was well aware that the light could be displaying a new fault code with me thinking that it was still the oxygen sensor. However, the car was promptly sold, and the new buyer was made aware of it. If I wanted to keep my car longer, I would have fixed the oxygen sensor or asked the mechanic for updates every time I visited for an oil change.
Xuyun Zeng is a content strategist with a wide-ranging content background including tech, journalism, cars and health care. After graduating with highest honors in journalism, Xuyun led a newspaper to win eight awards, helped start an award-winning film industry podcast and has written over a hundred articles about cars repair, state laws and insurance. Prior to joining Jerry, Xuyun worked as a freelance SEO consultant with a mission to create the best content that will help readers and grow organic traffic.
Phil Metzger is a personal finance editor and writer with more than 30 years of experience editing and writing content across a variety of industries. In writing and editing for Jerry, Phil’s mission is to help car owners better understand their vehicles and the costs associated with car ownership. Before joining Jerry, Phil worked as a writer and editor for newspapers, magazines, television radio and online news. His work has appeared in many major publications and websites over the years, including a series he edited that was a finalist for a Pulitzer Prize.
