owner before me said the cars oil was changed 1k miles ago but service light came on so wasn't thinking about it and reset it, i just wanna change my oil again to be sure i've only drivin less then 20 miles after i reset it if i change the oil and reset it again will it go back to normal and be accurate again???

 

Yes. Although 20 miles won't make any difference. But just reset when you get the oil changed and it will be fine.

 

It's not accurate. It's only a guess based on software. I never rely on any lights. I change by mileage and always between 6k-8k miles.
But if it's only been 20 miles since you reset it I would not worry about it. 20 miles either way won't cause any problems. So reset it if you want it won't make any difference.
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