Why is My Check Engine Light On?

October 17, 2023

Chula Vista Drivers Ask: Why is My Check Engine Light On?

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

First, if your check engine light is flashing, that means that something is wrong that could cause severe damage to the catalytic converter or other components. Get that taken care of right away. If your check engine light is flashing, you shouldn’t drive at highway speeds, tow or haul heavy loads. Take it easy all the way to the service center.

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 service advisor to get it checked out.

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

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 Check Engine Light.

The computer will also try to adjust 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 service technician 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.


Bonita Point Auto Care, Inc.
1495 East H Street
Chula Vista, CA 91910
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