What causes the oil change light to come on?

Read time: 2 minutes

Answer: The oil life monitor.

All right, let’s talk about this monitor. Modern-day vehicles have an oil life monitor that uses a complex algorithm to calculate the wear and tear on your oil from day-to-day use. This algorithm takes into account engine load, oil temperature, engine temperature, average vehicle speed, ambient conditions, and so on. And, it uses this information to calculate engine oil life.

There are a few pros and cons to this oil life monitor.

Let’s start with the pros

PRO: It maximizes the oil change interval.

The oil life monitor determines the frequency of an oil change based on individual driver use. Some people will have shorter oil change intervals and others will have longer ones. It all depends on driving habits and conditions.

The monitor will make sure your oil is performing at optimal performance for your engine, therefore, maximizing oil life usage and, in some cases, reducing maintenance costs.

PRO: It remembers your oil change for you.

Yep, modern technology is great, isn’t it? You no longer have to remember when you’re supposed to get your oil changed. If you have an oil life monitor, your vehicle will give you a percentage of oil life left and warn you when your oil change is due.

And now, the cons

Well, one con, really.

The con of the oil life monitor system is that it has to make some assumptions. And we all know what happens when we assume. These assumptions are oil quality, oil level, and the fact that when the change oil light comes on you’re actually getting your oil changed.

Turn these assumptions into facts, and make sure your shop uses an engine cleaner like BG EPR® and then reinstalls quality oil with an oil protectant like BG MOA®. Most importantly, make sure your engine stays full of oil.

basically, listen to your monitor.

My parting words of wisdom: when your vehicle warns you it’s time to change your oil, listen to it. When it says there is 0% oil life left that is exactly what it means… and you should take it seriously.

This has been a friendly public service announcement from Tom Probus, CD (Car Doctor).

Tom Probus, Automotive Research Specialist, BG Proving GroundBy Tom Probus
Automotive Research Specialist, BG Proving Ground
Tom Probus is an ASE Master Technician and has been ASE Certified for more than 20 years. He joined the BG Proving Ground in 2015, where he helps invent new equipment that keeps BG at the top of the industry.

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