Check Engine Light On? Don’t Panic!

Beginning in  1996, automakers standardized diagnostic codes under the OBD-11 protocol. Cars manufactured in the 1996 model year and beyond are equipped with a standardized set of fault codes, along with a universal port for easily accessing the diagnostic system.

If the car’s onboard computer senses a fault in any of the emission or engine systems, it will generate a fault code which in turn will trip the dreaded “check engine” light

Along with standardized codes and universal diagnostics comes that universal pit in the stomach the second that light comes on.

What Exactly Does The “Check Engine” Light Mean?

For openers, there are two lights: one for servicing, and the “check engine” light. Many drivers confuse one for the other, but they’re two separate lights. One is a service courtesy light (“service due soon”), and the other indicates potential trouble with one of the car’s systems.

Some of the more common triggers for the “check engine” light:

• Faulty oxygen sensors
• Faulty ignition coils
• Fault in mass airflow sensor
• Fuel injector issues
• Thermostat issues
• Transmission issues

Before you panic, check your gas cap. Loose gas caps are a common trigger for your “check engine” light. Tighten the gas cap and allow some time for the “check engine” light shut off.

Transmission sensors are especially sensitive, and can pick up on transmission trouble long before it becomes apparent. 

How Are Fault Codes Diagnosed?

Car repair facilities are equipped with diagnostic tools that are plugged into a port located in your car’s interior. Your car’s system will then generate a series of fault codes, each tied to one of your car’s many systems.

The technician is then able to follow up on any fault codes with an inspection and work-up to identify and repair the issue.

If you prefer the DIY approach, you can find hand-held code readers at automotive supply stores or online. Just make sure it is compatible with your car’s vintage, make and model.

Even if you won’t be taking the DIY approach to repairing the issue, pulling the diagnostic codes will provide a good data point for discussion with your automotive tech.

In either case, don’t put off following up on your “check engine” light. It can be something as simple as a loose gas cap, or as complex as a faulty transmission.

Paying attention to your car’s warning system and addressing any problems quickly is essential to your car’s long-term reliability and longevity. If you address that dreaded indicator light sooner rather than later, you could save a bundle in costly repairs.