Back to all

Why Is My Check Engine Light On?

March 26, 2020

The Check Engine Light strikes fear into the hearts of some Commerce drivers, and is totally ignored by just as many. Just what it means is a mystery to most people.


Let's get the urgency issues out of the way first. If your Check Engine light is flashing, that means that something is wrong that could cause engine damage. Naturally, you need to get that taken care of right away. If your check engine light is flashing, you shouldn't drive at high speeds, tow or haul heavy loads. Take it easy all the way to your Commerce service center.

drive

If the light is glowing steadily, you should keep an eye on it for a day or two. If the light doesn't go off, schedule an appointment with your friendly and knowledgeable pros at Commerce Auto Repair to get it checked out.

Some more information on how the Check Engine light works may be helpful for Commerce drivers. Most of your engine functions are controlled by a computer, not surprisingly, called an engine control computer. The computer is able to adjust many engine parameters for environmental conditions, engine condition and even the way you drive.

In order to make these adjustments, the computer relies on a network of sensors to provide data. The computer knows the proper operating range for each sensor. When a sensor reading is out of range, the computer runs some tests and may turn on the vehicle's Check Engine light.

A simple example is a loose or missing gas cap. This may cause one of the sensors to read out of range. The computer doesn't know if it's a serious condition that caused the reading or just a loose gas cap, so it stores a trouble code and turns on the Check Engine light.

Now when you tighten up the gas cap, the sensor readings will be in the correct range. The computer will keep checking on the report for a day or two. Since a bad reading didn't come up again, it turns off the Check Engine light. The computer will also try to make adjustments to compensate for some readings. If it can do so, it'll then turn off the Check Engine light.

If the problem can't be resolved then the light will remain on, and you should get your vehicle looked at. Your friendly and knowledgeable pros at Commerce Auto Repair will plug a scanner into the on-board diagnostic port and read the trouble code stored in the computer. The trouble code will give the technician a starting place as he diagnoses the cause of the problem.

 

Commerce Auto Repair
9575 Commerce Rd.
Commerce, Michigan 48382
248.363.3749

Need Service?

Request a Quote

More articles from Commerce Auto Repair

A Most Important Part (Serpentine Belt Replacement)

October 27, 2025

Your vehicles engine is an engineering work of wonder with many complex parts working in harmony to get you down the road. One of those simple but important components is called a serpentine belt. It is driven by a pulley on the engine and transfers that power to many of your engines most importa... More

(Ball Joint Replacement)

October 23, 2025

Every day that goes by, our bodies get a little more wear and tear on them. Our vehicles have the same issue. The older we get and the farther we travel, certain parts start showing some wear. Think of your hips. There are parts of our vehicles that are similar to them; just like hips allow y... More

See the Light (Bulb Replacement)

October 12, 2025

When you notice one of your headlights has gone out, its important for the safe operation of your vehicle to get it changed and working again. Not only is replacing a headlight important for your ability to see in the dark, but its also vital that it be lighting your way and aimed correctly so o... More