What does a service engine soon light mean?

April 1, 2021

I’m pretty sure we’ve all seen this light come on at least once or twice in our lives. Either in our vehicle or family and friend’s vehicle. Some may even cover the light with a picture or scrap paper to bring a sense of relief we call “Out of sight, out of mind.” 


I know that may give you a temporary feeling of peace of mind, but let’s go over what this light means so you can get it in the shop instead of pasting over it!


The service engine’s soon light’s function is to let the driver know that the vehicle’s sensors have picked up on an issue. The emission control system often triggers this light, but other various causes could activate the sensor. Seeing this light come on can cause some alarm, but all cars need maintenance, and it doesn’t mean your engine is broken or cause for panic.


If the service engine soon light comes on while you’re driving, it’s best to pull over and assess the situation. Sometimes it can be a simple fix. Since the emission control system often triggers the sensor, it could be that you didn’t tighten your gas cap after fueling up, or it’s missing. If the fuel cap isn’t sealed correctly, it can easily trigger the sensor, so that’s an excellent place to start. It could also be as simple as one of your fluid levels is low. Be sure to check your oil and coolant levels. Being low on one of those fluids can cause some significant problems for your engine and radiator.


Another common issue that causes the service engine soon light to come on is the oxygen sensor, also known as the O2 sensor. The oxygen sensor monitors the way unburned oxygen is expelled into the environment. Ignoring a damaged O2 sensor can ruin your vehicle’s catalytic converter, resulting in even more damage that can easily wrack up your mechanic bill.


Also, be aware that your vehicle isn’t in immediate danger of significant issues unless the service engine soon light is flashing instead of solid. That’s not to say to ignore the light, since they’re still very well could be an issue. It just means you should be able to drive to your mechanic safely. If it is flashing, it’s recommended to cease driving, call for roadside assistance, and get towed to your mechanic.


If your vehicle has not been maintenanced or inspected recently, schedule an appointment with John’s Automotive Care in La Mesa. Our entire team takes pride in keeping you updated throughout your service. Our community of customers trusts our commitment to quality auto repair. If your vehicle needs preventive maintenance or repairs, call John’s Automotive Care or schedule an appointment online with us today to experience the John’s Automotive Care difference. We are located at 7447 University Ave, La Mesa, CA 91942


We look forward to your visit!

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